LM3492MH/NOPB [TI]
具有升压转换器和快速电流调节器的 2 通道独立可调光 LED 驱动器 | PWP | 20 | -40 to 125;
| 型号： | LM3492MH/NOPB |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | 具有升压转换器和快速电流调节器的 2 通道独立可调光 LED 驱动器 | PWP | 20 | -40 to 125 升压转换器 驱动 光电二极管 接口集成电路 驱动器 调节器 |
| 文件： | 总32页 (文件大小：1539K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
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LM3492, LM3492-Q1
SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
LM3492/-Q1 Two-Channel Individual Dimmable LED Driver With Boost Converter and Fast
Current Regulator
1
1 Features
•
Boost Converter:
2 Applications
–
LM3492-Q1 is an Automotive Grade Product
That is AEC Q100 Grade 1 Qualified
•
Ultra-High Contrast Ratio 6.5”-10” LCD Display
Backlight up to 28 LEDs
–
Very Wide Input Voltage Ranged
From 4.5 V to 65 V
•
Automotive or Marine GPS Displays
3 Description
–
–
–
Programmable Soft Start
The LM3492/-Q1 integrates a boost converter and a
two-channel current regulator to implement a high
efficient and cost effective LED driver for driving two
individually dimmable LED strings with a maximum
power of 15 W and an output voltage of up to 65 V.
The boost converter employs a proprietary Projected-
On-Time control method to give a fast transient
response with no compensation required, and a
nearly constant switching frequency programmable
from 200 kHz to 1 MHz. The application circuit is
stable with ceramic capacitors and produces no
audible noise on dimming. The programmable peak
current limit and soft-start features reduce current
surges at start-up, and an integrated 190 mΩ, 3.9-A
N-Channel MOSFET switch minimizes the solution
size.
No Loop Compensation Required
Stable With Ceramic and Other Low ESR
Capacitors With No Audible Noise
–
Nearly Constant Switching Frequency
Programmable From 200 kHz to 1 MHz
•
Current Regulators:
–
Programmable LED Current from 50 mA to
200 mA
–
1000:1 Contrast Ratio at a Dimming
Frequency of More Than 3 kHz, Minimum LED
Current Pulse Width is 300 ns
–
–
Two Individual Dimmable LED Strings up to
65 V, Total 15 W (Typically 28 LEDs at
150 mA)
Device Information(1)
Dynamic Headroom Control Maximizes
Efficiency
PART NUMBER
LM3492
LM3492-Q1
PACKAGE
BODY SIZE (NOM)
–
–
Over-Power Protection
±3% Current Accuracy
HTSSOP (20)
7.80 mm × 4.40 mm
•
Supervisory Functions:
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
–
–
–
–
Precision Enable
COMM I/O Pin for Diagnostic and Commands
Thermal Shutdown Protection
Thermally Enhanced 20-Pin HTSSOP package
Typical Application
Copyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM3492, LM3492-Q1
SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
www.ti.com
Table of Contents
8.5 Programming........................................................... 18
Application and Implementation ........................ 20
9.1 Application Information............................................ 20
9.2 Typical Application ................................................. 20
1
2
3
4
5
6
7
Features.................................................................. 1
Applications ........................................................... 1
Description ............................................................. 1
Revision History..................................................... 2
Description (continued)......................................... 3
Pin Configuration and Functions......................... 4
Specifications......................................................... 5
7.1 Absolute Maximum Ratings ...................................... 5
7.2 ESD Ratings.............................................................. 5
7.3 Recommended Operating Conditions....................... 5
7.4 Thermal Information.................................................. 5
7.5 Electrical Characteristics........................................... 6
7.6 Typical Characteristics.............................................. 8
Detailed Description ............................................ 11
8.1 Overview ................................................................. 11
8.2 Functional Block Diagram ....................................... 12
8.3 Feature Description................................................. 12
8.4 Device Functional Modes........................................ 18
9
10 Power Supply Recommendations ..................... 23
11 Layout................................................................... 23
11.1 Layout Guidelines ................................................. 23
11.2 Layout Example .................................................... 23
12 Device and Documentation Support ................. 24
12.1 Documentation Support ........................................ 24
12.2 Related Links ........................................................ 24
12.3 Receiving Notification of Documentation Updates 24
12.4 Community Resources.......................................... 24
12.5 Trademarks........................................................... 24
12.6 Electrostatic Discharge Caution............................ 24
12.7 Glossary................................................................ 24
8
13 Mechanical, Packaging, and Orderable
Information ........................................................... 25
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision C (May 2013) to Revision D
Page
•
Added Added ESD Ratings table, Thermal Information table, Feature Description section, Device Functional Modes,
Application and Implementation section, Power Supply Recommendations section, Layout section, Device and
Documentation Support section, and Mechanical, Packaging, and Orderable Information section....................................... 1
•
Changed RθJA value from 32.7 to 36.5 in the Thermal Information table ............................................................................... 5
Changes from Revision B (May 2013) to Revision C
Page
•
Changed layout of National Data Sheet to TI format ........................................................................................................... 20
2
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SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
5 Description (continued)
The fast slew rate current regulator allows high frequency and narrow pulse width dimming signals to achieve a
very high contrast ratio of 1000:1 at a dimming frequency of more than 3 kHz. The LED current is programmable
from 50 mA to 200 mA by a single resistor.
To maximize the efficiency, Dynamic Headroom Control (DHC) automatically adjusts the output voltage to a
minimum. DHC also facilitates a single BOM for different number of LED in a string, which is required for
backlight panels of different size, thereby reducing overall development time and cost. The LM3492/-Q1 comes
with a versatile COMM pin which serves as a bidirectional I/O pin interfacing with an external MCU for the
following functions: power-good, overtemperature, IOUT overvoltage and undervoltage indications, switching
frequency tuning, and channel 1 disabling. Other supervisory functions of the LM3492/-Q1 include precise
enable, VCC undervoltage lockout, current regulator over-power protection, and thermal shutdown protection.
