TPS92519-Q1 [TI]
汽车 2A 双路同步降压 LED 驱动器;型号: | TPS92519-Q1 |
厂家: | TEXAS INSTRUMENTS |
描述: | 汽车 2A 双路同步降压 LED 驱动器 驱动 驱动器 |
文件: | 总47页 (文件大小:4531K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
TPS92519-Q1
ZHCSMX7A –AUGUST 2021 –REVISED DECEMBER 2021
TPS92519-Q1 4.5V 至65V、双路、汽车类2A 同步降压LED 驱动器
TPS92519-Q1 包含高级故障保护功能:逐周期开关电
流限制、自举欠压和热关断。该器件包括一个开漏故障
输出以指示输出开路和短路情况。
1 特性
• 符合面向汽车应用的AEC-Q100 标准
– 1 级:–40°C 至125°C 的工作环境温度范围
– 器件HBM 分类等级H1C
– 器件CDM 分类等级C2
• 提供功能安全
TPS92519-Q1 采用 8.1mm × 11mm 热增强型 32 引脚
HTSSOP 封装,具有 2.75mm × 3.45mm 的底部外露
焊盘。
器件信息
– 可帮助进行功能安全系统设计的文档
• 4.5V 至65V 的宽输入电压范围
• 输出电流高达2A,精度为4%
• 自适应导通时间平均电流控制
• 标称开关频率
器件型号(1)
封装尺寸(标称值)
封装
TPS92519-Q1
HTSSOP
8.1mm × 11mm
(1) 如需了解所有可用封装,请参阅数据表末尾的可订购产品附
录。
– 通道1 和通道2 为385kHz 和435kHz
– 通道1 和通道2 为2MHz 和2.1MHz
• 高级调光操作
LED+
CCOMP2
1
2
32
COMP2
UDIM2
CSN2
COUT2
RCS2
31
30
CSP2
BST2
CUV2
3
– 精确模拟调光
RUV22
RUV21
PGND
PGND
– 支持外部PWM 调光输入
– 针对外部分流调光(包括LED 矩阵管理器)进
行优化
L2
4
GND
VBST
CBST2
29
28
SW2
SW2
CIN2
5V
5
6
7
VIN2
VIN2
GND
V5A
27
26
25
24
23
22
RADJ21
• 开关逐周期过流保护
• 开关过热保护
• LED 开路和短路故障监控和报告
FLT2
IADJ2
FSET
EN
CV5D
5V
Supply
8
9
V5D
RADJ11 RADJ22
CV5A
IADJ1
FLT1
2 应用
10
11
12
GND
VIN1
VIN1
RADJ12
• 汽车前照灯和自适应LED 驱动模块
21
20
VBST
SW1
SW1
CIN1
3 说明
13
GND
PGND
PGND
CBST1
L1
14
CUV1
15
19
18
RUV11
BST1
CSP1
RUV12
TPS92519-Q1 是一款单片双路同步降压 LED 驱动
器,具有4.5V 至65V 宽工作输入电压范围,可独立为
两串串联的LED 供电。
UDIM1
RCS1
CCOMP1
COUT1
16
17
COMP1
CSN1
TPS92519-Q1 实施自适应导通时间平均电流模式控制
功能,经设计可与分流 FET 调光技术和基于 LED 矩阵
管理器的动态光束前照灯兼容。自适应导通时间控制功
能可提供近乎恒定的开关频率,可使用 FSET 输入来
设置该开关频率。电感器电流感应和闭环反馈功能可在
较宽的输入电压、输出电压和环境温度范围内实现
±4% 以上的精度。
LED+
简化版原理图
高性能 LED 驱动器可使用模拟调光或 PWM 调光技术
来单独调制 LED 电流。通过在高阻抗模拟调整 (IADJ)
输入范围内将电压从 140mV 改变为 2.45V,可获得超
过 16:1 范围的线性模拟调光响应。通过使用所需占空
比和频率直接调制对应的 UDIM 输入引脚,实现 LED
电流的 PWM 调光。该器件支持高频分流 FET 调光,
并与使用LED 矩阵管理器的像素控制技术兼容。
TPS92519-Q1 支持两个或更多通道的并行运行,从而
实现驱动大电流 LED 或激光二极管所需的灵活性。电
流基于 IADJ 输入在并行通道之间共享,不受元件容差
和寄生效应的影响。
本文档旨在为方便起见,提供有关TI 产品中文版本的信息,以确认产品的概要。有关适用的官方英文版本的最新信息,请访问
www.ti.com,其内容始终优先。TI 不保证翻译的准确性和有效性。在实际设计之前,请务必参考最新版本的英文版本。
English Data Sheet: SLUSEG1
TPS92519-Q1
ZHCSMX7A –AUGUST 2021 –REVISED DECEMBER 2021
www.ti.com.cn
Table of Contents
7.4 Device Functional Modes..........................................27
8 Application and Implementation..................................28
8.1 Application Information............................................. 28
8.2 Typical Application.................................................... 32
9 Power Supply Recommendations................................37
10 Layout...........................................................................37
10.1 Layout Guidelines................................................... 37
10.2 Layout Example...................................................... 38
11 Device and Documentation Support..........................39
11.1 Documentation Support.......................................... 39
11.2 Receiving Notification of Documentation Updates..39
11.3 支持资源..................................................................39
11.4 Trademarks............................................................. 39
11.5 术语表..................................................................... 39
12 Mechanical, Packaging, and Orderable
1 特性................................................................................... 1
2 应用................................................................................... 1
3 说明................................................................................... 1
4 Revision History.............................................................. 2
5 Pin Configuration and Functions...................................3
6 Specifications.................................................................. 5
6.1 Absolute Maximum Ratings........................................ 5
6.2 ESD Ratings............................................................... 5
6.3 Recommended Operating Conditions.........................5
6.4 Thermal Information....................................................6
6.5 Electrical Characteristics.............................................6
6.6 Typical Characteristics................................................9
7 Detailed Description......................................................13
7.1 Overview...................................................................13
7.2 Functional Block Diagram.........................................14
7.3 Feature Description...................................................14
Information.................................................................... 39
4 Revision History
注:以前版本的页码可能与当前版本的页码不同
Changes from Revision * (August 2021) to Revision A (December 2021)
Page
• 将状态从“预告信息”更改为“量产数据”....................................................................................................... 1
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5 Pin Configuration and Functions
COMP2
UDIM2
PGND
PGND
VIN2
1
32
CSN2
CSP2
BST2
SW2
2
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
3
4
5
SW2
VIN2
6
FLT2
IADJ2
FSET
EN
GND
7
V5A
8
V5D
9
GND
10
11
12
13
14
15
16
IADJ1
FLT1
SW1
VIN1
VIN1
PGND
PGND
UDIM1
COMP1
SW1
BST1
CSP1
CSN1
图5-1. DAP Package 32-Pin HTSSOP Top View
表5-1. Pin Functions
PIN
NO.
DAP
19
I/O
DESCRIPTION
NAME
BST1
BST2
P
Supply input for high-side MOSFET gate drive circuit. Connect a ceramic capacitor
between BSTx and SWx pins. An internal diode is connected between V5D and BSTx.
30
P
COMP1
COMP2
CSN1
CSN2
CSP1
16
I/O
Output of internal transconductance error amplifier. Connect an integral compensation
network to ensure stability.
1
I/O
17
I
I
I
I
Negative input (–) of internal rail-to-rail transconductance error amplifier. Connect
directly to the negative node of the LED current sense resistor, RCS
.
32
18
Positive input (+) of internal rail-to-rail transconductance error amplifier. Connect
directly to the positive node of the LED current sense resistor, RCS
.
CSP2
31
An active high logic input enables the devices. Pull this pin low to enter low power sleep
state.
EN
24
I
FLT1
FLT2
22
27
O
O
Open-drain fault indicator. Connect to V5D with a resistor to create an active low fault
signal output.
Frequency select input. Connect to V5D to operate at nominal frequency of 440 kHz.
Connect to GND to operate at nominal frequency of 2.1 MHz.
FSET
GND
25
I
Signal ground. Return for the internal voltage reference and analog circuits. Connect to
circuit ground to complete return path.
7, 10
G
IADJ1
IADJ2
23
26
I
I
Analog adjust input. Input below 100 mV disables the channel. The analog input can be
varied between 140 mV to 2.4 V to set current reference from 10 mV to 173 mV.
Connect a 0.1-μF capacitor from pin to GND.
PGND
SW1
3, 4, 13, 14
20, 21
G
P
P
Ground returns for low-side MOSFETs
Switching output of the regulator. Internally connected to both power MOSFETs.
Connect to the power inductor.
SW2
28, 29
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表5-1. Pin Functions (continued)
PIN
NO.
DAP
15
I/O
DESCRIPTION
NAME
UDIM1
UDIM2
I
I
Undervoltage lockout and external PWM dimming input. Connect to VIN through a
resistor divider to implement input undervoltage protection. Diode couple external PWM
signal to enable dimming. Locally decouple to GND using a 1-nF ceramic capacitor. Do
not float.
2
Analog supply voltage. Locally decouple to GND using a 100-nF to 1-µF ceramic
capacitor located close to the controller.
V5A
V5D
8
9
P
P
Digital supply voltage. Locally decouple to GND using a 2.2-µF to 4.7-µF ceramic
capacitor located close to the controller.
VIN1
VIN2
11, 12
5, 6
P
P
Power inputs and connections to high-side MOSFET drain node. Connect to the power
supply and bypass capacitors CIN. The path from the VIN pin to high frequency bypass
CIN and PGND must be as short as possible.
