LDC0851HDSGT [TI]
适用于无 MCU 应用的差动电感开关 | DSG | 8 | -40 to 125;
| 型号： | LDC0851HDSGT |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | 适用于无 MCU 应用的差动电感开关 | DSG | 8 | -40 to 125 开关 |
| 文件： | 总40页 (文件大小：2911K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
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LDC0851
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
LDC0851 差分感应开关
1 特性
3 说明
1
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阈值容限：<1% 线圈直径
LDC0851 是一款近距离感应开关，是存在检测、事件
计数和简易按钮等 应用 的理想选择。
开关操作在整个温度范围内保持稳定
平均电源电流：10sps 时 < 20µA
关断电源电流：140nA
推挽式输出
当导电物体进入感应线圈的接近范围内时将触发开关。
该器件包含的滞后功能可保证一个可靠的开关阈值，从
而不受机械振动的影响。差分实现方案可防止因温度变
化或湿度影响等环境因素而导致误触发。
可通过电阻编程设定阈值
对直流磁场不敏感
电感式传感技术即使在有尘土、油污或潮气的环境中也
可实现可靠而准确的感应，因此非常适合严苛或脏污的
环境。固态开关消除了磁簧、机械或接触开关常会引发
的失败。与同类竞争产品不同的是，LDC0851 无需使
用磁体，而且不受直流磁场的影响。
非接触式开关操作
采样速率：高达 4ksps
电源电压：1.8V – 3.3V
工作温度范围：40°C 至 125°C
2 应用
器件信息(1)
•
打开/关闭开关
器件型号
封装
封装尺寸（标称值）
–
–
–
家庭安防和篡改检测
打印机
LDC0851
WSON-8
2mm x 2mm
(1) 要了解所有可用封装，请见数据表末尾的可订购产品附录。
个人电子产品
•
事件计数
–
–
–
–
风扇转速 RPM 检测
旋转编码器
流量计
增量旋钮/拨盘
•
•
简易按钮
–
–
工业用键盘
个人电子产品
工业用接近开关
4 简化电路原理图
LDC0851
Output High
(LS > LR)
Differential
LDC Core
LSENSE
LCOM
LREF
Inductance
Converter
LS
+
OUT
Output Low
(LS < LR)
Sensor
Cap
LR
Approaching
Metal Target
+
œ
Inductance
Converter
dswitch
œ
Sense
Coil
Reference
Coil
1.8 V
dswitch
1.8 V
Offset Adjust
4-bit ADC
VDD
EN
R1
R2
ADJ
Power
Management
CBYP
GND
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.
English Data Sheet: SNOSCZ7
LDC0851
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
www.ti.com.cn
目录
8.2 Functional Block Diagram ....................................... 10
8.3 Feature Description................................................. 11
8.4 Device Functional Modes........................................ 18
Application and Implementation ........................ 19
9.1 Application Information............................................ 19
9.2 Typical Application ................................................. 21
1
2
3
4
5
6
7
特性.......................................................................... 1
应用.......................................................................... 1
说明.......................................................................... 1
简化电路原理图........................................................ 1
修订历史记录 ........................................................... 2
Pin Configuration and Functions......................... 3
Specifications......................................................... 4
7.1 Absolute Maximum Ratings ...................................... 4
7.2 ESD Ratings ............................................................ 4
7.3 Recommended Operating Conditions....................... 4
7.4 Thermal Information.................................................. 4
7.5 Electrical Characteristics........................................... 5
7.6 Interface Voltage Levels ........................................... 5
7.7 Timing Requirements................................................ 6
7.8 Typical Characteristics.............................................. 7
Detailed Description ............................................ 10
8.1 Overview ................................................................. 10
9
10 Power Supply Recommendations ..................... 28
11 Layout................................................................... 29
11.1 Layout Guidelines ................................................. 29
11.2 Layout Example .................................................... 29
12 器件和文档支持 ..................................................... 31
12.1 器件支持................................................................ 31
12.2 社区资源................................................................ 31
12.3 商标....................................................................... 31
12.4 静电放电警告......................................................... 31
12.5 Glossary................................................................ 31
13 机械、封装和可订购信息....................................... 31
8
5 修订历史记录
Changes from Original (December 2015) to Revision A
Page
•
产品预览至量产数据版本 ........................................................................................................................................................ 1
2
Copyright © 2015–2016, Texas Instruments Incorporated
LDC0851
www.ti.com.cn
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
6 Pin Configuration and Functions
DSG Package
8-Pin WSON with DAP
Top View
LCOM
1
2
3
4
8
VDD
LSENSE
LREF
ADJ
7
6
5
GND
EN
DAP
OUT
Pin Functions
PIN
TYPE(1)
DESCRIPTION
NAME
LCOM
LSENSE
LREF
ADJ
NO.
1
2
A
A
A
A
O
I
Common coil input
Sense coil input
Reference coil input
Threshold adjust pin
Switch output
3
4
OUT
5
EN
6
Enable input
GND
VDD
7
G
P
G
Ground
8
Power Supply
DAP
DAP
Connect to Ground for improved thermal performance(2)
(1) I = Input, O = Output, P = Power, A = Analog, G = Ground
(2) There is an internal electrical connection between the exposed Die Attach Pad (DAP) and the GND pin of the device. Although the DAP
can be left floating, for best performance the DAP should be connected to the same potential as the device's GND pin. Do not use the
DAP as the primary ground for the device. The device GND pin must always be connected to ground.
Copyright © 2015–2016, Texas Instruments Incorporated
3
LDC0851
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
www.ti.com.cn
7 Specifications
7.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)
(1)
MIN
MAX
3.6
3.6
2
UNIT
V
VDD
Vi
Supply Voltage Range
Voltage on LSENSE, LREF, and EN
Voltage on ADJ and LCOM
Current LSENSE, LREF, and VOUT
Junction Temperature
-0.3
-0.3
V
V
IA
5
mA
°C
°C
TJ
-55
-65
150
150
Tstg
Storage Temperature
(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
±1000
±250
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
1.71
-40
NOM
MAX
3.46
125
UNIT
V
VDD
TA
Supply Voltage
Operating Temperature
°C
7.4 Thermal Information
over operating free-air temperature range (unless otherwise noted)
LDC0851
DSG (WSON)
8 PINS
67.4
THERMAL METRIC(1)
UNIT
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
89.3
37.3
ψJT
Junction-to-top characterization parameter
Junction-to-board characterization parameter
Junction-to-case (bottom) thermal resistance
2.4
ψJB
37.7
RθJC(bot)
9.2
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report (SPRA953).