The LM3492/-Q1 is available in the thermally enhanced 20-pin HTSSOP package.
Copyright © 2010–2016, Texas Instruments Incorporated
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6 Pin Configuration and Functions
PWP PowerPAD™ Package
20-Pin HTSSOP
Top View
Pin Functions
PIN
I/O
DESCRIPTION
Enable
APPLICATION INFORMATION
NO.
NAME
Internally pullup. Connect to a voltage higher than 1.63 V to provide precision enable
for the device.
1
EN
I
I
2
3
4
5
6
VIN
Input Supply Voltage
Switch Node
Supply pin to the device. Input range is 4.5 V to 65 V.
SW
I
Internally connected to the drain of the integrated MOSFET.
VOUT
RT
I
I
Output Voltage Sense
Frequency Control
Sense the output voltage for nearly constant switching frequency control.
An external resistor from the VOUT pin to this pin sets the switching frequency.
Output Voltage
Feedback
The output voltage is connected to this pin through a feedback resistor divider for
output voltage regulation. The voltage of this pin is from 1.05 V to 2.5 V.
7
8
9
FB
I
G
I
GND
IOUT2
Analog Ground
Signal ground
Current Regulator Input Input of the current regulator of channel 2. The regulated current is programmable
of Channel 2 (refer to the IREF pin).
Current Regulator Input Input of the current regulator of channel 1. The regulated current is programmable
10
11
12
13
14
15
16
IOUT1
CDHC
I
I
of Channel 1
(refer to the IREF pin).
An external capacitor connected to this pin sets the DHC sensitivity. At start-up, a
120-µA internal current source charges an external capacitor to provide a soft-start
function.
Dynamic Headroom
Control
Current Setting of the
Current Regulator
An external resistor connected from this pin to ground programs the regulated current
of the current regulator of channels 1 and 2.
IREF
I
This pin is open drain for various indications (power-good, overtemperature, IOUT
overvoltage and undervoltage) and command sending (switching frequency tuning
and channel 1 disabling).
Bidirectional Logic
Communication
COMM
LGND
I/O
G
I/O
Ground of the Current
Regulator
Current regulator ground. Must be connected to the GND pin for normal operation.
The LGND and GND pins are not internally connected.
Control the ON/OFF of the current regulator of channel 1. This pin is internally pulled
low by a 5-µA current. This pin also serves as a clock signal for latching input/output
data of the COMM pin.
Dimming Control of
Channel 1
DIM1/CLK
Dimming Control of
Channel 2
Control the ON/OFF of the current regulator of channel 2. This pin is internally pulled
low by a 5-µA current.
DIM2
PGND
VCC
I
17
18
Integrated MOSFET ground. Must be connected to the GND pin for normal operation.
The PGND and GND pins are not internally connected.
G
O
Power Ground
Nominally regulated to 5.5 V. Connect a capacitor of larger than 0.47 µF between the
VCC and GND pins.
19
LDO Regulator Output
Peak Current Limit
Adjust
Connect an external resistor from the ILIM pin to the VCC pin reduces peak current
limit. Connect the ILIM pin to the ground to obtain the maximum current limit.
20
ILIM
DAP
I
DAP
—
Exposed Pad
Thermal connection pad. Connect to a ground plane.
4
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SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
7 Specifications
7.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)(1)
MIN
−0.3
−0.3
MAX
UNIT
VIN, RT, VOUT to GND
67
Input voltage
SW to GND
67
V
SW to GND (Transient)
ILIM to GND
−2 (<100 ns)
−0.3
−0.3
–0.3
150
0.3
5
Output voltage
FB to GND
V
COMM, DIM1, DIM2, to GND
6
Junction temperature, TJ
Storage temperature, Tstg
150
150
°C
°C
−65
(1) Stresses beyond those listed under Absolute Maximum Ratings 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.
7.2 ESD Ratings
VALUE
±2000
±750
UNIT
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)
Charged-device model (CDM), per JEDEC specification JESD22-C101(2)
V(ESD)
Electrostatic discharge
V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
7.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
MAX
65
UNIT
V
Supply voltage, VIN
4.5
Operation temperature, TA
–40
125
°C
7.4 Thermal Information
LM3492, LM3492-Q1
THERMAL METRIC(1)
PWP (HTSSOP)
UNIT
20 PINS
36.5
20.8
17.5
0.5
RθJA
Junction-to-ambient thermal resistance
Junction-to-case (top) thermal resistance
Junction-to-board thermal resistance
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
RθJC(top)
RθJB
ψJT
Junction-to-top characterization parameter
Junction-to-board characterization parameter
Junction-to-case (bottom) thermal resistance
ψJB
17.4
2
RθJC(bot)