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6 Specifications
6.1 Absolute Maximum Ratings
Over operating free-air temperature range (unless otherwise noted)(1)
MIN
–0.3
–0.3
–0.3
–0.5
–3.5
–0.3
MAX
5.5
5.5
70
UNIT
V
Supply Voltage
Boot voltage
V5A, V5D to GND
BSTx to SWx
V
BSTx to PGND
V
SWx to PGND
65
V
Switch node voltage
Drain node voltage
Current
SWx to PGND (< 10ns)
VINx to PGND
V
65
1.5
430
0.5
65
V
CSNx to VINx (< 10µs)
GND to CSPx, GND to CSNx (< 10µs)
CSNx - VINx
A
mA
V
CSPx, CSNx to GND
CSPx to CSNx
V
–0.5
–0.3
–0.3
–0.3
–0.3
0.3
65
V
Inputs
UDIMx to GND
V
COMPx, IADJx, FSET, EN to GND
FLTx to GND
5.5
5.5
150
260
150
V
Outputs
V
Junction temperature
Lead temperature
Storage temperature
TJ
°C
°C
°C
Soldering, 10 s
Tstg
–65
(1) Stresses beyond those listed under Absolute Maximum Rating may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under
Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device
reliability.
6.2 ESD Ratings
VALUE UNIT
Human body model (HBM), per AEC Q100-002(1)
±2000
±750
±500
V(ESD) Electrostatic discharge
Corner pins (1, 16, 17, and 32)
Other pins
V
Charged device model (CDM), per
AEC Q100-011
(1) AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification.
6.3 Recommended Operating Conditions
Over operating free-air temperature range (unless otherwise noted)
MIN
4.5
4.5
20
NOM
MAX
63
UNIT
V
VIN
Input voltage
V5A, V5D
dV5x/dt
Bias supply
5
5.3
V
Bias supply slew-rate
V/s
∆V(CSP-
CSN)
Sensed inductor current ripple
20
mV
dvCSP/dt
ILED
CSP slew-rate
10
2
V/µs
A
LED current
fUDIM
TA
External PWM dimming frequency
Ambient temperature
Junction temperature
1000
125
150
Hz
°C
°C
–40
–40
TJ
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UNIT
6.4 Thermal Information
DEVICE
DAP (HTSSOP)
32
THERMAL METRIC(1)
RθJA
Junction-to-ambient thermal resistance(2) (3)
Junction-to-case (top) thermal resistance
Junction-to-board thermal resistance
26.2
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
RθJC(top)
RθJB
16.3
8.3
0.2
8.2
1.8
Junction-to-top characterization parameter
Junction-to-board characterization parameter
Junction-to-case (bottom) thermal resistance
ΨJT
ΨJB
RθJC(bot)
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
(2) The package thermal impedance is calculated in accordance with JESD51-7 standard with a 4-layer board and 2 W power dissipation.
(3) A heatsink or airflow would yield a much better RθJA
.
6.5 Electrical Characteristics
-40°C ≤TJ ≤150°C, V5D = V5A = 5 V, VIN = 24 V, VUDIMx = 5 V, CV5D =CV5A = 4.7 µF CBSTx = 0.1 µF, CCOMPx = 1 nF, RCSx
100 mΩ, no load on SWx, FLTx pin floating (unless otherwise noted)
=
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
EXTERNAL ANALOG AND GATE DRIVE SUPPLIES (V5D, V5A)
Rising
4.10
4.00
100
4
4.26
V
VV5D,A(UVLO) V5D and V5A UVLO threshold
Falling
3.84
V
Hysteresis
mV
mA
mA
nA
µA
μA
IV5A(STBY)
IV5D(STBY)
IV5A(SLEEP)
IV5D(SLEEP)
Analog supply stand-by current
Gate drive supply stand-by current
Analog supply sleep state current
Gate drive supply sleep state current
VUDIM1 = VUDIM2 = 0 V
VUDIM1 = VUDIM2 = 0 V
VEN = 0 V
5.5
1.3
300
24
0.9
14
VEN = 0 V
17
IVINx(SLEEP) VIN pin sleep state current
IV5D(SW) Gate drive supply switching current
VINx = 15 V, VEN = 0 V
2
4
VV5D = 5 V, VFSET = 5 V, CH1
and CH2 switching
6
10
mA
ENABLE INPUT (EN)
Enable voltage rising threshold
1.8
V
VEN
Enable voltgae falling threshold
Enable input bias current
0.8
mV
µA
IEN
10
HIGH-SIDE FET (SWx, BOOTx)
VINx = 6 V, VBSTx = 11 V, IHSx
100 mA
=
RDSx(ON-HS) High-side MOSFET on resistance
240
2.95
184
250
465
3.30
245
300
mΩ
V
Falling, VINx = 6 V, VSWx = 0 V
2.60
115
200
VBSTx(UV)
Bootstrap UVLO threshold
Hysteresis, VINx = 6 V, VSWx = 0
V
mV
µA
IQ(xBST)
Bootstrap pin quiescent current
VBSTx = 5 V, VSWx = 0 V
LOW-SIDE FET (SWx)
RDSx(ON-LS) Low-side MOSFET on resistance
HIGH-SIDE FET CURRENT LIMIT
VINx = 6 V, ILSx = 100 mA
240
465
mΩ
IHSx(ILIM)
tHSx(LEB)
tHSx(RES)
High-side current limit threshold
VINx = 6 V
VINx = 6 V
VINx = 6 V
2.8
35
3.5
60
20
4.2
80
A
High-side current sense leading-edge
blanking period
ns
ns
Current limit response time
LOW-SIDE FET CURRENT LIMIT
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6.5 Electrical Characteristics (continued)
-40°C ≤TJ ≤150°C, V5D = V5A = 5 V, VIN = 24 V, VUDIMx = 5 V, CV5D =CV5A = 4.7 µF CBSTx = 0.1 µF, CCOMPx = 1 nF, RCSx
100 mΩ, no load on SWx, FLTx pin floating (unless otherwise noted)
=
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
ILSx(ILIM)
tLSx(LEB)
Low-side sinking current limit threshold VINx = 6 V
1.67
2.50
3.5
A
Low-side current sense leading-edge
VINx = 6 V
76
ns
blanking period
SWITCHING FREQUENCY (FSET)
Frequency set input rising threshold
1.8
V
V
VFSET
Frequency set input falling threshold
Frequency set input bias current
0.8
IFSET
10
µA
VFSET = 0 V, VIN = 50 V, VCSP
38 V
=
=
=
=
384
ns
µs
ns
µs
tON(SW1)
Channel 1 on-time
Channel 2 on-time
VFSET = 5 V, VIN = 50 V, VCSP
25 V
1.36
365
VFSET = 0 V, VIN = 50 V, VCSP
38 V
tON(SW2)
VFSET = 5 V, VIN = 50 V, VCSP
25 V
1.20
ANALOG ADJUST SETTING AND CURRENT SENSE AMPLIFIER (IADJx, CSPx, CSNx)
VIADJx(CLP)
IADJx internal limit
2.38
2.45
140
100
2.52
V
Rising, VINx = 6 V
Falling, VINx = 6 V
mV
mV
VIADJx(SD)
Shutdown threshold
VCSPx = 6 V,
VIADJx > 2.45V
167.5
83.0
29.0
6.5
173.0
88.5
34.5
12.5
178.5
94.0
40.0
18.5
mV
mV
mV
mV
VCSPx = 6 V,
VIADJx = 1.22V
V(CSPx-CSNx) Current sense threshold
VCSPx = 6 V,
VIADJx = 460mV
VCSPx = 6 V,
VIADJx = 150mV
gmx(LV)
Level shift amplifier transconductance VINx = 63 V, VCSNx = 5 V
50
1.71
1.50
µA/V
V
Rising
Output short circuit detection threshold
Falling
VCSPx(SHT)
V
ON-TIME GENERATOR
tONx(MIN)
Minimum on-time.