4
Copyright © 2015–2016, Texas Instruments Incorporated
LDC0851
www.ti.com.cn
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
7.5 Electrical Characteristics(1)
Over recommended operating conditions unless otherwise noted. VDD= 3.3 V, EN tied to 3.3 V, TA=25 °C, ADJ tied to GND.
PARAMETER
TEST CONDITIONS
MIN(2)
TYP(3)
MAX(2)
UNIT
POWER
VDD
Supply Voltage
1.71
3.46
V
(4)
ISTATIC
Static Supply Current
0.70
0.66
0.14
mA
ƒSENSOR = 15 MHz
Dynamic Supply Current (not including
sensor current)(4)
IDYN
mA
µA
CPARASITIC = 22 pF
ISD
Shutdown Mode Supply Current
1
SENSOR
VDD = 1.71 V
4.35
6
mA
mA
ISENSOR_MAX
Maximum sensor current(4)
VDD = 3.3 V
CTOTAL = 33 pF
VDD = 1.71 V
2.5
1.8
19
LSENSOR_MIN
Sensor Minimum Inductance(5)
CTOTAL = 33 pF
VDD = 3.3 V
µH
Sensor inductance = 2 µH
CTOTAL = 33 pF
ƒSENSOR_MAX
Max Sensor Resonant Frequency(5)
Minimum total capacitance on LCOM(5)
MHz
CTOTAL
33
pF
Includes parasitic pin capacitance and
PCB parasitic capacitance
Pin parasitic capacitance on LCOM
12
8
pF
pF
CIN
Pin parasitic capacitance on LREF and
LSENSE
DETECTION
dHYST
Switching distance hysteresis(6)
Switching threshold tolerance(6)
2.5 %
0.1 %
dTOL
THRESHOLD ADJUST
VADJ
Adjust input range
Adjust threshold tolerance
0
VDD/2
V
VADJ_TOL
± 6
mV
(1) Electrical Characteristics Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions
result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ > TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) Limits are ensured by testing, design, or statistical analysis at 25°C. Limits over the operating temperature range are ensured through
correlations using statistical quality control (SQC) method.
(3) Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary
over time and will also depend on the application and configuration. The typical values are not tested and are not guaranteed on
shipped production material.
(4) Refer to section Active Mode for a description and calculation of the various supply currents.
(5) See Sensor Design for sensor guidance.
(6) Two matched 10 mm diameter sensors were used with a switching distance of 3 mm. See Hysteresis for more information.
7.6 Interface Voltage Levels
PARAMETER
MIN
TYP
MAX
0.2ˣVDD
0.4
UNIT
VIH
VIL
Input High Voltage
Input Low Voltage
0.8ˣVDD
V
V
V
V
VOH
VOL
Output High Voltage(1mA source current)
Output Low Voltage (1mA sink current)
VDD-0.4
Copyright © 2015–2016, Texas Instruments Incorporated
5
LDC0851
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
www.ti.com.cn
7.7 Timing Requirements
Over recommended operating conditions unless otherwise noted. VDD= 3.3 V, EN tied to 3.3 V, TA=25 °C, ADJ tied to GND.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
VOLTAGE LEVELS
tCONVERSION
tDELAY
tSTART
tAMT
Conversion time
ƒSENSOR = 15 MHz
ƒSENSOR = 15 MHz
290
580
450
450
<1
µs
µs
µs
µs
µs
Output delay time (Response time)
Start-up time
Shutdown-to-active mode transition time
Active-to-shutdown mode transition time
tSMT
VDD
tD
EN
tD
tD
tD
tD
LREF
No metal
Present
fsense = fref
Metal
Present
fsense > fref
Metal
Present
fsense > fref
LSENSE
OUT
1st Sample Output
2nd Sample Output
Power-on Start State
tCONVERSION
tCONVERSION
tCONVERSION
ttSTART
t
t(1st Sample)t
t(2nd Sample)t
t(3rd Sample)t
ttDELAY
t
Figure 1. Start-up and Delay Time Diagram
Refer to Power-Up Conditions for more information on the Power-On Start State.
VDD
t
LCOM
t
EN
t
Metal
Detected
(LOW)
1st Sample Output
Metal Detected (LOW)
1st sample in progress
OUT
Power Down State (HIGH)
(HIGH)
t
tCONVERSION
ttAMT
t
t(1st Sample)t
ttSMT
t
Figure 2. Shutdown and Resume Active Mode Timing Diagram
6
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LDC0851
www.ti.com.cn
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
7.8 Typical Characteristics
Common test conditions (unless specified otherwise): VDD = 3.3 V, Sense coil diameter = reference coil diameter, Target:
Aluminum, 1.5 mm thickness, Target area / Coil area > 100%
12
10
8
4
3.5
3
Switch ON
Switch OFF
Switch ON
Switch OFF
2.5
2
6
1.5
1
4
2
0.5
0
0
1
2
3
4
5
6
7
8
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
Target Distance to LREF Coil (mm)
ADJ Code
D001
D002
Basic Operation Mode
Coil diameter = 10 mm
ADJ Code = 0
Threshold Adjust Mode
Coil diameter = 10 mm
No reference target
图 3. Switching Distance vs. LREF Target Distance
图 4. Switching Distance vs. ADJ code
120
100
80
60
40
20
0
80
70
60
50
40
30
20
10
0
Switch ON (dcoil = 6 mm)
Switch ON (dcoil = 15 mm)
Switch ON (dcoil = 29 mm)
Switch OFF (dcoil = 6 mm)
Switch OFF (dcoil = 15 mm)
Switch OFF (dcoil = 29 mm)
Switch ON (dcoil = 6 mm)
Switch ON (dcoil = 15 mm)
Switch ON (dcoil = 29 mm)
Switch OFF (dcoil = 6 mm)
Switch OFF (dcoil = 15 mm)
Switch OFF (dcoil = 29 mm)
0
20
40
60
80
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
Target Distance to LREF Coil (% of coil diameter)
ADJ Code
D003
D004
Basic Operation Mode
ADJ Code = 0
Threshold Adjust Mode
Coil diameter = 6 mm, 15 mm, 29 mm
No reference target
Coil diameter = 6 mm, 15 mm, 29 mm
图 5. Normalized Switching Distance vs. LREF Target
图 6. Normalized Switching Distance vs. ADJ Code
Distance
240
100
90
80
70
60
50
40
30
20
10
0
dcoil = 29 mm
dcoil = 15 mm
dcoil = 6 mm
220
200
180
160
140
120
100
dcoil = 29 mm
dcoil = 15 mm
dcoil = 6 mm
0
20
40
60
80
100
0
20
40
60
80
100
Target Distance to LSENSE Coil (% of coil diameter)
Target Distance to LSENSE Coil (% of coil diameter)
D005
D006
LSENSE frequency (fs) varied
LREF frequency (fr) fixed
LSENSE inductance (Ls) varied
LREF inductance (Lr) fixed
图 7. Frequency vs. Distance
图 8. Inductance vs. Distance
版权 © 2015–2016, Texas Instruments Incorporated
7
LDC0851
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
www.ti.com.cn
Typical Characteristics (接下页)
Common test conditions (unless specified otherwise): VDD = 3.3 V, Sense coil diameter = reference coil diameter, Target:
Aluminum, 1.5 mm thickness, Target area / Coil area > 100%
20
18
16
14
12
10
8
20
18
16
14
12
10
8
CTOTAL < 33 pF
CTOTAL < 33 pF
Valid Region
Valid Region
6
6
4
4
2
2
ISENSOR > 6 mA
5
ISENSOR > 4.35 mA
5
0
0
0
10
Sensor Frequency (MHz)
15
20
0
10
Sensor Frequency (MHz)
15
20
D008
D007
ISENSOR_MAX = 6 mA
ISENSOR_MAX = 4.35 mA
Specified for closest target proximity or minimum inductance in the
application.