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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7.5 Electrical Characteristics
over operating free-air temperature range, VIN = 12 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
START-UP REGULATOR (VCC PIN)
CVCC = 0.47 µF, no load
IVCC = 2 mA
4.7
4.7
5.5
5.5
6.3
6.3
V
V
VVCC
Output voltage
VCC pin undervoltage lockout
threshold (UVLO)
VCC_UVLO
VVCC increasing, TA = TJ = 25°C
3.56
3.78
4
V
VCC_UVLO-HYS
IIN
VCC pin UVLO hysteresis
IIN operating current
VVCC decreasing
310
3.6
mV
mA
No switching, VFB = 0 V
5.2
95
IIN operating current, device
shutdown
IIN-SD
VEN = 0 V
30
30
µA
mA
V
(1)
IVCC
VCC pin current limit
VVCC = 0 V
18
VCC pin output voltage when
supplied by VOUT
VIN = Open, IVCC = 1 mA,
VOUT = 18 V, TA = TJ = 25°C
VCC-VOUT
3.5
4.1
4.7
ENABLE INPUT
VEN
EN pin input threshold
VEN rising
VEN falling
VEN = 0 V
1.55
1.63
194
2
1.71
V
VEN-HYS
EN pin threshold hysteresis
Enable pullup current at shutdown
mV
µA
IEN-SHUT
Enable pullup current during
operation
IEN-OPER
VEN = 2 V
40
µA
CURRENT REGULATOR
VIREF
IREF pin voltage
4.5 V ≤ VIN ≤ 65 V
1.231
0.16
0.38
0.81
1.256
0.225
0.48
1.281
0.29
0.58
1.17
V
V
VDHC50
VDHC100
VDHC200
IOUT = 50 mA, RIREF = 25 kΩ
IOUT = 100 mA, RIREF = 12.5 kΩ
IOUT = 200 mA, RIREF = 6.25 kΩ
VIOUT under DHC
0.99
VIOUT = VDHC50, RIREF = 25 kΩ,
TA = TJ = 25°C
47.5
46.5
97
50
50
52.5
53.5
103
104
206
208
5
IOUT50
VIOUT = VDHC50, RIREF = 25 kΩ
VIOUT = VDHC100, RIREF = 12.5 kΩ,
TA = TJ = 25°C
100
100
200
200
IOUT100
Current output under DHC
mA
VIOUT = VDHC100, RIREF = 12.5 kΩ
96
VIOUT = VDHC200, RIREF = 6.25 kΩ,
TA = TJ = 25°C
194
192
IOUT200
VIOUT = VDHC200, RIREF = 6.25 kΩ
VDIM = 0, VIOUT = 65 V, TA = TJ =
25°C
IOUTOFF
Leakage at maximum work voltage
Minimum work voltage
µA
V
IOUT = 50 mA, RIREF = 25 kΩ,
IOUT = 0.98 × IOUT50, TA = TJ = 25°C
VIOUT50-MIN
0.1
0.2
0.15
0.35
IOUT = 100 mA, RIREF = 12.5 kΩ,
VIOUT100-MIN
IOUT = 0.98 × IOUT100
,
TA = TJ = 25°C
IOUT = 200 mA, RIREF = 6.25 kΩ,
VIOUT200-MIN
IOUT = 0.98 × IOUT200
TA = TJ = 25°C
,
0.4
0.65
0.7
VDIM-HIGH
VDIM-LOW
DIM voltage HIGH
DIM voltage LOW
1.17
V
V
BOOST CONVERTER
ICDHC-SRC CDHC pin source current
ICDHC-SINK CDHC pin sink current
VCDHC = 1.6 V, VFB = 3 V,
VIOUT = 0 V, DIM = High
60
56
µA
µA
VCDHC = 1.6 V, VFB = 3 V,
VIOUT = 3 V, DIM = High
(1) The VCC pin provides self bias for the internal gate drive and control circuits. Device thermal limitations limit external loading.
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SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
Electrical Characteristics (continued)
over operating free-air temperature range, VIN = 12 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DIM = Low, VCDHC = 2.6 V, TA = TJ
= 25°C
ICDHC-LEAKAGE
ICL-MAX
CDHC pin leakage current
5
46
nA
Integrated MOSFET peak current
limit threshold
3.3
3.9
2
4.5
A
A
Half integrated MOSFET peak
current limit threshold
ICL-HALF
RILIM = 11 kΩ
RDS(on)
VFBTH-PWRGD
IFB
Integrated MOSFET On-resistance
Power-Good FB pin threshold
Feedback pin input current
ISW = 500 mA
0.19
2.25
0.43
1
Ω
V
VFB = 3 V, TA = TJ = 25°C
µA
VIN = 12 V, VOUT = 65 V,
RRT = 300 kΩ
1460
800
550
350
VIN = 24 V, VOUT = 32.5 V,
RRT = 300 kΩ
tON
ON timer pulse width
ns
VIN = 12 V, VOUT = 65 V,
RRT = 100 kΩ
VIN = 24 V, VOUT = 32.5 V,
RRT = 100 kΩ
ON timer minimum pulse width at
current limit
tON(min)ILIM
145
145
ns
ns
tOFF
OFF timer pulse width
350
7.8
COMM PIN
COMM goes LOW during VIOUT
rising, other VIOUT = 1.2 V
VIOUT-OV
IOUT pin overvoltage threshold
5.6
6.7
V
VCOMM-LOW
ILEAK-FAULT
COMM pin at LOW
5 mA into COMM
VCOMM = 5 V
0.7
5
V
COMM pin open leakage
µA
THERMAL PROTECTION
TOTM
Overtemperature indication
TJ rising
TJ falling
TJ rising
TJ falling
135
15
°C
°C
°C
°C
Overtemperature indication
hysteresis
TOTM-HYS
TSD
Thermal shutdown temperature
165
20
Thermal shutdown temperature
hysteresis
TSD-HYS
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7.6 Typical Characteristics
Unless otherwise specified the following conditions apply: TJ = 25°C, VIN = 12 V with configuration in typical application circuit
for ILED = 200 mA shown in this data sheet.
Figure 1. Quiescent Current, IIN vs VIN
Figure 2. VCC vs IVCC
Figure 3. VCC vs VIN
Figure 4. Switching Frequency, fSW vs VIN
Figure 5. ILED Regulation vs Temperature
Figure 6. RDS(on) vs Temperature
8
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SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
Typical Characteristics (continued)
Unless otherwise specified the following conditions apply: TJ = 25°C, VIN = 12 V with configuration in typical application circuit
for ILED = 200 mA shown in this data sheet.