VINx = 4.5 V
VINx = 4.5 V
90
57
110
78
130
86
ns
ns
OFF-TIME GENERATOR
tOFFx(MIN)
Minimum off-time
PWM DIMMING and PROGRAMMABLE UVLO INPUT (DIMx)
Rising
2.45
2.35
1.22
1.02
2.52
1.27
V
V
V
V
VUDIMx(DO)
UDIM dropout detection threshold
Falling
Rising
Falling
1.95
VUDIMx(EN)
UDIM undervoltage lockout threshold
0.97
6.3
UDIM source current (UVLO
hysteresis)
IUDIMx(UVLO)
VUDIMx = 1.5 V
10
12
µA
ERROR AMPLIFIER (COMPx)
gM Transconductance
VINx = 63 V
450
45
µA/V
µA
VINx = 63 V, V(CSPx–CSNx) = 0 V,
VIADJx = 1.4 V
ICOMPx(SRC) COMPx current source capacity
ICOMPx(SINK) COMPx current sink capacity
VINx = 63 V, V(CSPx–CSNx) = 200
mV, VIADJx = 1.4 V
45
µA
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6.5 Electrical Characteristics (continued)
-40°C ≤TJ ≤150°C, V5D = V5A = 5 V, VIN = 24 V, VUDIMx = 5 V, CV5D =CV5A = 4.7 µF CBSTx = 0.1 µF, CCOMPx = 1 nF, RCSx
100 mΩ, no load on SWx, FLTx pin floating (unless otherwise noted)
=
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
MHz
mV
V
EAx(BW)
EA(VD)
EA(CM)
Bandwidth
Unity gain
3
Input differential sense range
Input common mode range
225
–225
VINx = 63 V
VUDIMx = 0 V
Rising
0
VINx –0.5
ICOMPx(LKG) COMPx leakage current
2.5
2.45
425
3.2
nA
V
VCOMPx(ST) COMPx startup threshold
Hysteresis
Rising
mV
V
3.0
COMPx over-voltage detection
VCOMPx(OV)
threshold
Hysteresis
75
mV
RCOMPx(DCH) COMPx discharge FET resistance
VCOMPx(RST) Reset voltage
230
100
Ω
Falling
mV
FAULT INDICATOR (FLT)
R(FLTx)
TOC
Fault pin pull-down resistance
Hiccup retry delay time
3
7
Ω
3.6
ms
THERMAL SHUTDOWN
TSD Thermal shutdown threshold
175
°C
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6.6 Typical Characteristics
TA = TJ = 25°C, V5D = V5A = 5 V, VIN = 24 V, VUDIMx = 5 V, CV5D = CV5A = 4.7 µF CBSTx = 0.1 µF, CCOMPx = 1 nF, RCSx = 100
mΩ, no load on SWx, FLTx pin floating (unless otherwise noted)
174.5
174
10
7.5
5
173.5
173
2.5
0
-2.5
-5
172.5
172
-7.5
-10
171.5
-40 -20
0
20
40
60
80 100 120 140 160
0.024
0.524
1.024
1.524
2.024
2.524
Temperature (°C)
VIADJ (V)
VCSN = 3 V
VCSN = 3 V
VIN = 60 V
图6-1. V(CSP–CSN) Current Sense Threshold vs Temperature
图6-2. V(CSP–CSN) Current Sense Error vs IADJ Count
24
1000
1 LED
3 LED
6 LED
9 LED
12 LED
15 LED
21
18
15
12
9
800
600
400
200
0
6
3
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
-200
Average Inductor Current (A)
0
0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7
CSN Voltage, VCSN (V)
3
L = 68 µH
VIN = 60 V
VIADJ =0 V
图6-4. Minimum Ripple Voltage vs Average Inductor Current
图6-3. CSN Source Current vs CSN Voltage
4.22
4.18
4.14
4.1
19.8
19.5
19.2
18.9
18.6
18.3
18
Rising
Falling
4.06
4.02
3.98
3.94
3.9
17.7
17.4
17.1
16.8
16.5
16.2
-40 -20
0
20
40
60
80 100 120 140 160
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
Temperature (°C)
图6-5. V5D,A POR Threshold vs Temperature
图6-6. V5D Sleep Current vs Temperature
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6.6 Typical Characteristics (continued)
TA = TJ = 25°C, V5D = V5A = 5 V, VIN = 24 V, VUDIMx = 5 V, CV5D = CV5A = 4.7 µF CBSTx = 0.1 µF, CCOMPx = 1 nF, RCSx = 100
mΩ, no load on SWx, FLTx pin floating (unless otherwise noted)
400
380
360
340
320
300
280
260
240
220
200
180
2.965
2.955
2.945
2.935
2.925
2.915
2.905
2.895
2.885
2.875
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
图6-7. High Side MOSFET On Resistance vs Temperature
图6-8. Bootstrap UVLO Threshold vs Temperature
220
215
210
205
200
195
190
185
180
175
170
165
160
155
3.8
3.7
3.6
3.5
3.4
3.3
3.2
-40 -20
0
20
40
60
80 100 120 140 160
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
Temperature (°C)
图6-9. Bootstrap UVLO Hysteresis vs Temperature
400
图6-10. High-Side Current Limit Threshold vs Temperature
3
375
350
325
300
275
250
225
200
175
150
2.8
2.6
2.4
2.2
2
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
图6-11. Low-Side MOSFET On Resistance vs Temperature
图6-12. Low-Side Sinking Current Limit Threshold vs
Temperature
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6.6 Typical Characteristics (continued)
TA = TJ = 25°C, V5D = V5A = 5 V, VIN = 24 V, VUDIMx = 5 V, CV5D = CV5A = 4.7 µF CBSTx = 0.1 µF, CCOMPx = 1 nF, RCSx = 100
mΩ, no load on SWx, FLTx pin floating (unless otherwise noted)
2.452
2.451
2.45
113
112.5
112
2.449
2.448
2.447
2.446
2.445
111.5
111
110.5
110
109.5
-40 -20
0
20
40
60
80 100 120 140 160
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
Temperature (°C)
图6-13. IADJ Internal Limit vs Temperature
图6-14. Minimum On-time vs Temperature
80
79
78
77
76
75
74
1.4
1.3
1.2
1.1
1
Rising
Falling
0.9
0.8
-40 -20
0
20
40
60
80 100 120 140 160
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
Temperature (°C)
图6-16. UDIM Undervoltage Lockout Threshold vs Temperature
图6-15. Minimum Off-time vs Temperature
2.58
2.53
2.48
2.43
2.38
2.33
2.28
3.24
3.23
3.22
3.21
3.2
Rising
Falling
3.19
3.18
3.17
3.16
-40 -20
0
20
40
60
80 100 120 140 160
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (°C)
Temperature (°C)
图6-17. UDIM Dropout Detection Threshold vs Temperature
图6-18. COMP Overvoltage Detection Threshold vs
Temperature
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6.6 Typical Characteristics (continued)
TA = TJ = 25°C, V5D = V5A = 5 V, VIN = 24 V, VUDIMx = 5 V, CV5D = CV5A = 4.7 µF CBSTx = 0.1 µF, CCOMPx = 1 nF, RCSx = 100
mΩ, no load on SWx, FLTx pin floating (unless otherwise noted)
0.975
0.95
0.925
0.9
30
27.5
25
22.5
20
0.875
0.85
0.825
0.8
17.5
15
12.5
10
3 LEDs
6 LEDs
9 LEDs
12 LEDs
7.5
5
0.775
0.75
0
200 400 600 800 1000 1200 1400 1600 1800
LED Current (mA)
2.5
0
-40 -20
VFPIN = 5 V
VIN = 60 V
0
20
40
60
80 100 120 140 160
Temperature (°C)
图6-20. Efficiency vs LED Current
图6-19. COMP Leakage Current vs Temperature
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7 Detailed Description
7.1 Overview
The TPS92519-Q1 is a dual synchronous buck LED driver with a 4.5-V to 65-V input voltage range. The device
can deliver up to 2 A of continuous current per channel and power two independent strings of one to 16 series-
connected LEDs. The device implements an adaptive on-time current regulation control technique to achieve
fast transient response. This architecture uses a comparator and a one-shot on-timer that varies inversely with
input and output voltage to maintain a near-constant frequency. With the FSET pin connected to V5D the on-time
generator ensure near constant frequency of 385 kHz for channel 1 and 440 kHz for channel 2. With the FSET
pin grounded the on-time generator is programmed to operate channel 1 at approximately 2 MHz and channel 2
at 2.15 MHz. The on-time between two channels is offset to ensure low EMI signature. The integrated low offset
rail-to-rail error amplifier enables closed-loop regulation of LED current and ensures better than 4% accuracy
over a wide input, output, and temperature range.
The LED current reference is set by forcing voltage on IADJ input and can be varied from 140 mV to 2.45 V to
achieve over a 16:1 linear analog dimming range. Pulse Width Modulation (PWM) dimming of the LED current is
achieved by modulating the duty cycle of external voltage signal at UDIMx input. The external UDIMx input acts
as an enable and directly controls the LED current. This device optimizes the inductor current response and is
capable of achieving over a 1000:1 PWM dimming ratio.
The device incorporates an enhanced programmable fault feature including the following:
• Cycle-by-cycle switch overcurrent limit
• Input undervoltage protection
• Boot undervoltage protection
• Comp overvoltage protection
• Output open circuit indication
• Output short circuit indication
In addition, Thermal Shutdown (TSD) protection is implemented to limit the junction temperature at 175°C
(typical). The open-drain fault output, FLTx, indicates the status of the LEDs and is forced low whenever an
output open or short fault is detected by the device.
Toggling the enable input, EN, low forces the device in low-power sleep state. In this state, both channels are
disabled and analog supply, V5A, is disconnected to reduce the bias current drawn by the device.
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7.2 Functional Block Diagram
V5D
BST1
VIN1
+
UVLO
por
Rising: 4.1 V
Falling: 4.0 V
Hys: 100 mV
uvlo
VBG
ch1_en
V5A
Analog Supply
Sleep Enable
Bandgap
2VBG
LEB
bstuv1
lsilim1
hsilim1
slp_o
slp_o
Control
and
Switch
Fault
Thermal
Sensor
Current
Limit
Circuit
+
œ
3 V
Logic
SW1
VIADJ1
+
IADJ1
Current
Limit
Circuit
VBG
PWM &
Dropout
Detection
pwm1
dropout1
+
+
V5D
LEB
V5A
2VBG
VIN1
PGND
On Time
Control
VIN1
10 ꢀA
ton1
UDIM1
EN
CSP1
CSN1
Valley Current
Control
2VBG
Toffmin1
slp
R
V-I Converter
VIADJ1
VCSN1
+
FSET
FLT1
+
ton1
ton2
pwm1
open1
LED Fault
Detection
short1
Logic
14R
COMP1
open1
Channel 1
short1
open2
short2
FLT2
BST2
VIN2
SW2
VIADJ2
+
IADJ2
PGND
CSP2
CSN2
COMP2
Channel 2
Input
UVLO &
PWM
pwm2
dropout2
UDIM2
7.3 Feature Description
7.3.1 Buck Converter Switching Operation
The following operating description of the TPS92519-Q1 refers to the Functional Block Diagram and the
waveforms in 图 7-1. The main control loop of the TPS92519-Q1 is based on an adaptive on-time pulse width
modulation (PWM) technique that combines a constant on-time control with an inductor valley current sense
circuit for pseudo-fixed frequency operation. This proprietary control technique enables closed-loop regulation of
LED current and fast dynamic response necessary to meet the requirements for LED pixel control and LED
matrix beam applications.