Specified for closest target proximity or minimum inductance in the
application.
图 10. Sensor Design Space for VDD = 3.3 V
图 9. Sensor Design Space for VDD = 1.8 V
10
1.5
2 µH
20 µH
200 µH
1.4
1.3
1.2
1
-40°C
-25°C
0°C
50°C
75°C
100°C
125°C
1.1
1
25°C
0.1
1.7
2.2
2.7
3.2
3.7
1.7
2.2
2.7
3.2
3.7
VDD (V)
VDD (V)
D009
D010
CTOTAL = 100 pF
CBOARD = 12 pF
ƒSENSOR = 30 MHz
图 11. ISENSOR vs. VDD
图 12. IDYN vs. VDD
0.7
10
-40°C
-25°C
0°C
50°C
75°C
100°C
125°C
Ç 25°C
25 - 50°C
50 - 75°C
75 - 100°C
100 - 125°C
0.65
0.6
25°C
1
0.1
0.55
0.5
0.01
0.45
0.4
0.001
1.7
2.2
2.7
3.2
3.7
1.7
2.1
2.5
2.9
3.3
3.7
VDD (V)
VDD (V)
D011
D012
图 13. ISTATIC vs. VDD
图 14. ISD vs. VDD
8
版权 © 2015–2016, Texas Instruments Incorporated
LDC0851
www.ti.com.cn
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
Typical Characteristics (接下页)
Common test conditions (unless specified otherwise): VDD = 3.3 V, Sense coil diameter = reference coil diameter, Target:
Aluminum, 1.5 mm thickness, Target area / Coil area > 100%
100
10
1
0
2 µH
5 µH
10 µH
20 µH
-2
-4
-6
-8
fSENSOR = 0.5 MHz
fSENSOR = 4 MHz
fSENSOR = 12 MHz
0.1
-10
0
5
10
15
20
1.7
2.2
2.7
3.2
3.7
Sensor Frequency (MHz)
VDD (V)
D013
D014
See 公式 4
Normalized to frequency at VDD = 3.6 V
图 16. ƒSENSOR Shift vs. VDD
图 15. ISENSOR vs. ƒSENSOR
版权 © 2015–2016, Texas Instruments Incorporated
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LDC0851
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
www.ti.com.cn
8 Detailed Description
8.1 Overview
The LDC0851 is an inductance comparator with push/pull output. It utilizes a sensing coil and a reference coil to
determine the relative inductance in a system. The push/pull output (OUT) switches low when the sense
inductance drops below the reference and returns high when the reference inductance is higher than the sense
inductance. Matching the sense and reference coils is important to maintain a consistent switching distance over
temperature and to compensate for other environmental factors. The LDC0851 features internal hysteresis to
prevent false switching due to noise or mechanical vibration at the switching threshold. The switching threshold is
set by the sensor characteristics and proximity to conductive objects, which is considered Basic Operation Mode
described further in section Basic Operation Mode. The LDC0851 also features a Threshold Adjust Mode where
an offset is subtracted from the reference inductance to change the effective switching point as described in
section Threshold Adjust Mode.
The sensing coil is connected across the LSENSE and LCOM pins and the reference coil is connected across
the LREF and LCOM pins. A sensor capacitor is connected from LCOM to GND to set the sensor oscillation
frequency. The sensor capacitor is common to both LSENSE and LREF making the inductance measurement
differential.
8.2 Functional Block Diagram
LDC0851
Differential
LDC Core
Sense
Coil
Output High
(LS > Adjusted LR)
LSENSE
LCOM
LREF
Inductance
Converter
LS
+
OUT
Sensor
Cap
Adjusted LR
+
œ
Inductance
Converter
Output Low
(LS < Adjusted LR)
œ
Reference
Coil
Switch
Mode Select
0: Basic Operation
1 œ 15: Threshold Adjust
VDD
VDD
VDD
EN
R1
R2
ADJ
Offset
Power
Management
4-bit ADC
CBYP
GND
10
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LDC0851
www.ti.com.cn
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
8.3 Feature Description
8.3.1 Basic Operation Mode
The LDC0851 is configured for Basic Operation mode when the ADJ pin is tied to ground. Two identical coils
should be used for LSENSE and LREF. The switching point occurs when the inductances of both coils are equal.
Basic Operation mode can be used for a wide variety of applications including event counting or proximity
sensing. An example showing gear tooth counting can be found in section Event Counting.
For proximity sensing the switching point can be set by placing a conductive target at a fixed distance from the
reference coil as shown in 图 17. The output will switch when a conductive target approaches LSENSE and
reaches the same distance set by the fixed reference target. For reliable and repeatable switching it is
recommended to place the reference target at a distance less than 40% of the coil diameter from the reference
coil.