Figure 7. Efficiency vs VIN (ILED = 0.2 A)
Figure 8. ILED Regulation vs VIN (ILED = 0.2 A)
Figure 10. Enable Transient (ILED = 0.2 A)
Figure 9. Power Up (ILED = 0.2 A)
Figure 12. LED 50% Dimming (ILED = 0.2 A,
Dimming Frequency = 200 Hz)
Figure 11. Steady-State Operation (ILED = 0.2 A)
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Typical Characteristics (continued)
Unless otherwise specified the following conditions apply: TJ = 25°C, VIN = 12 V with configuration in typical application circuit
for ILED = 200 mA shown in this data sheet.
Figure 13. 1000:1 LED Dimming (ILED = 0.2 A,
Dimming Frequency = 200 Hz)
Figure 14. 300-ns LED Dimming Pulse Width (ILED = 0.2 A,
Dimming frequency = 3.33 kHz)
10
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SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
8 Detailed Description
8.1 Overview
The LM3492/-Q1 integrates a boost converter and a two-channel current regulator to implement a high efficient
and cost effective LED driver for driving two individually dimmable LED strings with a maximum power of 15 W
and an output voltage of up to 65 V. The boost converter provides power for the LED strings, and the current
regulator controls the dimming of the LED strings individually. The LM3492/-Q1 integrates an N-channel
MOSFET switch and a two-channel current regulator to minimize the component count and solution size.
The boost converter of the LM3492/-Q1 employs a Projected On-Time (POT) control method to determine the
on-time of the MOSFET with respect to the input and output voltages and an external resistor RRT. During the on-
period, the boost inductor is charged up, and the output capacitor is discharged to provide power to the output. A
cycle-by-cycle current limit (which is 3.9 A typically and programmable by an external resistor) is imposed on the
MOSFET for protection. After the on-period, the MOSFET is turned off such that the boost inductor is discharged.
The next on-period is started when the voltage of the FB pin is dropped below a threshold which is determined
by Dynamic Headroom Control (DHC) and is ranged from 1.05 V to 2.5 V (DHC affects the threshold only when
the DIM1 and/or DIM2 pins are high). The boost converter under POT control can maintain the switching
frequency nearly constant so that the switching frequency depends on only RRT (Figure 15). Also, POT control
requires no compensation circuit and gives a fast transient response of the output voltage.
Figure 15. Switching Frequency
The two-channel current regulator of the LM3492/-Q1 is fast response so that it can allow very high contrast ratio
(1000:1 at 3-kHz LED dimming frequency, minimum pulse width of the dimming signal is 300 ns). The two
channels are dimmable individually. Channel 1 of the current regulator can be disabled by a digital command
send through the COMM pin. In this case, the DIM1 pin can serve only as a clock signal for the data flow of the
COMM pin. The power dissipated by the current regulator is adaptively minimized by Dynamic Headroom Control
to maximize efficiency.
The LM3492/-Q1 can be applied in numerous applications like automotive LCD backlight panels. It can operate
efficiently for inputs as high as 65 V. Diagnostic functions including power good indication, overtemperature
indication, IOUT overvoltage and undervoltage indications facilitate the interface of the LM3492/-Q1 application
circuit with external microprocessors (MCUs). The LM3492/-Q1 will not latch off and continue to operate in the
presence of the indications. Other useful features include thermal shutdown, VCC undervoltage lockout, and
precision enable. The LM3492/-Q1 is available in the thermally enhanced HTSSOP package.
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8.2 Functional Block Diagram
Copyright © 2016, Texas Instruments Incorporated
8.3 Feature Description
8.3.1 Switching Frequency
The boost converter of the LM3492/-Q1 device employs a projected-on-time (POT) control method to determine
the on-time period of the MOSFET with respect to the input and output voltages and an external resistor RRT
.
During the on-time period, the boost inductor charges up, and the output capacitor discharges to provide power
to the output. A cycle-by-cycle current limit (which is 3.9 A typically and programmable by an external resistor)
protects the MOSFET. After the on-time period, the MOSFET turns off and boost inductor discharges. The next
on-time period starts when the voltage of the FB pin drops below a threshold which is determined by dynamic
headroom control (DHC) and operates from 1.05 V to 2 V. DHC affects the threshold when either the DIM1 pin is
high or the DIM2 pin is high.
During POT control operation, the boost converter maintains switching at a nearly constant frequency. During
most operating conditions, the switching frequency depends on mainly the value of RRT (Figure 16) but may see
some variation with changes in input or output voltage. Also, POT control operation requires no compensation
circuit and offers fast transient response of the output voltage. Applications that require very wide input voltage or
very wide output voltage ranges may see some variation in the switching frequency as shown in Figure 17 and
Figure 18.
12
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SNVS656D –SEPTEMBER 2010–REVISED OCTOBER 2016
Feature Description (continued)
600
560
520
480
440
400
360
320
280
240
200
950
850
750
650
550
450
350
250
150
100
200
300
400
500
600
700
800
6
8
10
12
14
16
18
20
22
24
26
RRT (kW)
Input Voltage (V)
D001
D001
ILED = 150 mA
VOUT = 30 V
VVIN = 12 V
ILED = 150 mA
VOUT = 30 V
RRT = 274 kΩ
Figure 16. Switching Frequency vs RT Resistance
Figure 17. Switching Frequency vs Input Voltage
600
570
540
510
480
450
420
390
360
330
300
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
Output Voltage (V)
D001
ILED = 150 mA
RRT = 274 kΩ
VVIN = 12 V
Figure 18. Switching Frequency vs Output Voltage
8.3.2 LDO Regulator
The LM3492/-Q1 device offers an integrated, 5.5-V, LDO regulator. For stability, connect an external capacitor
CVCC of more than 0.47-µF between the VCC and GND pins. The current limit of the LDO is typically 30 mA. The
LDO regulator can be used to pullup the open-drain COMM pin with an external resistor, and sources current to
the ILIM pin to adjust the current limit of the integrated MOSFET. When the voltage on the VCC pin (VCC) is
higher than the undervoltage lockout (UVLO) threshold of 3.78 V, the device becomes enabled and the CDHC
pin sources a current to charge up an external capacitor (CCDHC) to provide a soft-start function.