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V(CSP-CSN)
IL(PK) ìRCS
V
IN - VCSN
L
VCSN
ìRCS
L
ìRCS
VVAL
t
VSW
VIN
0
t
tON
tOFF
tSW
图7-1. Adaptive On Time Control Buck Converter Waveforms
In steady state, the high-side MOSFET is turned on at the beginning of each cycle. The on-time duration of this
MOSFET is controlled by an internal one-shot timer and the high-side MOSFET is turned off after the timer
expires. The one-shot timer duration is set by the output voltage measured at the CSP pin, VCSP, and the input
voltage measured at the VIN pin, VIN, to maintain a pseudo-fixed frequency. During the on-time interval, the
inductor current increases with a slope proportional to the voltage applied across its terminals (VIN –VCSP).
The low-side MOSFET is turned on after a fixed deadtime and the inductor current then decreases with the
constant slope proportional to the output voltage, VCSP. Inductor current measured by the external sense resistor
is compared to the valley threshold, VVAL, by an internal high-speed comparator. This MOSFET is turned off and
the one-shot timer is initiated when the sensed inductor current falls below the valley threshold voltage. The
high-side MOSFET is turned on again after a fixed deadtime.
The internal rail-to-rail error amplifier sets the valley threshold voltage and regulates the average inductor current
based on a reference set by IADJx input. A simple integral loop compensation circuit consisting of a capacitor
connected from the COMP pin to GND provides a stable and high-bandwidth response. As the inductor current
is directly sensed by an external resistor, the device operation is not sensitive to the ESR of the output
capacitors and is compatible with common multi-layered ceramic capacitors (MLCC).
7.3.2 Switching Frequency and Adaptive On-Time Control
The TPS92519-Q1 uses an adaptive on-time control scheme and does not have a dedicated on-board oscillator.
The one-shot timer is programmed by the voltage on FSET input. The on-time is calculated internally using 方程
式 1 and is inversely proportional to the measured input voltage, VIN, and proportional to the measured CSP
voltage, VCSP
.
VCSP
tON = k ì
V
IN
(1)
Constant, κ, is set by the FSET pin logic.
2.606ì10-6 for channel 1
2.285ì10-6 for channel 2
¤
Œ
k =
k =
VFSET > 1.8 V
‹
Œ
›
4.890ì10-7 for channel 1
4.676ì10-7 for channel 2
¤
Œ
VFSET < 0.8 V
‹
Œ
›
(2)
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Given the duty ratio of the buck converter is VCSP / VIN, the switching period, TSW, remains nearly constant over
all operating points. Use 方程式3 to calculate the switching period.
V
IN
TSW = tON
ì
= k
VCSP
(3)
(4)
Use 方程式4 to calculate the switching frequency.
1
fSW
=
k
7.3.3 Minimum On-Time, Off-Time, and Inductor Ripple
Buck converter operation is impacted by minimum on-time, minimum off-time, and minimum peak-to-peak
inductor ripple limitations. The converter reaches the minimum on-time when operating with high input voltage
and low-output voltage. In this control scheme, the off-time continues to increase and the switching frequency
reduces to regulate the inductor current and LED current to the desired value.
VOUT(MIN)
fSW(MIN)
=
; tON = tON(MIN)
tON(MIN) ì V
IN(MAX)
(5)
The converter reaches the minimum off-time when operating in dropout (low input voltage and high output
voltage). As the on-time and off-time are fixed, the duty cycle is constant and the buck converter operates in
open-loop mode. The inductor current and LED current are not in regulation. The converter continues to switch
unless disabled by the IADJx input.
The behavior and response of valley comparator is dependent on sensed peak-to-peak voltage ripple,
ΔV(CSP-CSN), and is a function of current sense resistor, RCS, and peak-to-peak inductor current ripple,
ΔiL(PK-PK). To ensure periodic switching, the sensed peak-to-peak ripple must exceed the minimum value. At
high (near 100%) or low (near 0%) duty cycles, the inductor current ripple is not sufficient to ensure periodic
switching. Under such operating conditions, the converter transitions from periodic switching to a burst
sequence, forcing multiple on-time and off-time cycles at a rate higher than the programmed frequency. Although
the converter cannot operate in a periodic manner, the closed-loop control continues regulating the average LED
current with a larger ripple value corresponding to higher peak-to-peak inductor ripple. TI recommends choosing
an inductor, output capacitor, and switching frequency to ensure minimum sensed peak-to-peak ripple voltage
under nominal operating condition is greater than 20 mV. The Application and Implementation section
summarizes the detailed design procedure.
7.3.4 Enable
The TPS92519-Q1 has an enable input EN for start-up and shutdown control of the output. If the enable input is
greater than 1.8 V then both channels are enabled. If the enable pin is pulled below 0.8 V, the channels are
disabled and the TPS92519-Q1 is switched to a low IQ shutdown mode. In this mode, the device draws a 2-μA
typical current from the VIN pin and 17-μA typical from V5D pin. TI does not recommend leaving EN pin
floating.
7.3.5 LED Current Regulation and Error Amplifier
The reference voltage, VIADJ, is internally scaled by a gain factor of 1/14 through a resistor network. An internal
rail-to-rail error amplifier generates an error signal proportional to the difference between the scaled reference
voltage (VIADJ / 14) and the inductor current measured by the differential voltage drop between CSP and CSN,
V(CSP-CSN). This error drives the COMP pin voltage, VCOMP, and directly controls the valley threshold of the
inductor current. Zero average DC error and closed-loop regulation is achieved by implementing an integral
compensation network consisting of a capacitor connected from the output of the error amplifier to GND. As a
good starting point, TI recommends a capacitor value between 1 nF and 10 nF between the COMP pin and
GND. The choice of compensation network must ensure a minimum of 60° of phase margin and 10 dB of gain
margin. The Application and Implementation section summarizes the detailed design procedure.
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CSPx
CSNx
Current Sense Amplifier
gM
Valley Current
Control
10k
10k
+
COMPx
VIADJx(CLP)
Division by 14
V-I Converter
+
VIADJx
0.14 V to 2.45 V
140k
图7-2. Closed-loop LED Current Regulation
LED current is dependent on the current sense resistor, RCS. Use 方程式6 to calculate the LED current.
V CSP-CSN
V
(
)
IADJ
ILED
=
=
RCS
14ìRCS
(6)
LED current accuracy is a function of the tolerance of the external sense resistor, RCS, and the variation in the
sense threshold, V(CSP-CSN), caused by internal mismatch and temperature dependency of the analog
components. The TPS92519-Q1 is capable of achieving LED current accuracy of ±4% at full scale over
common-mode range and a junction temperature range of –40°C to 150°C.
7.3.6 Start-up Sequence
The start-up circuit allows the COMP pin voltage to gradually increase, thus reducing the LED current overshoot
and current surges. The switching operation is initiated after the COMP pin voltage exceeds 2.45 V. A 450-mV
hysteresis window allows the device to operate when COMP voltage is within the expected operating range of
2.2 V to 2.7 V. Switching is disabled on detection of low COMP voltage to avoid excessive negative inductor
current.
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VIADJ
0.1
VUDIM
2.45
0
VCOMP
2.45
450 mV
t
VSW
VIN
0
t
ILED
t
图7-3. Soft-Start Sequence
The duration of soft start, tss, depends on the size of the compensation capacitor and the error amplifier source
current, ICOMP(SRC)
.
2.45ìCCOMP
ICOMP(SRC)
tSS
=
(7)
The source current, ICOMP(SRC) is a function of the transconductance, gM, of the error amplifier and error
generated between the reference and the current sensed voltage.
V
≈
’
IADJ
ICOMP(SRC) = gM ì
- V
(CSP-CSN) ÷
∆
«
14
◊
(8)
With no current flowing through the LEDs, the soft start duration depends on the choice of compensation
capacitor, CCOMP, and the reference voltage, VIADJ
.
The open drain fault indicator, FLTx, is set low when the COMP voltage deviates from the nominal range and
exceeds VCOMP(OV) threshold. This setting indicates a fault condition where the converter is operating in open-
loop and the LED current is out of regulation. The corresponding channel can be disabled by setting IADJx input
below 100 mV or controlling the UDIMx input.
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7.3.7 Analog Dimming and Forced Continuous Conduction Mode
Analog dimming is accomplished by modulating the voltage connected to IADJx input. The TPS92519-Q1
improves the linear range of analog dimming by supporting forced continuous conduction mode of operation.
With synchronous MOSFETs, the inductor current is allowed to go negative for part of the switching cycle, thus
enabling linear dimming with over 16:1 dimming range.
7.3.8 External PWM Dimming and Input Undervoltage Lockout (UVLO)
The UDIM pin is a multi-function input that features an accurate input voltage detection based on bandgap
thresholds with programmable hysteresis as shown in 图 7-4. This pin functions as the external PWM dimming
input for the LEDs and monitors VIN to detect dropout and undervoltage conditions. When the rising pin voltage
exceeds the 2.45-V threshold, 10 µA (typical) of current is driven out of the UDIM pin into the resistor divider
providing programmable hysteresis. TI recommends a bypass capacitor value of 1 nF between the UDIMx pin
and GND to improve noise immunity.
200 mV
VIN
VBG
PWM &
Dropout
Detection
PWM
Standard
PWM
+
+
Dropout
V5A
RUVx2
2VBG
10 ꢀA
DDIM
UDIM
RUVH
10 kΩ
RUVx1
CUVx
QDIM
Inverted
PWM
图7-4. External PWM Dimming
The brightness of LEDs can be varied by modulating the duty cycle of the signal directly connected to the UDIM
input. In addition, either an n-channel MOSFET or a Schottky diode can be used to couple an external PWM
signal when using UDIM input in conjunction with UVLO functionality. With an n-channel MOSFET, the
brightness is proportional to the negative duty cycle of the external PWM signal. With a Schottky diode, the
brightness is proportional to the positive duty cycle of the external PWM signal.