Output High
(LS > LR)
LS (Inductance)
LR (Inductance)
Output Low
(LS < LR)
Target Distance
∞
0
dswitch = d
Differential
LDC Core
LDC0851
Sense
Coil
Movable
Metal Target
LSENSE
LCOM
LREF
Inductance
Converter
LS
+
OUTPUT
Sensor
Cap
LR
Fixed
Reference
+
œ
Inductance
Converter
œ
Reference
Coil
Switching distance set
by Reference Target
Mode Select
0: Basic Operation
VDD
1 œ 15: Threshold Adjust
VDD
EN
ADJ
Offset
Power
Management
4-bit ADC
CBYP
GND
图 17. Basic Operation Mode Diagram for Distance Sensing With Reference Target
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ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
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Feature Description (接下页)
In some systems adding a reference target at a fixed height to set the switching distance is not feasible.
Therefore to set the switching distance a small amount of mismatch between the sense and reference coils can
be introduced. To achieve the maximum switching distance the reference inductance should be approximately
0.4% less than the sense inductance as shown in 图 18 below. The 0.4% mismatch will ensure that the output
will switch off when the target is removed.
Output High
(LS > LR)
LR (Inductance)
LS (Inductance)
Output Low
(LS < LR)
Target Distance
∞
0
dswitch ≈ 0.8 x dcoil
Differential
LDC Core
LDC0851
Sense
Coil
Movable
Metal Target
LSENSE
LCOM
LREF
Inductance
Converter
LS
+
OUTPUT
Sensor
Cap
LR
+
œ
Inductance
Converter
œ
Reference
Coil
Switching distance set by
mismatch of Sense and
Reference Coils
Mode Select
0: Basic Operation
VDD
1 œ 15: Threshold Adjust
VDD
EN
ADJ
Offset
Power
Management
4-bit ADC
CBYP
GND
图 18. Basic Operation Mode Diagram for Distance Sensing With Mismatched Coils
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Feature Description (接下页)
8.3.2 Threshold Adjust Mode
In Threshold Adjust mode, an offset inductance is subtracted from LREF to alter the switching threshold without
the use of a reference target. In order to configure the LDC0851 for Threshold Adjust mode, place a resistor
divider between VDD and GND as shown in 图 19. The threshold adjust values can then be easily changed as
described in section Setting the Threshold Adjust Values. Threshold adjust mode can be used in a variety of
applications including coarse proximity sensing and simple button applications as shown in Coarse Position
Sensing. Two example coil configurations for proximity sensing are shown below for side by side coil orientation
in 图 19 as well as stacked configuration in 图 20.
Output High
(LS > Adjusted LR)
LSENSE
. . .
Adjusted LR
(ADJ = 1)
Adjusted LR
(ADJ = 15)
Output Low
(LS < Adjusted LR)
Target Distance
∞
0
dswitch ≈ 0.4x(dcoil
)
dswitch
(ADJ = 1)
(ADJ = 15)
. . .
Differential
LDC Core
LDC0851
Movable
Metal Target
Sense
Coil
LSENSE
LCOM
LREF
Inductance
Converter
LS
+
OUTPUT
Switching distance set
by ADJ Value
Sensor
Cap
Adjusted LR
+
œ
Inductance
Converter
No Target on
Reference
œ
Reference
Coil
Mode Select
VDD
R1
VDD
0: Basic Operation
1 œ 15: Threshold Adjust
VDD
EN
ADJ
Offset
Power
Management
4-bit ADC
CBYP
R2
GND
图 19. Threshold Adjust Mode for Distance Sensing Using Side by Side Coils
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Feature Description (接下页)
Stacked coils can be utilized in designs where PCB space is a concern or if the user only wants to detect
proximity to metal from one side of the PCB such as a button application. The sensing range is slightly reduced
due to the fact that both the sense and the reference coil are affected by same conductive target, however since
the sense coil is closer to the target its respective inductance decreases more than the reference inductance
allowing the output to switch as shown in 图 20.
Output High
(LS > Adjusted LR)
LS
. . .
Adjusted LR
(ADJ = 1)
Adjusted LR
(ADJ = 15)
Output Low
(LS < Adjusted LR)
Target Distance
∞
0
dswitch ≈ 0.3x(dcoil
)
dswitch
(ADJ = 1)
(ADJ = 15)
Differential
LDC Core
LDC0851
. . .
LSENSE
LCOM
LREF
Inductance
Converter
LS
+
Movable
Metal Target
OUTPUT
Sensor
Cap
Adjusted LR
+
Ref
Coil
Sense
Coil
œ
Inductance
Converter
œ
Switching distance set by ADJ
Value and separation between
Sense and Ref coils
Mode Select
VDD
R1
VDD
0: Basic Operation
1 œ 15: Threshold Adjust
VDD
EN
ADJ
Offset
Power
4-bit ADC
Management
CBYP
R2
GND
图 20. Threshold Adjust Mode for Distance Sensing Using Stacked Coils
To get the most sensing range with stacked coils the spacing between the sensing coil and reference coil (height
= h) should be maximized as shown in 图 21. See section Stacked Coils for more information on the layout of
stacked coils.
Layers 1, 2
Sense Coil
h
Layers 3, 4
Reference Coil
图 21. Stacked Coil Separation (PCB Side View)
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Feature Description (接下页)
8.3.3 Setting the Threshold Adjust Values
To configure a threshold setting, connect a 49.9 kΩ resistor (R1) between VDD and the ADJ pin as shown in 图
20. The threshold is determined by the value of R2 as shown in the 表 1 below. R1 and R2 should be 1% or
tighter tolerance resistors with a temperature coefficient of <50 ppm/°C.
表 1. Resistor Values for ADJ
Code
ADJ Code
R2 (kΩ)
3.32
5.11
7.15
9.31
11.5
14
1
2
3
4
5
6
7
16.5
19.6
22.6
26.1
30.1
34
8
9
10
11
12
13
14
15
39
44.2
49.9
The switching distance for each ADJ code can be approximated with the following formula:
ADJCode
16
≈
’
dswitch = dcoil ì0.4ì 1-
∆
÷
◊
«
where:
•
•
•
dswitch is the approximated switching distance threshold
dcoil is the coil diameter, in the same units as dswitch
ADJCode is the desired value from 表 1
(1)
For example, consider a coil with a diameter of 10 mm: An ADJ code of 1 will yield a switching distance of 3.75
mm and for a code of 15 a switching distance of 0.25 mm. This method helps reduce the effort needed to design
the coil ratio precisely for a specific switching distance. It should be noted that the maximum sensing distance is
determined almost entirely by the diameter of the coil for circular coils or by the minimum outer dimension for
rectangular coils.