8.3.3 Enable and Disable
To enable the LM3492/-Q1 device, the voltage on the EN pin (VEN) must be higher than an enable threshold of
typically 1.63 V. If the voltage on the EN pin (VEN) is lower than 1.43 V, the device shuts down. In this case, the
LDO regulator turns off and the CDHC pin becomes internally grounded. The EN pin internally pulls up. After
enable, a 40-µA current source pulls up the EN pin. If the EN pin is connected to low such that the device is shut
down, the pullup current is reduced to 2 µA. These advantages allow the device to effectively avoid false
disabling by noise during operation, and minimize power consumption during shutdown. The enable threshold is
so precise that it can support a UVLO function for the input voltage as shown in Figure 19. The input voltage can
be connected to the EN pin through a resistor divider consisting of REN1 and REN2. This circuitry ensures that the
device operates after the input voltage reaches a minimum require value VIN(EN), as shown in Equation 1.
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Feature Description (continued)
VIN(EN) = 1.63 V(1 + REN1/ REN2
)
(1)
To maintain the VEN level below the absolute maximum specification, place a Zener diode (DEN) between the EN
pin and GND pins.
VVIN
VIN
REN1
EN
GND
REN2
DEN
Figure 19. Input Voltage UVLO Implemented by Precision Enable
After the EN pin is pulled low, the device performs the following functions:
•
•
•
resets IOUT overvoltage and undervoltage indications and the corresponding COMM bit pattern
resumes the switching frequency tuning to the normal frequency
resumes channel 1 of the current regulator if it is disabled
Pulling the EN pin low for a short period of approximately 200 ns achieves these same functions with little or no
effect on the operation of the boost converter and the current regulator.
8.3.4 Current Limit
The current limit (ICL) of the integrated MOSFET of the LM3492/-Q1 device provides a cycle-by-cycle current limit
for protection. This limit can be decreased by injecting a small signal current, IILIM into the ILIM pin. The
relationship between ICL and IILIM is described in Equation 2.
ICL = ICL(max) – 4290 × IILIM
where
•
ICL(max) is the maximum current limit (3.9 A typical)
(2)
As shown in Figure 20, create current limit functionality by connecting a resistor (RILIM) between the VCC pin and
the ILIM pin. The typical voltage on the ILIM pin is 0.7 V. To obtain the maximum current limit, connect the ILIM
pin to ground.
VCC
RILIM
CVCC
ILIM
GND
Figure 20. Programmable Current Limit
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Feature Description (continued)
8.3.5 Thermal Protection
An internal thermal shutdown circuit provides thermal protection. The circuit activates at 165°C (typically) to
disable the LM3492/-Q1 device. In this case, the LDO regulator turns off and the CDHC pin becomes internally
grounded. Thermal protection helps prevent catastrophic failures from accidental device overheating. When the
junction temperature of the device drops below 145°C (typical hysteresis = 20°C), the device resumes normal
operation.
8.3.6 Dynamic Headroom Control, Over-Ride, and Soft-Start
The LM3492/-Q1 device uses dynamic headroom control (DHC) to adjust the output voltage (VOUT) of the boost
converter to reduce the power loss of the current regulator and thereby maximize efficiency. To understand this
control function, consider VLED,n the forward voltage of an LED string connecting to the IOUTn pin and VIOUT,n as
the voltage of the IOUTn pin (where n is 1, 2 for channels 1, 2 of the current regulator). VLED,n normally and
gradually decreases (in terms of minutes) as a result of the rise of the LED die temperature during operation. The
DHC adjusts the output voltage (VOUT) by adjusting a threshold that is reflected in the voltage of the FB pin with
reference to VIOUT,n, (the difference between VOUT and VLED,n). The capacitor CCDHC sets the sensitivity of DHC,
which affects the response time on adjusting VOUT. If the capacitance value of CCDHC is small, VOUT is more
sensitive to the variation of VLED,n
.
The CCDHC capacitor acts to control the soft-start functionality. During the start-up period, the voltage of the
CDHC pin rises from 0 V to 2.25 V at a rate that depends on the value of the CCDHC capacitor. This limitation
ensures that the voltage of the FB pin (as well as the output voltage) ramps up in a controlled manner, and
effectively implements a soft-start function.
An internal switch grounds the CDHC pin during any of the following cases:
•
•
•
VVCC is below the VCC UVLO threshold
a thermal shutdown occurs
the EN pin is pulled low
The CDHC pin cannot be connected to the ground externally.
8.3.7 Current Regulator
The LM3492/-Q1 device integrates a two-channel current regulator for controlling the current of two LED strings.
The two LED strings dim individually by applying individual dimming signals to the DIM1 and DIM2 pins for LED
strings 1 and 2, which are connected from the VOUT pin to the IOUT1 and IOUT2 pins. The device pulls the
DIM1 and DIM2 pins low internally. The lowest contrast ratio is 1000:1. The finest pulse width of the dimming
signal for the DIM1 and DIM2 pins is 300 ns.
The device sets the current of an LED string (ILED) from 50 mA to 200 mA by using an external resistor RIREF
connected between the IREF pin and ground. Figure 21 describes the relationship between ILED and RIREF. The
two channels of the current regulator can work in parallel for only one LED string by connecting the IOUT1 and
IOUT2 pins together to provide an LED current of up to 400 mA. In this case, connect the DIM1 and DIM2 pins
together.
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Feature Description (continued)
Figure 21. LED Current vs Current Reference Resistance
Figure 22. Over-Power Protection
(RIREF
)
If the voltage on the IOUTn (n = 1, 2) pin is higher than 24 V when channel n is on, the regulated current of
channel n reduces linearly if the voltage further increases (as shown in Figure 22). The regulated current of
another channel is not affected. This over-power protection feature avoids damaging the current regulator owing
to the shorting of many LEDs in one string.