Dropout and input undervoltage protection is achieved by connecting the resistor divider network from VIN to
UDIM pin and UDIM pin to GND. Dropout protection is activated when UDIM pin voltage drops below
VUDIMx(DO, FALLING) threshold but is held above VUDIMx(EN) threshold. In dropout protection mode, the device
disables the error amplidier and disconnects the COMP pin to maintain charge on the compensation network.
The device continues switching, ensuring fast response with minimum LED current overshoot as the converter
recovers from dropout condition. The minimum input voltage, below which dropout protection is activated is
programmed using 方程式9.
+10ì103 ì RUVx1 + RUVx2
≈
’
÷
R
(
)
)
(
UVHx
∆
V
= VINx(DO,RISE) -IUDIMx(DO) ì RUVx2
+
INx(DO,FALL)
∆
∆
÷
÷
RUVx1
«
◊
(9)
方程式 10 shows the input voltage rising threshold. When VIN exceeds the rising threshold, the error amplifier is
enabled and COMP pin is connected to compensation network to regulate LED current.
RUVx1 + RUVx2
RUVx1
V
= VUDIMx(DO,RISE) ì
INx(DO,RISE)
(10)
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Additional hysteresis to internal 100 mV is programmed by connecting an extra resistor, RUVHx, in series with
UDIM pin. This connection allows the standard resistor divider to have smaller values, minimizing PWM delays.
Input undervoltage protection is triggered when UDIM pin voltage drops below VUDIMx(EN) threshold. The device
responds to very low VIN voltage or to the external PWM input signal by disabling the error amplifier,
disconnecting the COMP pin and tri-stating the switch node. With switching disabled, inductor current and the
LED current drop to zero and the charge on the compensation network is maintained. On rising edge of PWM or
when VIN exceeds the internal hystersis of 200 mV, the converter resumes switching operation ramping inductor
current to the previous steady-state value.
方程式11 defines the VIN UVLO rising threshold.
RUVx1 + RUVx2
RUVx1
V
= VUDIMx(EN,RISE) ì
INx(UVLO,RISE)
(11)
Use 方程式12 to determine the VIN UVLO falling threshold.
+10ì103 ì RUVx1 +RUVx2
≈
’
÷
R
(
)
)
(
UVHx
≈
∆
«
’
÷
◊
RUVx1 +RUVx2
RUVx1
∆
V
= VUDIMx(EN,FALL)
ì
-IUDIMx(DO) ì RUVx2
+
INx(UVLO,FALL)
∆
∆
÷
÷
RUVx1
«
◊
(12)
7.3.9 Shunt FET Dimming or Matrix Beam Application
VCSN
VLED12
VLED1
t
V(CSP-CSN)
VVAL
0
t
图7-5. Shunt FET Dimming Transient Response
The TPS92519-Q1 is compatible with shunt FET dimming and LED Matrix Manager devices. The fast dynamic
response and adaptive on-time control topology ensure near ideal current source behavior with minimum
inductor current overshoot or undershoot. In contrast to constant off-time control, the control loop is able to
maintain LED current regulation under shorted output condition. The off-time of the converter naturally adapts to
the inductor slope and valley command while keeping the average LED current constant. 图 7-5 shows the
shunt-FET dimming transient with all LEDs switched from on to off.
The device behavior is impacted by the falling slew-rate of CSN node, VCSN. A large slew-rate in conjunction
with the parasitic capacitances from CSP and CSN to GND results in differential voltage forcing the converter to
burst with minimum on-time and minimum off-time. To avoid switch node bursting TI recommends a maximum
slew-rate (dv/dt) of 15 V/µs.
7.3.10 Bias Supply
The device is powered by an external 5-V supply connected to V5D and V5A pins. Operation is enabled when
V5D and V5A exceed the 4.1-V (typical) rising threshold and is disabled when either V5D or V5A drops below
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the 4-V (typical) falling threshold. The comparator provides 100 mV of hysteresis to avoid chatter during
transitions. The V5D supply powers the internal digital logic and the high-side and low-side gate driver circuits.
The V5A supply powers sensitive analog circuits. The two bias pins can be connected together on the PCB or
through a series 10-Ω resistor between V5D and V5A with 5-V external supply connected directly to the V5D
pin. TI recommends a capacitor from each pin to GND . The recommended range for the bypass capacitor from
V5D pin to ground is between 1 µF and 4.7 µF. The recommended range from the V5A pin to ground is between
100 nF and 1 µF. The bypass capacitor from V5D to GND must be 10 times larger than the bootstrap capacitor,
CBST, to support proper operation during PWM dimming. The voltage on V5D and V5A must never exceed 5.5 V.
In device sleep state, the V5A input is internally disconnected to reduce power consumption.
7.3.11 Bootstrap Supply
The TPS92519-Q1 contains both high-side and low-side N-channel MOSFETs. The high-side gate driver works
in conjunction with an internal bootstrap diode and an external bootstrap capacitor, CBST. During the on-time of
the low-side MOSFET, the SW pin voltage is approximately 0 V and CBST is charged from the V5D supply
through the internal diode. TI recommends a 0.1-µF to 1-µF capacitor connected with short traces between the
BST and SW pins. A larger capacitor is required to prevent a bootstrap undervoltage fault when operating at low
PWM dimming frequencies.
7.3.12 Faults and Diagnostics
表7-1 summarizes the device behavior under fault conditions.
表7-1. Fault Description
FAULT
DETECTION
DESCRIPTION
Each channel is protected by an individual thermal sensor located close to the
switching MOSFETs. The thermal protection is activated in the event the maximum
MOSFET temperature exceeds the typical value of 175°C. The corresponding channel
is forced into shutdown mode. This feature is designed to prevent overheating and
damage to the internal switching MOSFETs.
Thermal protection
TJ > 175°C
V5D(RISE) < 4.1 V
V5D(FALL) > 4 V
V5A(RISE) < 4.1 V
V5D undervoltage
lockout
The device enters the Undervoltage Lockout (UVLO). The switching operation is
disabled, the COMP capacitor is discharged.
In sleep mode, the internal V5A node is disconnected to reduce the current
consumption. The switching operation is disabled and the COMP capacitor is
discharged.
V5A undervoltage
lockout
V5A(FALL) > 4 V
The device disables error amplifier and disconnects the compensation network for the
corresponding channel. Error amplifier is enabled and compensation network is
internally connected when the input voltage rises above the dropout rising threshold,
VINx dropout
protection
VUDIMx < 2.35 V
VINx(DO,RISE)
The device disables switching operation for the corresponding channel. Switching is
enabled when the input voltage rises above the turn-on threshold, VINx(UVLO,RISE)
.
VINx undervoltage
lockout
VUDIMx < 1.02 V
.
VBSTx(RISE) > 3.14 V
VBSTx(FALL) < 2.95 V
The device turns off the high-side MOSFET and turns on the low-side MOSFET for the
corresponding channel. Normal switching operation is resumed after the bootstrap
voltage exceeds 3.14 V.
BSTx undervoltage
lockout
COMPx
overvoltage
The FLTx flag is set low to indicate that the COMP voltage exceeded the normal
operating range. This condition indicates output open circuit fault.
VCOMPx > 3.2 V
VCSNx < 2.45 V
The FLTx flag is set low to indicate an output short circuit condition based on sensed
CSNx voltage.
Short CHx output
The device turns off the high-side MOSFET and discharges the COMP capacitor when
the drain current exceeds 3.5-A typical. The low-side switch is turned on to discharge
the inductor and output capacitor. The device attempts to restart after delay of 3.6 ms
High-side switch
current limit
IHS > 3.5 A
ILS > 2.5 A
The device turns off both high-side and low-side MOSFETs and discharges the COMP
capacitor when the drain current exceeds 2.5 A typical. The device attempts to restart
after delay of 3.6 ms.
Low-side switch
current limit
The TPS92519-Q1 triggers an auto-restart on detection of the thermal shutdown, high-side, or low-side current
limit faults. In the case of thermal shutdown fault, the restart is initiated after the MOSFET temperature
decreases by the fixed hysteresis of 10°C. A soft-start sequence is initiated and switching operation is enabled.
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For a high-side or low-side current limit fault, a fixed 3.6-ms timer is initiated on detection of the fault. A restart is
initiated by the expiration of the fault timer and switching operation is enabled.
The output open circuit and short circuit faults force the FLTx pin low when biased through an external resistor
and connected to a 5-V supply. The FLTx output can be used in conjunction with a microcontroller or system
basis chip (SBC) as an interrupt and can be used to aid in fault diagnostics.
表7-2. Faults and Diagnostic Summary
FAULT OR
DIAGNOSTIC
ENABLE FAULT
TIMER
LIST
DESCRIPTION
FLT INDICATION
Thermal protection
VIN supply dropout protection
VIN supply undervoltage lockout
BST supply undervoltage lockout
COMP overvoltage
Fault
Diagnostics
Fault
No
No
No
No
No
No
Yes
Yes
No
No
No
No
No
Yes
Yes
No
No
No
VINx(DO)
VINx(UVLO)
CHxBSTUV
CHxCOMPOV
CHxSHORT
CHxHSILIM
CHxLSILIM
V5AUV
Fault
Diagnostics
Diagnostics
Fault
Short circuit detected
High-side current limit
Low-side current limit
Fault
V5A undervoltage
Diagnostics
7.3.13 Output Short Circuit Fault
The TPS92519-Q1 monitors the CSNx voltage to detect output short circuit faults. A short failure is indicated
when the CSNx voltage drops below 1.5 V. The corresponding is FLTx flag is set low. The device continues to
regulate current and operate without interruption in case of short circuit.
CSNx
CSPx
VINx
LPAR
RCS
LED+
SWx
tSH
COUT
LPAR
PGNDx
LEDÅ
图7-6. Cable Harness Parasitic Inductance
The voltage transient imposed on CSPx and CSNx inputs during short circuit is dependent on the output
capacitance and is influenced by the cable harness impedance. The inductance associated with a long cable
harness resonates with the charge stored on the output capacitor and forces CSPx and CSNx voltage to ring
below ground. The negative voltage and current are dependent on the parasitic cable harness inductance and
resistance.