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8.3.4 Hysteresis
The LDC0851 includes hysteresis for the switching threshold. The switch point is determined by the inductance
ratio between LSENSE and LREF. When the ratio of LSENSE to LREF drops below 99.6%, the device switches
ON (output low). When LSENSE/LREF becomes greater than 100.4% it switches OFF (output high). The
hysteresis window is therefore specified 0.8% from the switch ON point.
Output
State
VOH
VOL
LSENSE / LREF
tLHYST
t
Switch ON
Switch OFF
(LS /LR = 0.996)
(LS /LR = 1.004)
图 22. Inductance Hysteresis
For proximity sensing, hysteresis may also be approximated in terms of distance as shown in 图 23.
Output
State
tdTOL
t
VOH
VOL
Target
Distance
tdHYST
t
Switch ON
(dswitch
Switch OFF
(drelease
)
)
图 23. Switching Distance Hysteresis and Threshold Tolerance
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8.3.5 Conversion Time
The length of time for the LDC0851 to complete one conversion and update the output is called the conversion
time and is a function of sensor frequency. The conversion time is calculated with the following equation:
1
tCONVERSION
=
231.0ì10-6 ì ƒSENSOR
where:
•
•
tCONVERSION is the conversion time interval
ƒSENSOR is the sensor frequency given by 公式 6
(2)
It is important to note that the frequency of the sensor increases in the presence of conductive objects. Therefore
the worst case conversion time is calculated with no target present or when the target is at the maximum
distance from the sensor.
8.3.6 Power-Up Conditions
This indicates the switch output state when there is no metal target within the switching distance of LDC0851. On
power-up the LDC0851 output will be held HIGH until the part performs the sensor test and is ready for normal
operation. This remains true even if the enable pin (EN) is pulled low. A HIGH to LOW transition on the OUT line
occurs when the metal target comes within the switching distance of LDC0851. In the case of any sensor fault
condition the LDC0851 maintains a HIGH state. An example of a sensor fault is if the sensor gets disconnected
or damaged.
OUT
NH Type
No
Metal
No Metal/
Sensor Fault
Metal
HIGH
LOW
t
t
+ t
conversion
start
图 24. Output Status at Power up and in Presence of Metal Target
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8.4 Device Functional Modes
8.4.1 Shutdown Mode
To save power, the LDC0851 has a shutdown mode. In order to place the LDC0851 in shutdown mode set the
EN (Enable) pin low. This mode is useful for low power applications where the EN pin can be duty cycled at a
low rate for wake-up applications to achieve a very low average supply current. An example of a duty-cycled
application can be found in the applications section Low Power Operation. To resume active operation, set EN
high and wait tAMT + tDELAY for valid output data. The current consumption in this mode is given in the electrical
table as ISD. Note that the output will remain high (OFF) when EN is low. See Power-Up Conditions for more
information on the startup conditions.
8.4.2 Active Mode
When the LDC0851 EN pin is pulled high, the LDC0851 is put into active mode. The active supply current (IDD) is
broken up into three pieces: Static current (Istatic), Dynamic current (Idyn), and Sensor current (Isensor).
Static current is the DC device current given in the electrical characteristics and does not vary over frequency.
Dynamic current is the AC device current which varies with both sensor frequency (ƒSENSOR) and board parasitic
capacitance (CBOARD). Dynamic current can be computed with the following equation:
Idyn = (24.262ì10-12)ìƒSENSOR +1.5ìƒSENSOR ìCBOARD
where:
•
•
•
Idyn is the dynamic current drawn by the device and board parasitics
ƒSENSOR is the sensor frequency calculated from 公式 6
CBOARD is the parasitic capacitance of the board, see 图 25
(3)
Sensor current is the AC current required to drive an external LC sensor. Sensor current varies with both the
frequency and inductance of the sensor and is given by the following equation:
1
Isensor
=
17.1ìLSENSOR ì ƒSENSOR
where:
•
•
•
ISENSOR is current required to drive the sensor
LSENSOR is the measured inductance of the sensor
ƒSENSOR is the sensor frequency calculated from 公式 6
(4)
The total active supply current is given by the following equation:
IDD = Idyn +Istatic +Isensor
where:
•
•
•
•
IDD is the total active supply current
Idyn is the dynamic current drawn by the device as given by 公式 3
Istatic is the static current as given in the electrical table
ISENSOR is current required to drive the sensor as given by 公式 4
(5)
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9 Application and Implementation
注
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
9.1.1 Sensor Design
The LDC0851 relies on two externally placed sensors (LSENSE and LREF) and a capacitor (CSENSOR) for proper
operation. The design and matching of the coils is very critical to ensure a proper switching occurrence. It is also
important to note that the parasitic capacitance of the board (CBOARD) and of the LCOM input pin (CIN_COM) are in
parallel with CSENSOR, and the sum of all three capacitances create a total capacitance (CTOTAL) which is
considered part of the system. CTOTAL must be greater than 33 pF to be considered in the valid design space.
Board
Parasitic
Pin
Parasitic
Sensor Components
LDC0851
LSENSE
LCOM
CIN_SENSE
CBOARD
LSENSE
Inductive Switch
Core
CBOARD
CIN_COM
CSENSOR
LREF
LREF
CIN_REF
CBOARD
图 25. Sensor Components, Board Parasitics, and Package Parasitics Diagram
9.1.1.1 Sensor Frequency
The sensor frequency is calculated with the following equation.
2
ƒSENSOR
=
2pì LSENSOR ì CTOTAL
where:
•
•
•
ƒSENSOR is the calculated oscillation frequency with no target present
LSENSOR is the inductance of the sense coil or reference coil
CTOTAL is sum of external sensor, board parasitic, and pin parasitic capacitances connected to LCOM, refer to
图 25
(6)
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Application Information (接下页)
9.1.1.2 Sensor Design Procedure
The following procedure should be followed for determining the sensor characteristics:
1. Determine the diameter of coil (dcoil), which should be 3 times larger than the desired switching distance
(dswitch
)
2. Determine the desired frequency (ƒSENSOR) which should be between 300 kHz and 19 MHz
3. Calculate the range of allowable inductance from the following equation:
1
LSENSOR
í
4.83ì(ƒSENSOR )ì(ISENSOR_MAX
)
where:
•
•
LSENSOR is the inductance of the LSENSE coil or LREF coil
ISENSOR_MAX is given in the electrical table
(7)
(8)
4. Calculate the externally placed sensor capacitor:
1
CSENSOR
=
- CBOARD - CIN_COM
(pì ƒSENSOR )2(2ìLSENSOR
)
where:
•
•
CBOARD is the parasitic capacitance introduced by the board layout (~4 pF for good layout)
CIN_COM is the parasitic pin capacitance of LCOM specified as 12 pF in the electrical table
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9.2 Typical Application
9.2.1 Event Counting
The LDC0851 can be used for event counting applications such gear tooth detection or rotational speed
measurements. An example of gear tooth detection using side by side coils is shown below where the gear is
made of a conductive material and rotates over the coils. Two identical coils can be placed such that when one
of the coils is covered by a gear tooth, the other is uncovered. The output will toggle when the inductance values
of both coils are equal as the gear passes by.