8.3.8 Output Voltage Feedback
The device feeds the output voltage back to the FB pin through a feedback circuit consisting of RFB1, RFB2, and
CFB as shown in Figure 23. To assist the feeback functionality, maintain a value of 10 pF for CFB. The DC
component of the output voltage feedback uses RFB1 and RFB2. The voltage of the FB pin VFB can be adjusted by
DHC. When VFB reaches VFB-OVP, the maximum output voltage of the boost converter VOUT(max) reaches its
maximum, as shown in Equation 3.
VOUT(max) = 2.5 V (1 + RFB1/ RFB2
)
(3)
During DHC operation, maintain the output voltage at a nominal voltage but not the maximum. The nominal
output voltage (VOUT(nom)) is described in Equation 4.
VOUT(nom) = max (VLED,n + VIOUT,n), n = 1, 2
where
•
•
VLED,n is the forward voltage of LED string n
VIOUT,n is the voltage of the IOUTn pin, where n is 1, 2 for channels 1, 2 of the current regulator)
(4)
The minimum value of VIOUT,n is approximately 5 Ω × ILED. The nominal voltage of the FB pin (VFB(nom)) is
recommended to be from 1.05 V to 2 V. Equation 5 describes the relation between VOUT(max), VOUT(nom), and
VFB(nom)
:
VOUT(max) = VOUT(nom) × 2.5 V / VFB(nom)
(5)
VOUT
FB
CFB
RFB1
GND
RFB2
Figure 23. Output Voltage Feedback Circuit
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Feature Description (continued)
8.3.9 Bidirectional Communication Pin
The COMM pin of the LM3492/-Q1 device is an open-drain bidirectional I/O pin for interfacing with an external
MCU for the following functions:
•
•
•
•
•
power-good indication
overtemperature indication
output current overvoltage and undervoltage indications
switching frequency tuning
channel 1 disabling
Except for the power good indication and the overtemperature alerts, all data flow through the COMM pin is
serial and is latched by the falling edge of the signal applying to the DIM1 pin, even when channel 1 of the
current regulator is disabled. If the DIM1 pin remains only low or only high, either by an external circuit or by
allowing it to open and pull low internally, data does not flow. Figure 24 and Figure 25 show timing diagrams of
reading and writing a bit from and to the device through the COMM pin.
Pull up the COMM pin by an MCU I/O pin, which has pullup capability, or an external resistor RCOMM connected
to the VCC pin. Without this capability, the voltage of the COMM pin remains at zero. The rise time of the output
signal of the COMM pin depends on the pullup power. If the rise time is long (RCOMM is too large or pullup power
from the connecting MCU I/O pin is too weak), data may be ready after a longer duration after the falling edge. In
this case, the design requires a longer delay between the falling edge latching and the (input or output) bit.
Figure 24. Read from the COMM Pin
8.3.9.1 Power-Good Indication
Figure 25. Write to the COMM Pin
Upon start-up, the COMM pin reads low. The output voltage of the boost converter of the LM3492/-Q1 device
rises until the voltage on the FB pin (VFB) reaches 2.25 V, when the COMM pin reads high to indicate power-
good. The power-good indication and the signal applied on the DIM1 pin are independent.
8.3.9.2 Overtemperature Indication
If the junction temperature of the LM3492/-Q1 device reaches 135°C, the COMM pin reads low, showing an
overtemperature indication. The external MCU considers to either turn off or reduce the brightness of the LED
strings to prevent overtemperature. The overtemperature indication and the signal applied on the DIM1 pin are
independent. The COMM pin reads high if the junction temperature falls below 120°C. The device does not latch
off and continues to operate in the presence of the overtemperature indication.
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Feature Description (continued)
8.3.9.3 Output Current Undervoltage Indication
The LM3492/-Q1 device gives an IOUTn (n = 1, 2) undervoltage indication if the voltage of the IOUTn pin when
DIMn is high is lower than its minimum required voltage which can regulate ILED, and the voltage of the CDHC
pin reaches its maximum. These conditions remain while the device applies 508 consecutive dimming signals on
the DIMn pin. This means that the current of the LED string n does not reach the regulation value. In most cases,
the IOUT undervoltage indication can be regarded as an open fault of the LED string n. A bit pattern (see
Table 1) can be read from the COMM pin. The device does not latch off and continues to operate in the
presence of the IOUT undervoltage indication.
8.3.9.4 Switching Frequency Tuning
After power good, the switching frequency (fSW) of the LM3492/-Q1 device can be tuned down 20% or 40%, or
resume normal by writing commands (refer to Table 2) to the COMM pin. This functionality helps avoid interfering
some sensitive devices, for example radios, working nearby the device. Upon reset, the switching frequency (fSW
)
of the device resumes normal by default. In the presence of an overtemperature indication or any COMM bit
pattern, no command can be written to the device.
8.4 Device Functional Modes
There are no additional functional modes for this device.
8.5 Programming
8.5.1 Output Current Overvoltage Indication
The LM3492/-Q1 device gives an IOUTn (n = 1, 2) overvoltage indication if the voltage of the IOUTn pin when
DIMn is higher than a threshold of typically 6.5 V. These conditions remain while the device applies 508
consecutive dimming signals on the DIMn pin. The IOUT overvoltage indication can be regarded as a short fault
of the LED string n except the following two cases:
•
powering up the device at a very low dimming ratio such that VOUT maintains at a maximum and DHC is not
fast enough to reduce VOUT
•
during DHC override condition, a bit pattern (see Table 1) can be read from the COMM pin
The device does not latch off and continues to operate in the presence of the IOUT overvoltage indication.