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VCSN
VLED
0
tSH
t
图7-7. Short Circuit Fault Transient Behavior
When using a long cable harness, TI recommends a diode to clamp the negative voltage across CSPx and
CSNx input, as shown in 图 7-8. TI recommends a low forward voltage Schottky diode or a fast recovery silicon
diode with reverse blocking voltage rating greater than the maximum output voltage. The diode is required to be
placed close to the output capacitor and must ensure that the current flowing through CSP and CSN nodes
under negative transient condition is below the absolute maximum rating of the device.
VINx
LED+
SWx
COUT
DRP
PGNDx
LEDÅ
图7-8. CSP and CSN Transient Protection Using an External Diode
7.3.14 Output Open Circuit Fault
An LED open circuit fault ultimately causes the output voltage to increase and settle close to the input voltage.
When this occurs, the TPS92519-Q1 switching operation is then controlled by the fixed on-time and minimum
off-time resulting in a duty cycle close to 100%. Under this condition, COMP voltage exceeds VCOMPx(OV)
threshold forcing FLTx flag low.
The dynamic behavior of the device and buck converter is influenced by the input voltage, VIN, and the output
capacitor, COUT, value. The device response to open circuit can be categorized into the following three distinct
cases.
Case 1: For a Buck converter design with a small output capacitor, the switching operation in open load
condition excites the inductor and the output capacitor resonance, forcing the output voltage to oscillate. The
frequency and amplitude of the oscillation are based on the resonant frequency and Q-factor of the tank.
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VCSN
VIN
t
VCOMP
tOC
VCOMPx(OV)
t
图7-9. Open Circuit Condition With Output Voltage Oscillation
Case 2: For a buck converter design with larger output capacitor, the inductor Q-factor and resonant frequency
are much lower than the switching frequency. In this case, output voltage rises to input voltage and the converter
continues to switch with minimum off-time.
VCSN
VIN
t
图7-10. Open Circuit Condition With Minimum Off-time Operation
7.3.15 Parallel Operation
The adaptive on-time control technique enables parallel operation of two or more channels with independent
current sharing and regulation. Each channel operates independently and delivers current based on the
corresponding IADJx set point. To equally share current amongst channels, the IADJx for all channels must be
connected to the external reference voltage.
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VIADJ
IADJx
COMPx
CSNx
CSPx
SWx
CCOMPx
CHx
VEN
EN
ILED
PWM
UDIMx
Lx
RCSx
COUTx
COMPy
EN
CSNy
CSPy
SWy
CCOMPy
CHy
UDIMy
IADJy
Ly
RCSy
COUTy
VIADJ
图7-11. Parallel Channel Configuration
Startup requires all channels to be enabled simultaneously by synchronizing the rising edge of IADJx voltage
above VIADJx(SD) rising threshold. This simultaneous enabling ensures that the soft-start ramp is synchronized
and current sharing is achieved after COMP voltage increases above the rising startup threshold, VCOMPx(ST)
.
PWM dimming is achieved by connecting the external PWM signal to UDIMx pin of all parallel channels. All
parallel channels have to be controlled by single PWM dimming reference. TI does not recommend to PWM dim
individual parallel channels.
Additional considerations are necessary to account for bootstrap capacitor tolerance and the impact of the
capacitor variation when PWM dimming multiple parallel channels. Ensure that bootstrap capacitor voltage is
above the undervoltage threshold, VBSTx(UV) for all operating conditions. For application requiring very low PWM
duty cycle or low PWM dimming frequency, TI recommends to connect the COMPx pin of all parallel channels
using nonparallel diodes, as shown in 图 7-12. This connection allows the parallel channels to respond and
recovery from bootstrap undervoltage fault when operating at low PWM dimming duty cycles.
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VIADJ
IADJx
COMPx
CSNx
CSPx
SWx
CCOMPx
CHx
ILED
D
Lx
RCSx
COUTx
COMPy
CSNy
CSPy
SWy
CCOMPy
CHy
Ly
RCSy
COUTy
VIADJ
IADJy
图7-12. Parallel Channel Configuration for PWM Dimming Operation
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7.4 Device Functional Modes
The device has three functional modes: Power On Reset (POR) state, run mode and sleep mode.
7.4.1 Power On Reset (POR)
The device is in POR state when V5A or V5D input is below the undervoltage lockout threshold. In POR, both
channels are turned off. The device exits POR and enters functional modes when the V5D supply exceeds 4.1 V
(typical).
7.4.2 Run Mode
The device advances to run mode EN input is set high. In this mode, all the necessary conditions for initiating the
soft-start sequence are checked. If a fault occurs in this state, the device attempts to resume operation after
waiting for the fault timer to timeout.
Transition to sleep mode is by pulling EN input low. This action causes the device to enter a low-power state.
7.4.3 Sleep Mode
In sleep mode, the following occurs:
1. The internal regulators are disconnected from the V5A pin.
2. The oscillator is disabled.
3. The channels are disabled.
4. The high side and low side MOSFETs are turned off.
In sleep mode, the output voltage rises above 3 V as all internal loads are switched off and the leakage current
associated with high-side gate drive is forced through the switch node, SWx.
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8 Application and Implementation
备注
以下应用部分中的信息不属于TI 器件规格的范围,TI 不担保其准确性和完整性。TI 的客 户应负责确定
器件是否适用于其应用。客户应验证并测试其设计,以确保系统功能。
8.1 Application Information
图8-1 shows a schematic of a typical application for the TPS92519-Q1.
LED+
CCOMP2
1
2
32
COMP2
UDIM2
CSN2
COUT2
RCS2
31
30
CSP2
BST2
CUV2
3
RUV22
RUV21
PGND
PGND
L2
4
GND
VBST
CBST2
29
28
SW2
SW2
CIN2
5V
5
6
7
VIN2
VIN2
GND
V5A
27
26
25
24
23
22
RADJ21
FLT2
IADJ2
FSET
EN
CV5D
5V
Supply
8
9
V5D
RADJ11 RADJ22
CV5A
IADJ1
FLT1
10
11
12
GND
VIN1
VIN1
RADJ12
21
20
VBST
SW1
SW1
CIN1
13
GND
PGND
PGND
CBST1
L1
14
CUV1
15
19
18
RUV11
BST1
CSP1
RUV12
UDIM1
RCS1
CCOMP1
COUT1
16
17
COMP1
CSN1
LED+
图8-1. Buck LED Driver
8.1.1 Duty Cycle Consideration
The switch duty cycle, D, defines the converter operation and is a function of the input and output voltages. In
steady state, the duty cycle is defined using 方程式13:
VCSN
D =
V
IN
(13)
There is no limitation for small duty cycles, because at low duty cycles, the switching frequency is reduced as
needed to always ensure current regulation. The maximum duty cycle attainable is limited by the minimum off-
time duration and is a function of switching frequency.
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8.1.2 Switching Frequency Selection
Nominal switching frequency (tON > tON(MIN)) is set by input voltage, VIN, output voltage, VCSP and the FSET pin.
The switching varies slightly over operating range and temperature based on converter efficiency. 表 8-1 shows
the nominal switching frequency for channel 1 and channel 2 based on FSET pin setting.
表8-1. Frequency Setting
FSET
CHANNEL
Channel 1
Channel 2
Channel 1
Channel 2
FREQUENCY
384 kHz
VFSET > 1.8 V
438 kHz
2.04 MHz
2.14 MHz
VFSET < 0.8 V
8.1.3 LED Current Set Point
The LED current is set by the external resistor, RCS, and the IADJx pin. The current sense resistor, RCS, is
selected to meet the maximum LED current specification and 90% of the full-scale range of IADJx clamp voltage.
0.9ì V
IADJx(CLP)
RCS
=
14ìILEDx(MAX)
(14)
The LED current can be varied between minimum and maximum specified limits by modulating the voltage on
IADJx pin.
8.1.4 Inductor Selection
The inductor is sized to meet the ripple specification at 50% duty cycle. TI recommends a minimum of 30%
peak-to-peak inductor ripple to ensure periodic switching operation. Use 方程式 15 to calculate the inductor
value.
V
IN(TYP)
L =
4ì DiL ì fSW
(15)
Use 方程式 16 and 方程式 17 to calculate the RMS and peak currents through the inductor. Make sure that the
inductor is rated to handle these currents.
2
≈
∆
’
÷
DiL(MAX)
2
iL(RMS)
=
ILED(MAX) +
∆
«
÷
◊
12
(16)
(17)
DiL(MAX)
iL(PK) = ILED(MAX)
+
2
8.1.5 Output Capacitor Selection
The output capacitor value depends on the total series resistance of the LED string, rD, and the switching
frequency, fSW. 方程式18 calculates the capacitance required for the target LED ripple current.
DiL(MAX)
COUT
=
8ì fSW ìrD ì DiLED
(18)
For applications where the converter supports pixel beam or matrix LED loads, additional design considerations
influence the selection of output capacitor. The size of the output capacitor depends on the slew-rate control of
the LED bypass switches and must be carefully selected while considering the overshoot current created by the
dv/dt of the bypass switch.
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When choosing the output capacitors, it is important to consider the ESR and ESL characteristics because they
directly impact the LED current ripple. Ceramic capacitors are the best choice due to the following:
• Low ESR
• High ripple current rating
• Long lifetime
• Good temperature performance
With ceramic capacitor technology, it is important to consider the derating factors associated with higher
temperature and DC bias operating conditions. TI recommends an X7R dielectric with a voltage rating greater
than maximum LED stack voltage.