Rotation (,)
LS
LR
LC
ADJ
LDC Output
LDC0851
图 26. Gear Tooth Functional Diagram
9.2.1.1 Design Requirements
Assume a gear with 8 conductive teeth is used in a system to determine flow rate. Determine the maximum
speed that can be reliably detected by the LDC0851 using a sensor frequency of 15 MHz.
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Typical Application (接下页)
9.2.1.2 Detailed Design Procedure
To ensure a reliable reading an event must be sampled twice when the gear tooth covers more of the LSENSE
coil than the LREF coil (LS<LR) producing a LOW output and equivalently twice when the gear tooth covers
more of LREF than LSENSE (LR<LS) producing a HIGH output. The maximum speed can be achieved when the
output toggles at a duty cycle rate of 50%. This can be achieved by using a gear where the width of each tooth is
the same as the width of the gaps between the teeth. For asymmetric systems, the minimum width of either the
gap or the gear tooth determines the maximum detectable speed. For symmetrical systems, the maximum
rotational speed that can be reliably detected in revolutions per minute (rpm) for a given number of gear teeth
can be determined by the following formula:
≈
∆
«
’
÷
◊
1
60
Gear Speed (rpm) = ì ƒSENSOR ì 231.0 ì10-6
ì
»
ÿ
⁄
4
# gear teeth
where:
•
•
•
Gear Speed (rpm) is the calculated speed of the gear
ƒ SENSOR is the sensor frequency given by 公式 6
# gear teeth is the total number of events per rotation
(9)
A gear with 8 teeth and sensor frequency of 15MHz could reliably measure a gear rotational speed of 6500 rpm.
9.2.1.3 Application Curves
The metal coverage has an inverse relationship to coil inductance. 图 27 shows the relationship between the
output of the LDC0851 and relative inductance of the coils as the gear is rotating.
Coil Inductance (L)
Reference coil inductance exceeds Sense coil
inductance which causes output to switch low
LDC Output
Max inductance
(Metal Coverage = 0%)
Equal Inductance
(Metal Coverage = 50%)
LR
LS
Min inductance
(Metal Coverage = 100%)
Sense coil inductance exceeds Reference coil
inductance which causes output to switch low
Rotation Angle (,)
图 27. Angular Position vs Coil Inductance
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Typical Application (接下页)
9.2.2 Coarse Position Sensing
The LDC0851 may be used for coarse proximity sensing such as a push button application. A conductive target
may be added to the underside of a mechanical push button as shown below.
图 28. Coarse Position Sensing Side View
9.2.2.1 Design Requirements
A push button that is made of flexible material has a conductive target attached to the underside and a
contactless solution using the LDC0851 is required for reliability purposes. Determine the coil characteristics as
well as the threshold adjust setting if the following conditions are true:
1. The target is made of a conductive material, such as aluminum foil or copper tape
2. The conductive target is circular and measures 10 mm in diameter
3. The resting height of the conductive target is 2.5 mm above the PCB when no button push
4. The maximum travel distance when pressed is 2 mm, leaving an airgap of 0.5mm above the PCB
9.2.2.2 Detailed Design Procedure
To conserve PCB area, a 4 layer stacked coil approach is used with the sense coil on the top 2 layers and
reference on the bottom 2 layers. The LDC0851 switching threshold is then determined by following parameters:
1. Conductive Target Size: The best response is achieved when the target area is ≥100% compared to the coil
area.
2. Coil diameter: The diameter of the coil should be at least 3x greater than the desired switching distance.
3. ADJ code: Increasing ADJ code linearly scales down the switching distance estimated by 公式 1.
The coil diameter should not exceed the diameter of the conductive target of 10mm in order to keep the target-to-
coil coverage ≥100%. Additionally, in order to detect the lightest button pushes where the conductive target rests
at a height of 2.5 mm, the coil should be at least 3 times greater giving a minimum size of 7.5 mm. The user may
therefore select a coil size between 7.5 mm and 10 mm. A coil diameter of 10mm is chosen for the most
flexibility and tuning range. The response versus ADJ code is shown below in 图 29.
In this example the deflection caused by the button press (∆d) is 2mm. Note that the ∆d must be enough to cross
the “Switch ON” threshold and return past “Switch OFF” threshold of the LDC0851 for a given ADJ code to be
considered a valid code. Codes 0 through 6 should not be used because the conductive target has already
crossed the "Switch ON" thresholds and would always be in the ON state without a button push. Similarly code
15 should not be used because the output would always be in an OFF state regardless of how hard the button is
pushed. Therefore codes 8 through 14 are clearly inside the travel distance of the button. Select code 8 to detect
light button pushes, code 11 for medium button pushes, or code 14 to only detect strong button pushes. Once
the ADJ code is selected based on user preference, set the resistor divider R1 and R2 values according to
section Setting the Threshold Adjust Values.
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Typical Application (接下页)
9.2.2.3 Application Curves
图 29. Threshold Adjust Design Space for 10mm Coil Example
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Typical Application (接下页)
9.2.3 Low Power Operation
It may be desirable to operate the LDC0851 on battery power and take samples at a very low sample rate, such
as portable sensor devices or intruder detection systems. By using a nanotimer (ultra low power timer) such as
the TPL5110 or a microcontroller such as the MSP430F5500 it is possible to duty cycle the EN pin of the
LDC0851 as shown in the application schematic in 图 30.
3-V Battery
Wake up LDC
VDD
EN
Sense
Coil
R1
R2
LSENSE
ADJ
LDC0851
µC
LCOM
LREF
Sensor
Cap
High/Low Output
OUT
Reference
Coil
GND
图 30. Application Schematic Showing Low Power Operation
9.2.3.1 Design Requirements
The LDC0851 is used in a low power, battery operated system to detect when a window is opened. Determine
the average supply current of the LDC0851 if following requirements exist:
1. A lifetime of greater than 10 years is required from a single CR2032 battery which supplies the power for the
LDC0851.