Table 1. COMM Indication Bit Patterns
CONDITION
PIN
BIT PATTERN
0001
IOUT1
IOUT2
IOUT1
IOUT2
Overvoltage
0011
0101
0111
Undervoltage
8.5.2 COMM Pin Bit Pattern
Table 1 summarizes all COMM bit patterns of output current overvoltage and undervoltage indications. An
existing COMM bit pattern is cleared if one of the following condition occurs:
•
•
•
the LM3492/-Q1 device is shut down
the LM3492/-Q1 device is disabled by pulling the EN pin low
the overtemperature indication is appearing
Apply the clock signal on both DIM1 and DIM2 pins when the COMM bit pattern is read by an external MCU.
Before reading the COMM bit pattern, pull the EN pin low for approximately 200 ns to reset the COMM bit
pattern. This situation does not affect the operation of the boost converter and the current regulator. After EN is
reset, if the IOUT overvoltage or undervoltage condition lasts for 508 consecutive clock cycles, the COMM pin
sends the COMM bit pattern for the MCU to read.
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In case of overtemperature, the device pulls the COMM pin low to give an overtemperature indication overriding
any other pattern. After the overtemperature indication disappears, the COMM bit pattern appears before the
overtemperature indication appears again.
8.5.3 Channel 1 Disable
After a power good verification, channel 1 of the current regulator can be disabled by writing a command (see
Table 2) to the COMM pin. If LED string 1 is malfunctioning, channel 1 can be disabled and the signal applied on
the DIM1 pin can serve as only a clock signal for the data flow of the COMM pin. Channel 1 is by default enabled
after reset. If the overtemperature indication or any COMM bit pattern has already presented, no command can
be written to the LM3492/-Q1 device.
Table 2. Channel Control Commands
COMMAND
fSW resume normal
BIT PATTERN
1111 0111 0111 0111
1111 0001 0001 0001
1111 0011 0011 0011
1111 0101 0101 0101
fSW tune down by 20%
fSW tune down by 40%
Channel 1 disable
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9 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
9.1 Application Information
The LM3492/-Q1 device is ideal for automotive and marine GPS display and applications that require a high
contrast ratio.
9.2 Typical Application
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Figure 26. Typical Application Schematic
9.2.1 Design Requirements
The following procedures are to design an LED driver using the LM3492/-Q1 with an input voltage ranged from 9
V to 24 V and two LED strings consists of 10 LEDs each with a forward voltage of 3.8 V for each LED when
running at 200 mA. The output power is 15.2 W. The switching frequency fSW is designed to be 300 kHz.
IL1(PEAK) = IL1 + ILR / 2
(6)
9.2.2 Detailed Design Procedure
9.2.2.1 RFB1, RFB2, and CFB
The nominal voltage of the LED string with 10 LEDs is 38 V, and the minimum voltage of the IOUTn pin (n = 1,
2) is 1 V when ILED is 200 mA. As a result, VOUT(nom) is 39 V. Design VOUT(max) to be 65 V. From Equation 5,
VFB(nom) is approximately 1.5 V, which falls in the recommended operation range from 1.05 V to 2 V. Also, design
RFB2 to be 16.2 kΩ. From Equation 3, RFB1 is calculated to be 405 kΩ, and a standard resistor value of 402 kΩ is
selected. CFB is selected to be 10 pF as recommended.
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Typical Application (continued)
9.2.2.2 L1
The main parameter affected by the inductor is the peak to peak inductor current ripple (ILR). To maintain a
continuous conduction mode (CCM) operation, ensure that the average inductor current IL1 is larger than half of
ILR. For a boost converter, IL1 equals to the input current IIN. Hence,
IIN = (VOUT(nom) × 2×ILED ) / VIN
(7)
Also,
ton = (1 – VIN/VOUT) / fSW
L1 = (VIN × ton) / 2IIN
(8)
(9)
If VIN is maximum, which is 24 V in this example, and only one LED string is turned on (because the two
channels of the device are individually dimmable), IIN is minimum. From Equation 7 to Equation 9, it can be
calculated that IIN(MIN), ton, and L1 are 0.325 A, 1.28 µs, and 47 µH. However, from Equation 7, IIN is maximum
when VIN is minimum, which is 9 V in this example, and the two LED strings are turned on together. Hence
IIN(max) is 1.73 A. Then, ILR is
ILR = (VIN x ton) / L1
(10)
From Equation 8, ton is 2.56 µs. From (9), ILR is 0.49 A. The steady-state peak inductor current IL1(PEAK) is
IL1(PEAK) = IL1 + ILR / 2
(11)
As a result, IL1(PEAK) is 1.98 A. A standard value of 47 µH is selected for L1, and its saturation current is larger
than 1.98 A.
9.2.2.3 D1
The selection of the boost diode D1 depends on two factors. The first factor is the reverse voltage, which equals
to VOUT for a boost converter. The second factor is the peak diode current at the steady state, which equals to
the peak inductor current as shown in Equation 11. In this example, a 100-V, 3-A Schottky diode is selected.
9.2.2.4 CIN and COUT
The function of the input capacitor CIN and the output capacitor COUT is to reduce the input and output voltage
ripples. Experimentation is usually necessary to determine their value. The rated DC voltage of capacitors used
should be higher than the maximum DC voltage applied. Owing to the concern of product lifetime, TI
recommends ceramic capacitors. But ceramic capacitors with high rated DC voltage and high capacitance are
rare in general. Multiple capacitors connecting in parallel can be used for CIN and COUT. In this example, two 10-
µF ceramic capacitor are used for CIN, and two 2.2-µF ceramic capacitor are used for COUT
.
9.2.2.5 CVCC
The capacitor on the VCC pin provides noise filtering and stabilizes the LDO regulator. It also prevents false
triggering of the VCC UVLO. CVCC is recommended to be a 1-µF, good quality and low ESR ceramic capacitor.