8.1.6 Input Capacitor Selection
The input capacitor buffers the input voltage for transient events and decouples the converter from the supply. TI
recommends a 2.2-µF input capacitor across the VIN pin and PGND placed close to the device, and connected
using wide traces. X7R-rated ceramic capacitors are the best choice due to the low ESR, high ripple current
rating, and good temperature performance. Additional capacitance can be required to further limit the input
voltage deviation during PWM dimming operation.
8.1.7 Bootstrap Capacitor Selection
The bootstrap capacitor biases the high-side gate driver during the high-side FET on-time. The required
capacitance depends on the PWM dimming frequency, PWMFREQ, and is sized to avoid boot undervoltage and
fault during PWM dimming operation. 方程式19 calculates the bootstrap capacitance, CBST
.
IQ(BST)
CBST
=
V
+ VBST(HYS) - VBST(UV) ìPWM
5D
FREQ
(19)
表8-2 summarizes the TI recommended bootstrap capacitor value for different PWM dimming frequencies.
表8-2. Bootstrap Capacitor Value
PWM DIMMING FREQUENCY (Hz)
BOOTSTRAP CAPACITOR (µF)
1507
1318
1055
879
0.1
0.15
0.22
0.22
0.33
0.47
1
659
439
215
108
2
8.1.8 Compensation Capacitor Selection
A simple integral compensator is recommended to achieve stable operation across the wide operating range.
The bode plot of the loop gain with different compensation capacitors is shown in 图 8-2. The buck converter
behaves as a single pole system with additional phase lag caused by the switching behavior. The gain and
phase margin is then determined by the choice of the switching frequency and is independent of other design
parameters. TI recommends a 1-nF to 10-nF capacitor to achieve bandwidth between 4 kHz and 40 kHz. The
choice of compensation capacitor impacts the transient response, the shunt FET dimming behavior and PWM
dimming performance. A larger compensation capacitor (lower bandwidth) is recommended to limit the LED
current overshoot on the rising edge of internal or external PWM signal. A smaller compensation capacitor
(higher bandwidth) is recommend to improve shunt FET dimming response.
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60
100
2.2 nF
1 nF
40
20
75
3.3 nF
4.7 nF
6.8 nF
50
10 nF
25
0
-20
-40
-60
-80
-100
0
-25
-50
-75
-100
-125
-120
1000
2000 3000 5000
10000
20000
50000 100000 200000
Frequency (Hz)
500000 1000000 2000000
5000000 1E+7
L = 68 µH, fSW = 438 kHz
图8-2. Simulated Bode Plot of Loop Gain
8.1.9 Input Undervoltage Protection
图 8-1 shows that the undervoltage protection threshold is programmed using a resistor divider, RUV1 and RUV2
,
from the input voltage, VIN, to ground. Use 方程式20 and 方程式21 to calculate the resistor values.
2ì V
V
INx(DO,FALL)
INx(UVLO,RISE)
RUVx2
=
-
-10ì103
IUDIMx(HYS)
IUDIMx(HYS)
(20)
(21)
VUDIMx(EN,RISE)
INx(UVLO,RISE) - VUDIM(EN,RISE)
RUVx1
=
ìRUVx2
V
8.1.10 CSN Protection Diode
An external Schottky diode is selected to protect the CSP / CSN node by clamping the negative voltage during
short circuit transient. The Schottky diode must be selected based on the length of the cable harness and the
choice of output capacitor. TI recommends a Schottky diode with low forward voltage drop at room-temperature
and non-repetitive peak surge current rating of 10 A for duration of 5 µs. The diode must be located close to the
CSN pin.
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8.2 Typical Application
图8-3. Application Schematic
8.2.1 Design Requirements
表8-3. Design Parameters
PARAMETER
CONDITIONS
MIN
TYP
60
MAX
UNIT
V
VIN
Input Voltage
58
62
VIN(DO)
NS
VFLED
rD
VOUT
ILED
Dropout protection threshold
Number of LEDs
Falling
55
V
1
16
3.4
LED forward voltage drop
LED string series resistance
Output voltage
2.8
0.1
2.8
100
3
V
N × rD(LED)
Ns × VFLED
1.6
Ω
V
54.4
1600
LED current
mA
Defined as percentage peak-to-peak at maximum
LED current. 5 % of maximum LED current.
LED current ripple
80
mA
ΔiLED
Defined as percentage peak-to-peak at maximum
LED current
Inductor current ripple
Start input voltage
30
28.5
5
%
V
ΔiL
VIN(UVLO,RISE)
VIN(UVLO,HYS)
Input voltage rising
Input voltage undervoltage lockout
hysteresis
V
fPWM
DPWM
VSW
TA
PWM frequency
439
Hz
%
PWM dimming duty cycle
Switching frequency
Ambient temperature
4
100
438
25
kHz
°C
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8.2.2 Detailed Design Procedure
8.2.2.1 Calculating Duty Cycle
Solve for duty cycle D, DMAX, and DMIN
:
VOUT(MAX)
54.4
58
DMAX
=
=
= 0.938
V
IN(MIN)
(22)
(23)
VOUT(MIN)
2.8
DMIN
=
=
= 0.0452
V
62
IN(MAX)
8.2.2.2 Calculating Minimum On-Time and Off-Time
Solve for minimum on-time, tON(DMIN) at minimum duty cycle and maximum on-time, tON(DMAX) at maximum duty
cycle:
VOUT(MIN)
1
2.8
62
1
tON(DMIN)
=
ì
=
ì
= 103.1ì10-9
= 2.141ì10-6
438ì103
V
fSW
IN(MAX)
(24)
(25)
VOUT(MAX)
1
54.4
58
1
tON(DMAX)
=
ì
=
ì
438ì103
V
fSW
IN(MIN)
8.2.2.3 Minimum Switching Frequency
Confirm minimum switching frequency at tON(DMIN), fSW(MIN)
:
VOUT(MIN)
2.8
103.1ì10-9 ì 62
fSW(MIN)
=
=
= 438ì103
tON(DMIN) ì V
IN(MAX)
(26)
(27)
(28)
For the design specification, tON(DMIN) > tON(MIN) and fSW(MIN) = fSW
.
8.2.2.4 LED Current Set Point
Solve for sense resistor, RCS
:
0.9ì V
0.9ì 2.45
14ì1.6
IADJ(CLP)
RCS
=
=
= 0.0984
14ìILED(MAX)
A standard resistor of 100 mΩwith tolerance better than 1 % and low temperature coefficient is selected.
8.2.2.5 Inductor Selection
The inductor is selected to meet the recommended 30% peak-to-peak inductor ripple specification:
V
V
IN(TYP)
60
4ì0.3ì1.6ì 438x103
IN(TYP)
L =
=
=
= 71.3ì10-6
4ì DiL ì fSW 4ì 0.3ìILED(MAX) ì fSW
The closest standard capacitor is 68 µH.
• Lower inductor values increase the peak-to-peak inductor current, which minimizes size and cost at the
expense of reduced efficiency and larger output capacitor.
• Higher inductance values decrease the peak-to-peak inductor current, which increases efficiency but reduces
the operating range based on minimum sense voltage ripple, ΔV(CSP-CSN) specification.
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8.2.2.6 Output Capacitor Selection
The minimum output capacitance is selected to meet the LED current ripple specification:
DiL(MAX)
0.48
8ì 438ì103 ì1.6 ì80 ì10-3
COUT
=
=
= 1.07ì10-6
8ì fSW ìrD(MAX) ì DiLED(MAX)
(29)
A standard 1-µF, 100-V X7R capacitor is selected.
8.2.2.7 Bootstrap Capacitor Selection
Referring to 表8-2, a standard 470-nF, 16-V X7R capacitor is selected to support PWM frequency of 439 Hz.
8.2.2.8 Compensation Capacitor Selection
A compensation capacitor of 2.2 nF is selected to achieve balanced transient response between PWM dimming
and shunt FET dimming.
60
100
2.2 nF
1 nF
3.3 nF
4.7 nF
6.8 nF
10 nF
40
75
20
50
0
25
-20
-40
-60
-80
-100
-120
0
-25
-50
-75
-100
-125
1000
2000 3000 5000
10000
20000
50000 100000 200000
Frequency (Hz)
500000 1000000 2000000
5000000 1E+7
图8-4. Simulated Buck Converter Bode Plot
8.2.2.9 PWM Dimming and Input Voltage Protection
The device channel enable function and external PWM signal is achieved by controlling UDIM input. The device
modulates the LED current based on the PWM duty cycle of the external signal.
Input undervoltage lockout function is implemented by selecting RUV1 and RUV2 resistor along with internal
hysteresis.
2ì V
V
IN(DO,FALL)
2ì28.5
55
IN(UVLO,RISE)
RUV2
=
-
-10ì103 =
-
-10ì103 = 190ì103
10ì10-6 10ì10-6
IUDIM(DO)
IUDIM(DO)
(30)
(31)
A standard 191-kΩresistor is selected for RUV2
.
VUDIM(EN,RISE)
1.22
28.5 -1.22
RUV1
=
ìRUV2
=
ì191ì103 = 8.54ì103
VIN(UVLO,RISE) - VUDIM(EN,RISE)
A standard 8.45-kΩresistor is selected for RUV1
.