2. A microcontroller can be used to wakeup the LDC0851 and capture the high/low output state.
3. At least 1 sample per second (ƒSAMPLE) is required to detect if the window is open or closed.
9.2.3.2 Detailed Design Procedure
In order to achieve 10 year lifetime out of a single CR2032 battery, the enable pin (EN) of the LDC0851 can be
duty cycled to achieve a low average supply current. Refer to 图 31 to see the three different states of LDC0851
supply current during duty cycle operation. The sum of the Standby, Ramp, and On currents can be used to
calculate the average supply current of the LDC0851, which needs to be below 2.5 µA to achieve a 10 year
lifetime from a 220 mAh CR2032 battery.
The average supply current can be calculated in the following steps:
1. Select desired system sample rate (ƒSAMPLE) based on the given application. In this example, ƒSAMPLE is 1
sample per second.
2. Select the sensor characteristics (ƒSENSOR, LSENSOR, CSENSOR) based on conversion time and current
consumption.
(a) ƒSENSOR should be increased as much as possible to minimize the conversion time. 10 MHz is chosen as
a starting point.
(b) LSENSOR should be increased as much as possible to decrease the sensor current (ISENSOR). Based on a
reasonable PCB area, 10 µH is a good starting point.
(c) CSENSOR is calculated to be 34.5 pF from 公式 8 using the inputs above. This makes CTOTAL equal to 50.5
pF which meets the requirement of greater than 33 pF to be inside the design space.
3. Calculate the average active current:
ION = ƒSAMPLE ì(2ìtCONVERSION)ì(IDD
)
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Typical Application (接下页)
where:
•
•
•
•
ƒSAMPLE is the number of samples per second given from step 1. In this example, ƒSAMPLE is equal to 1.
tCONVERSION is calculated from 公式 2 to give a conversion time of 433 µs.
IDD is the total active supply current given by 公式 5 to be 1.587 mA.
ION is the active current consumed by the LDC0851 which comes to be 1.37 µA.
(10)
4. Calculate the average ramp current:
I
≈
’
DD
IRAMP = ƒSAMPLE ì(tAMT )ì
∆
«
÷
◊
2
where:
•
•
•
•
ƒSAMPLE is the number of samples per second given from step 1. In this example, ƒSAMPLE is equal to 1.
tAMT is the active mode transition time given in the electrical table as typically 450µs.
IDD is the total active supply current given by 公式 5 to be 1.587 mA.
IRAMP is the current consumed by the LDC0851 before a conversion has started which comes to be 0.357 µA.
(11)
5. Calculate the average standby current:
IOFF = (1- ƒSAMPLE ì(tAMT - 2ìtCONVERSION))ì(ISD
)
where:
•
•
•
•
•
ƒSAMPLE is the number of samples per second given from step 1. In this example, ƒSAMPLE is equal to 1.
tAMT is the active mode transition time given in the electrical table as typically 450µs.
tCONVERSION is calculated from 公式 2 to give a conversion time of 433 µs.
ISD is the shutdown current of the LDC0851 given in the electrical table as typically 140nA.
IOFF is the standby current of the LDC0851 which comes to be 0.140 µA.
(12)
6. Calculate the total average supply current:
IAVG = ION +IRAMP +IOFF
where:
•
•
•
•
ION is the active supply current given from 公式 10 to be 1.37 µA.
IRAMP is the ramp current given by 公式 11 to be 0.357 µA.
IOFF is the standby current given by 公式 12 to be 0.140 µA.
IAVG is the average supply current consumed per second which comes to 1.867 µA.
(13)
7. Finally the lifetime of the battery can be calculated:
Battery Capacity
Battery Lifetime (years) =
IAVG
where:
•
Battery Capacity is the amount of charge x time that the battery can hold in mAh. This example uses a
CR2032 battery with 220 mAh.
•
•
IAVG is the value reported in 公式 13 to be 1.867 µA.
Battery Lifetime (years) is how long the battery will last reported in years which comes out to be 13.5 years
with the inputs from above.
(14)
For example, using a sensor frequency of 10 MHz, sensor inductance of 10 µH, and 1 sample per second yields
a lifetime of 13.5 years for a single CR2032 battery.
26
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Typical Application (接下页)
9.2.3.3 Application Curves
I
IDD
IDD
2
ISD
ISD
t
tOFF
(Standby)
tAMT
(Ramp)
tON
(On)
图 31. LDC0851 Supply Current vs. Time During Duty Cycle Operation
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10 Power Supply Recommendations
A 0.1 µF capacitor should be used to bypass VDD. If multiple bypass capacitors are used in the system, then the
smallest value capacitor should be placed as close as possible to the VDD pin. A ground plane is recommended
to connect both the ground and the Die Attach Pad (DAP). If the supply ramp rate must be faster than 4.2 mV/µs
the enable pin (EN) may be tied directly to VDD as shown in 图 32.
VDD
LDC0851
Fast
Supply
0.1 µF
(> 4.2 mV / µs)
EN
Power
Management
GND
DAP
图 32. Supply Connections for Fast Ramp Rate
For supply ramp rates slower than 4.2 mV/µs, an RC low pass filter must be added to the enable input (EN) as
shown in 图 33. Alternatively, the EN pin may be tied to a nanotimer or microcontroller to wake up the LDC0851
after VDD has ramped to its nominal value.
VDD
LDC0851
Slow
Supply
0.1 µF
(< 4.2 mV / µs)
R
EN
Power
Management
C
GND
DAP
图 33. Supply Connections for Slow Ramp Rate
For applications that require low power, the EN pin may toggled with a GPIO or nanotimer to duty cycle the
device and achieve ultra-low power consumption. Although the device may be power cycled to achieve a similar
effect, some systems may not have a clean GPIO to supply the LDC0851 or the filtering on the supply may add a
time constant delay which can make the use of the EN pin much more efficient and desirable for duty cycled
applications. Refer to Low Power Operation for a detailed design example.
28
版权 © 2015–2016, Texas Instruments Incorporated
LDC0851
www.ti.com.cn
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
11 Layout
11.1 Layout Guidelines
The LDC0851 requires minimal external components for effective operation. An LDC0851 design should follow
good layout techniques - providing good grounding and clean supplies are critical for optimum operation. Due to
the small physical size of the LDC0851, use of surface mount 0402 or smaller components can ease routing. It is
important to keep the routing symmetrical and minimize parasitic capacitances for LSENSE and LREF. The
sensor capacitor should be placed close to the IC and keep traces far apart to minimize the effects of parasitic
capacitance. For optimum performance, it is recommended to use a C0G/NP0 for the sensor capacitor.