9.2.2.6 CCDHC
The capacitor at the CDHC pin not only affects the sensitivity of the DHC but also determines the soft-start time
tSS, the time for the output voltage to rise until power good. tSS is determined from the following equation:
CCDHC x 2.25V
tSS
=
120 mA
(12)
In this example, CCDHC is recommended to be a 0.47-µF good quality and low ESR ceramic capacitor.
9.2.2.7 RRT and RIREF
The resistors RRT and RIREF set the switching frequency fSW of the boost converter and the LED current ILED
respectively. From Figure 16, if fSW is 300 kHz, RRT is selected to be 442 kΩ. From Figure 21, if ILED is 200 mA,
RIREF is selected to be 6.19 kΩ.
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Typical Application (continued)
9.2.2.8 RCOMM
Because the COMM pin is open drain, a resistor RCOMM of 52.3 kΩ is used to connect the VCC and COMM pins
to act as a pullup function.
9.2.3 Application Curve
Figure 27. LED 50% Dimming, Both Channels Combined
(VIN = 12 V, ILED = 150 mA, 200 Hz)
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10 Power Supply Recommendations
Use a DC output power supply with a maximum output voltage capability greater than the maximum input voltage
for the application. The current rating of the supply should be greater than the maximum input current required by
the application.
11 Layout
11.1 Layout Guidelines
The layout of the printed-circuit board is critical to optimize the performance of the LM3492/-Q1 device
application circuit. In general, external components should be placed as close to the device and each other as
possible to make copper traces short and direct. In particular, components of the boost converter CIN, L1, D1,
COUT, and the LM3492/-Q1 device should be closed. Also, the output feedback capacitor CFB should be closed to
the output capacitor COUT. The ground plane connecting the GND, PGND, and LGND pins and the exposed pad
of the device and the ground connection of the CIN and COUT should be placed on the same copper layer.
Good heat dissipation helps optimize the performance of the device. The ground plane should be used to
connect the exposed pad of the device, which is internally connected to the device die substrate. The area of the
ground plane should be extended as much as possible on the same copper layer around the device. Using
numerous vias beneath the exposed pad to dissipate heat of the device to another copper layer is also a good
practice.
11.2 Layout Example
GND
CIN
EN
ILIM
VCC
CVCC
VIN
VIN
SW
L1
PGND
D1
SW
PGND
DIM2
LED+
+
VOUT
RRT
GND
RT
DIM1/CLK
LGND
RCOMM
CFB RFB1
COUT
FB
COMM
IREF
RFB2
GND
IOUT2
IOUT1
RIREF
-
-
LED- (2)
LED- (1)
CDHC
CCDHC
THERMAL/POWER VIA
Figure 28. Layout Recommendation
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12 Device and Documentation Support
12.1 Documentation Support
For related documentation see the following:
•
•
•
AN-1656 Design Challenges of Switching LED Drivers (SNVA253)
AN-2192 LM3492 12VAC, 7W LED Driver for AR111 Application (SNOA568)
AN-2056 LM3492 Evaluation Board Reference Design (SNVA438)
12.1.1 Related Documentation
12.2 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 3. Related Links
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
PARTS
PRODUCT FOLDER
SAMPLE & BUY
LM3492
Click here
Click here
Click here
Click here
Click here
Click here
Click here
Click here
Click here
Click here
LM3492-Q1
12.3 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.
12.4 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
12.5 Trademarks
PowerPAD, E2E are trademarks of Texas Instruments.
All other trademarks are the property of their respective owners.
12.6 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
12.7 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
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13 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
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10-Dec-2020
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)
LM3492MH/NOPB
LM3492MHX/NOPB
LM3492QMH/NOPB
LM3492QMHX/NOPB
ACTIVE
HTSSOP
HTSSOP
HTSSOP
HTSSOP
PWP
20
20
20
20
73
RoHS & Green
SN
Level-1-260C-UNLIM
Level-1-260C-UNLIM
Level-1-260C-UNLIM
Level-1-260C-UNLIM
-40 to 125
-40 to 125
-40 to 125
-40 to 125
LM3492
MH
ACTIVE
ACTIVE
ACTIVE
PWP
2500 RoHS & Green
73 RoHS & Green
2500 RoHS & Green
SN
SN
SN
LM3492
MH
PWP
LM3492
QMH
PWP
LM3492
QMH
(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
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
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.
OTHER QUALIFIED VERSIONS OF LM3492, LM3492-Q1 :
Catalog: LM3492
•
Automotive: LM3492-Q1
•
NOTE: Qualified Version Definitions:
Catalog - TI's standard catalog product
•
Automotive - Q100 devices qualified for high-reliability automotive applications targeting zero defects
•
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
9-Apr-2022
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)
LM3492MHX/NOPB
HTSSOP PWP
20
20
2500
2500
330.0
330.0
16.4
16.4
6.95
6.95
7.1
7.1
1.6
1.6
8.0
8.0
16.0
16.0
Q1
Q1
LM3492QMHX/NOPB HTSSOP PWP
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
9-Apr-2022
*All dimensions are nominal
Device
Package Type Package Drawing Pins
SPQ
Length (mm) Width (mm) Height (mm)
LM3492MHX/NOPB
LM3492QMHX/NOPB
HTSSOP
HTSSOP
PWP
PWP
20
20
2500
2500
356.0
367.0
356.0
367.0
35.0
35.0
Pack Materials-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
9-Apr-2022
TUBE
*All dimensions are nominal
Device
Package Name Package Type
Pins
SPQ
L (mm)
W (mm)
T (µm)
B (mm)
LM3492MH/NOPB
LM3492QMH/NOPB
PWP
PWP
HTSSOP
HTSSOP
20
20
73
73
495
495
8
8
2514.6
2514.6
4.06
4.06
Pack Materials-Page 3
MECHANICAL DATA
PWP0020A
MXA20A (Rev C)
www.ti.com
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