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8.2.3 Application Curves
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch3: Inductor current (200 mA/div); Time: 1 µs/div
Ch1: SW voltage (10 V/div); Ch3: Inductor current (200 mA/
div); Ch4: COMP voltage (400 mV/div); Time: 50 µs/div
图8-6. Normal Operation
图8-5. Start-up Transient
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch3: Inductor current (200 mA/div); Ch4: LED current (200
mA/div); Time: 500 µs/div
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch3: Inductor current (200 mA/div); Ch4: LED current (200
mA/div); Time: 5 µs/div
图8-7. PWM Dimming Transient
图8-8. PWM Dimming (Rising Edge)
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch4: LED current (200 mA/div); Time: 400 µs/div
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch3: Inductor current (200 mA/div); Ch4: LED current (200
mA/div); Time: 5 µs/div
图8-10. Shunt Dimming With Matrix Manager
图8-9. PWM Dimming (Falling Edge)
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Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch4: LED current (200 mA/div); Time: 400 µs/div
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch4: LED current (200 mA/div); Time: 50 µs/div
图8-11. Shunt Dimming (LEDs ON-OFF Transient)
图8-12. Shunt Dimming (LEDs OFF to LEDs ON)
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch4: LED current (200 mA/div); Time: 50 µs/div
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch3: Inductor current (200 mA/div); Ch4: LED current (200
mA/div); Time: 50 µs/div
图8-13. Shunt Dimming (LEDs ON to LEDs OFF)
图8-14. Output Short Circuit Fault
Ch1: SW voltage (10 V/div); Ch2: Output voltage (4 V/div);
Ch3: Inductor current (200 mA/div); Ch4: LED current (200
mA/div); Time: 40 µs/div
Ch1: SW voltage (10 V/div); Ch2:
Output voltage (4 V/div); Ch3: Inductor
current (400 mA/div); Ch4: LED current
(200 mA/div); Time: 40 µs/div
图8-15. Output Short Circuit Fault Recovery
图8-16. Output Open Circuit Fault
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9 Power Supply Recommendations
This device is designed to operate from an input voltage supply range between 4.5 V and 65 V. The input can be
a car battery or another preregulated power supply. Additional bulk capacitance or an input filter can be required
in addition to the ceramic bypass capacitors to address converter stability, noise, and EMI concerns.
10 Layout
10.1 Layout Guidelines
The performance of any switching converter depends as much on the layout of the PCB as the component
selection. The following guidelines can help you design a PCB with the best power converter performance:
• Place ceramic high-frequency bypass capacitors as close as possible to the TPS92519-Q1 VIN and PGND
pins. Grounding for both the input and output capacitors must consist of localized top side planes that
connect to the PGND pins.
• Place bypass capacitors for V5D and V5A close to the pins and ground the capacitors to device ground.
• Differentially route the CSP and CSN pins to sense resistor. Route the traces away from noisy nodes,
preferably through a layer on the other side of a shielding or ground layer.
• Use ground plane in one of the middle layers for noise shielding.
• Make VIN and ground connection as wide as possible. This action reduces any voltage drops on the input of
the converter and maximizes efficiency.
10.1.1 Compact Layout for EMI Reduction
Radiated EMI is generated by the high di/dt from pulsing currents in switching converters. The larger the area
covered by the path of a pulsing current, the more electromagnetic emission is generated. The key to minimize
radiated EMI is to identify the pulsing current path and minimize the area of the path. In buck converters, the
pulsing current path is from the VIN side of the input capacitors through the HS switch, through the LS switch,
and then returns to the ground of the input capacitor.
High-frequency ceramic bypass capacitors at the input side provide primary path for the high di/dt components of
the pulsing current. Placing ceramic capacitors as close as possible to the VIN and PGND pins is the key to EMI
reduction.
The PCB copper connection of the SW pin to the inductor must be as short as possible and just wide enough to
carry the LED current without excessive heating. Short, thick traces or, copper pours (shapes), must be used for
high current conduction path to minimize parasitic resistance. Place the output capacitor close to the CSN pin
and grounded closely to the PGND pin.
10.1.1.1 Ground Plane
TI recommends using one of the middle layers as a solid ground plane. The ground plane provides shielding for
sensitive circuits and traces. The ground plane also provides a quiet reference potential for the control circuitry.
Connect the GND and PGND pins to the ground plane using vias right next to the bypass capacitors. PGND pins
are connected to the source of the internal LS switch. The pins must be connected directly to the grounds of the
input and output capacitors. The PGND net contains noise at the switching frequency and can bounce due to
load variations.
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10.2 Layout Example
COMP2
UDIM2
PGND
PGND
VIN2
CSN2
CSP2
BST2
SW2
1
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
2
3
4
SW2
5
VIN2
FLT2
IADJ2
FSET
EN
6
GND
7
V5A
8
V5D
9
GND
IADJ1
FLT1
SW1
10
11
12
13
14
15
16
VIN1
VIN1
PGND
PGND
UDIM1
COMP1
SW1
BST1
CSP1
CSN1
图10-1. TPS92519-Q1 Layout Example
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11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation see the following:
Texas Instruments, TPS92519-Q1 Evaluation Module User's Guide
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 支持资源
TI E2E™ 支持论坛是工程师的重要参考资料,可直接从专家获得快速、经过验证的解答和设计帮助。搜索现有解
答或提出自己的问题可获得所需的快速设计帮助。
链接的内容由各个贡献者“按原样”提供。这些内容并不构成 TI 技术规范,并且不一定反映 TI 的观点;请参阅
TI 的《使用条款》。
11.4 Trademarks
TI E2E™ is a trademark of Texas Instruments.
所有商标均为其各自所有者的财产。
11.5 术语表
TI 术语表
本术语表列出并解释了术语、首字母缩略词和定义。
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
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PACKAGE OPTION ADDENDUM
www.ti.com
14-Oct-2022
PACKAGING INFORMATION
Orderable Device
Status Package Type Package Pins Package
Eco Plan
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
Samples
Drawing
Qty
(1)
(2)
(3)
(4/5)
(6)
TPS92519QDAPRQ1
ACTIVE
HTSSOP
DAP
32
2500 RoHS & Green
NIPDAU
Level-3-260C-168 HR
125 to -40
92519Q
Samples
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Dec-2021
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
B0
K0
P1
W
Pin1
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant
(mm) W1 (mm)
TPS92519QDAPRQ1 HTSSOP
DAP
32
2500
330.0
24.4
8.8
11.8
1.8
12.0
24.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Dec-2021
*All dimensions are nominal
Device
Package Type Package Drawing Pins
HTSSOP DAP 32
SPQ
Length (mm) Width (mm) Height (mm)
367.0 367.0 45.0
TPS92519QDAPRQ1
2500
Pack Materials-Page 2
GENERIC PACKAGE VIEW
DAP 32
8.1 x 11, 0.65 mm pitch
PowerPADTM TSSOP - 1.2 mm max height
PLASTIC SMALL OUTLINE
This image is a representation of the package family, actual package may vary.
Refer to the product data sheet for package details.
4225303/A
www.ti.com
PACKAGE OUTLINE
TM
DAP0032F
PowerPAD TSSOP - 1.2 mm max height
S
C
A
L
E
1
.
5
0
0
PLASTIC SMALL OUTLINE
8.3
7.9
TYP
A
PIN 1 ID AREA
30X 0.65
32
1
11.1
10.9
NOTE 3
2X
9.75
16
B
17
0.30
32X
0.19
6.2
6.0
0.1 C
0.1
C A B
SEATING PLANE
(0.15) TYP
C
SEE DETAIL A
4.11
3.29
EXPOSED
THERMAL PAD
0.25
4.06
3.16
1.2 MAX
GAGE PLANE
0.75
0.50
0.15
0.05
2X (0.9)
NOTE 5
0 - 8
2X (0.15)
NOTE 5
DETAIL A
TYPICAL
4226056/A 07/2020
PowerPAD is a trademark of Texas Instruments.
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm per side.
4. Reference JEDEC registration MO-153.
5. Features may differ and may not be present.
www.ti.com
EXAMPLE BOARD LAYOUT
TM
DAP0032F
PowerPAD TSSOP - 1.2 mm max height
PLASTIC SMALL OUTLINE
(5.2)
NOTE 9
SOLDER MASK
DEFINED PAD
(4.11)
32X (1.5)
SYMM
SEE DETAILS
1
32
32X (0.45)
30X (0.65)
(11)
NOTE 9
SYMM
(4.06)
(1.2 TYP)
(R0.05) TYP
(
0.2) TYP
VIA
16
17
(0.65) TYP
(1.3) TYP
(7.5)
METAL COVERED
BY SOLDER MASK
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:8X
METAL UNDER
SOLDER MASK
SOLDER MASK
METAL
SOLDER MASK
OPENING
OPENING
EXPOSED METAL
EXPOSED METAL
0.05 MIN
ALL AROUND
0.05 MAX
ALL AROUND
SOLDER MASK
DEFINED
NON SOLDER MASK
DEFINED
SOLDER MASK DETAILS
NOT TO SCALE
4226056/A 07/2020
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
8. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
numbers SLMA002 (www.ti.com/lit/slma002) and SLMA004 (www.ti.com/lit/slma004).
9. Size of metal pad may vary due to creepage requirement.
www.ti.com
EXAMPLE STENCIL DESIGN
TM
DAP0032F
PowerPAD TSSOP - 1.2 mm max height
PLASTIC SMALL OUTLINE
(4.11)
BASED ON
0.125 THICK
STENCIL
32X (1.5)
1
32
32X (0.45)
30X (0.65)
(4.06)
BASED ON
SYMM
0.125 THICK
STENCIL
SEE TABLE FOR
DIFFERENT OPENINGS
FOR OTHER STENCIL
THICKNESSES
17
16
METAL COVERED
BY SOLDER MASK
SYMM
(7.5)
SOLDER PASTE EXAMPLE
EXPOSED PAD
100% PRINTED SOLDER COVERAGE BY AREA
SCALE:8X
STENCIL
THICKNESS
SOLDER STENCIL
OPENING
0.1
4.60 X 4.54
4.11 X 4.06 (SHOWN)
3.75 X 3.71
0.125
0.15
0.175
3.47 X 3.43
4226056/A 07/2020
NOTES: (continued)
10. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
11. Board assembly site may have different recommendations for stencil design.
www.ti.com
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