11.2 Layout Example
11.2.1 Side by Side Coils
The use of side by side coils is recommended for many applications that require a 2 layer PCB or that require
very accurate temperature compensation. For side by side coils it is recommended to put them on the same
PCB, even if using a remote sensing application. This will keep the tolerances and mismatch between the coils
as small as possible. An example layout of side by side coils is shown in 图 34.
图 34. Side by Side Coil Layout Example
版权 © 2015–2016, Texas Instruments Incorporated
29
LDC0851
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
www.ti.com.cn
Layout Example (接下页)
11.2.2 Stacked Coils
Use of stacked coils may be desirable to conserve board space and to prevent false triggering when a target
approaches from the bottom. A 4 layer PCB with a thick inner layer is recommended to achieve the best results.
It is important to note the direction and polarity of the sense coil and reference coils with respect to each other.
The recommended configuration is shown below.
LSENSE
Counter-Clockwise
Out Spiral on Layer 1
Via from Layer 1 to
Layer 2
LCOM
Clockwise Out
Spiral on Layer 2
Sensor
Capacitor
Via from Layer 2 to
Layer 3
Clockwise Out
Spiral on Layer 3
Via from Layer 3 to
Layer 4
LREF
Counter-Clockwise
Out Spiral on Layer 4
图 35. Stacked Coil Recommended Connections and Direction
30
版权 © 2015–2016, Texas Instruments Incorporated
LDC0851
www.ti.com.cn
ZHCSET4A –DECEMBER 2015–REVISED JANUARY 2016
12 器件和文档支持
12.1 器件支持
12.1.1 开发支持
要获取在线 LDC 系统设计工具，请访问德州仪器的 Webench® 工具
LDC 计算器工具提供了一系列在 MS Excel®下运行的计算工具，这些工具对于 LDC 的系统开发非常有用。
12.2 社区资源
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.
12.3 商标
E2E is a trademark of Texas Instruments.
Webench is a registered trademark of Texas Instruments.
Excel is a registered trademark of Microsoft Corporation.
12.4 静电放电警告
这些装置包含有限的内置 ESD 保护。 存储或装卸时，应将导线一起截短或将装置放置于导电泡棉中，以防止 MOS 门极遭受静电损
伤。
12.5 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
13 机械、封装和可订购信息
以下页中包括机械、封装和可订购信息。这些信息是针对指定器件可提供的最新数据。这些数据会在无通知且不对
本文档进行修订的情况下发生改变。欲获得该数据表的浏览器版本，请查阅左侧的导航栏
版权 © 2015–2016, Texas Instruments Incorporated
31
PACKAGE OPTION ADDENDUM
www.ti.com
19-Nov-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)
LDC0851HDSGR
LDC0851HDSGT
ACTIVE
ACTIVE
WSON
WSON
DSG
DSG
8
8
3000 RoHS & Green
250 RoHS & Green
NIPDAU
Level-1-260C-UNLIM
Level-1-260C-UNLIM
-40 to 125
-40 to 125
0851
0851
Samples
Samples
NIPDAU
(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 OPTION ADDENDUM
www.ti.com
19-Nov-2022
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
17-Mar-2016
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)
LDC0851HDSGR
LDC0851HDSGT
WSON
WSON
DSG
DSG
8
8
3000
250
180.0
180.0
8.4
8.4
2.3
2.3
2.3
2.3
1.15
1.15
4.0
4.0
8.0
8.0
Q2
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
17-Mar-2016
*All dimensions are nominal
Device
Package Type Package Drawing Pins
SPQ
Length (mm) Width (mm) Height (mm)
LDC0851HDSGR
LDC0851HDSGT
WSON
WSON
DSG
DSG
8
8
3000
250
210.0
210.0
185.0
185.0
35.0
35.0
Pack Materials-Page 2
GENERIC PACKAGE VIEW
DSG 8
2 x 2, 0.5 mm pitch
WSON - 0.8 mm max height
PLASTIC SMALL OUTLINE - NO LEAD
This image is a representation of the package family, actual package may vary.
Refer to the product data sheet for package details.
4224783/A
www.ti.com
PACKAGE OUTLINE
DSG0008A
WSON - 0.8 mm max height
SCALE 5.500
PLASTIC SMALL OUTLINE - NO LEAD
2.1
1.9
B
A
0.32
0.18
PIN 1 INDEX AREA
2.1
1.9
0.4
0.2
ALTERNATIVE TERMINAL SHAPE
TYPICAL
0.8
0.7
C
SEATING PLANE
0.05
0.00
SIDE WALL
0.08 C
METAL THICKNESS
DIM A
OPTION 1
0.1
OPTION 2
0.2
EXPOSED
THERMAL PAD
(DIM A) TYP
0.9 0.1
5
4
6X 0.5
2X
1.5
9
1.6 0.1
8
1
0.32
0.18
PIN 1 ID
(45 X 0.25)
8X
0.4
0.2
8X
0.1
C A B
C
0.05
4218900/E 08/2022
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. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.
www.ti.com
EXAMPLE BOARD LAYOUT
DSG0008A
WSON - 0.8 mm max height
PLASTIC SMALL OUTLINE - NO LEAD
(0.9)
(
0.2) VIA
8X (0.5)
TYP
1
8
8X (0.25)
(0.55)
SYMM
9
(1.6)
6X (0.5)
5
4
SYMM
(1.9)
(R0.05) TYP
LAND PATTERN EXAMPLE
SCALE:20X
0.07 MIN
ALL AROUND
0.07 MAX
ALL AROUND
SOLDER MASK
OPENING
METAL
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
NON SOLDER MASK
DEFINED
SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK DETAILS
4218900/E 08/2022
NOTES: (continued)
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
number SLUA271 (www.ti.com/lit/slua271).
5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown
on this view. It is recommended that vias under paste be filled, plugged or tented.
www.ti.com
EXAMPLE STENCIL DESIGN
DSG0008A
WSON - 0.8 mm max height
PLASTIC SMALL OUTLINE - NO LEAD
8X (0.5)
METAL
8
SYMM
1
8X (0.25)
(0.45)
SYMM
9
(0.7)
6X (0.5)
5
4
(R0.05) TYP
(0.9)
(1.9)
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
EXPOSED PAD 9:
87% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE
SCALE:25X
4218900/E 08/2022
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
www.ti.com
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