Product
Folder
Order
Now
Support &
Community
Tools &
Software
Technical
Documents
TPS92612
SLVSFG3 – APRIL 2020
TPS92612 40-V, 150-mA Single-Channel Linear LED Driver and Constant-Current Source
With Protection
1 Features
3 Description
•
With LEDs being widely used as a light source,
simple LED drivers are more and more popular.
Compared to discrete solutions, a low-cost monolithic
solution lowers system-level component counts and
significantly improves current accuracy and reliability.
1
•
•
•
•
•
•
•
Single-channel high-precision current source:
– ±4.6% Current accuracy from –40°C to +125°C
– Current adjustable by external sense resistor
– Up to 150 mA maximum current
Wide input-voltage range: 4.5 V – 40 V
Brightness control by input PWM duty cycle
Low dropout voltage (current-sense voltage drop
included)
– Maximum dropout: 150 mV at 10 mA
– Maximum dropout: 400 mV at 70 mA
– Maximum dropout: 700 mV at 150 mA
Low quiescent current: typical 200 µA
Protection:
– LED short-circuit protection with auto-recovery
– Thermal shutdown
Support heat sharing with external resistor
Operating junction temperature range: –40°C to
+150°C
The TPS92612 device is a single-channel high-side
linear LED driver operating from a wide range supply.
It is a simple, yet elegant solution to deliver constant
current for a single LED string. It can support offboard LED connection with long cables. The
TPS92612 device can also be used as a general
constant current source or current limiter in other
applications.
Device Information(1)
PART NUMBER
TPS92612
PACKAGE
BODY SIZE (NOM)
SOT-23 (5)
2.9 mm × 1.6 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application Diagram
4.5 ± 40V
2 Applications
•
LED driver, constant current source, or current
limiter for:
– Washer and dryer
– Refrigerator and freezer
– Gas detector
– Factory automation and control
– Building automation
– Medical
R(SNS)
TPS92612
C(SUPPLY)
PWM
SUPPLY
IN
C(OUT)
PWM
GND
OUT
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.
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
3
6.1
6.2
6.3
6.4
6.5
6.6
6.7
3
3
4
4
4
4
5
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Timing Requirements ................................................
Typical Characteristics ..............................................
7.3 Feature Description................................................... 8
7.4 Device Functional Modes.......................................... 9
8
Application and Implementation ........................ 10
8.1 Application Information............................................ 10
8.2 Typical Application .................................................. 10
9 Power Supply Recommendations...................... 14
10 Layout................................................................... 15
10.1 Layout Guidelines ................................................. 15
10.2 Layout Example .................................................... 15
11 Device and Documentation Support ................. 16
11.1
11.2
11.3
11.4
11.5
Detailed Description .............................................. 8
7.1 Overview ................................................................... 8
7.2 Functional Block Diagram ......................................... 8
Receiving Notification of Documentation Updates
Support Resources ...............................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
16
16
16
16
16
12 Mechanical, Packaging, and Orderable
Information ........................................................... 16
4 Revision History
2
DATE
REVISION
NOTES
April 2020
*
Initial release.
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
TPS92612
www.ti.com
SLVSFG3 – APRIL 2020
5 Pin Configuration and Functions
TPS92612 DBV Package
5-Pin SOT-23
Top View
GND
1
PWM
2
SUPPLY
3
5
OUT
4
IN
Not to scale
Pin Functions
PIN
NAME
NO.
I/O
DESCRIPTION
TPS92612
GND
1
—
Ground
IN
4
I
Current input
OUT
5
O
Constant-current output
PWM
2
I
PWM input
SUPPLY
3
I
Device supply voltage
6 Specifications
6.1 Absolute Maximum Ratings
over operating ambient temperature range (unless otherwise noted) (1)
MIN
MAX
High-voltage input
IN, PWM, SUPPLY
–0.3
45
V
High-voltage output
OUT
–0.3
45
V
IN to OUT
V(IN) – V(OUT)
–0.3
45
V
SUPPLY to IN
V(SUPPLY) – V(IN)
–0.3
1
V
Operating junction temperature, TJ
–40
150
°C
Storage temperature, Tstg
–40
150
°C
(1)
UNIT
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.
6.2 ESD Ratings
VALUE
Human-body model (HBM), per ANSI/ESDA/JEDEC
JS-001 (1)
V(ESD)
(1)
(2)
Electrostatic discharge
Charged-device model (CDM), per JEDEC
specification JESD22-C101 (2)
All pins
±2000
All pins
±500
Corner pins (3, 4, and 5)
±750
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safemanufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safemanufacturing with a standard ESD control process.
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
3
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
6.3 Recommended Operating Conditions
over operating ambient temperature range (unless otherwise noted)
MIN
NOM
MAX
UNIT
SUPPLY
Device supply voltage
4.5
40
V
IN
Sense voltage
4.4
40
V
PWM
PWM inputs
0
40
V
OUT
Driver output
0
40
V
–40
125
°C
Operating ambient temperature, TA
6.4 Thermal Information
TPS92612
THERMAL METRIC
DBV (SOT23)
UNIT
5 PINS
RθJA
Junction-to-ambient thermal resistance
200.7
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
104.4
°C/W
RθJB
Junction-to-board thermal resistance
45.6
°C/W
ψJT
Junction-to-top characterization parameter
17.5
°C/W
ψJB
Junction-to-board characterization parameter
45.2
°C/W
6.5 Electrical Characteristics
V(SUPPLY) = 5 V to 40 V, TJ = –40°C to +150°C unless otherwise noted
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
3.2
4
UNIT
BIAS
V(POR_rising)
Supply voltage POR rising threshold
V(POR_falling)
Supply voltage POR falling threshold
I(Quiescent)
Device standby current
PWM = HIGH
V
2.2
3
0.1
0.2
0.25
mA
V
LOGIC INPUTS (PWM)
VIL(PWM)
Input logic-low voltage, PWM
1.045
1.1
1.155
V
VIH(PWM)
Input logic-high voltage, PWM
1.16
1.2
1.24
V
150
mA
CONSTANT-CURRENT DRIVER
I(OUT)
Device output-current range
V(CS_REG)
Sense-resistor regulation voltage
R(CS_REG)
Sense-resistor value
V(DROPOUT)
100% duty cycle
4
TA = 25°C, V(SUPPLY) = 4.5 V to 18 V
TA = –40°C to +125°C, V(SUPPLY) = 4.5 V to 18 V
94
98
102
93.5
98
102.5
0.66
Voltage dropout from SUPPLY to OUT
24.5
V(CS_REG) voltage included, current setting of 10 mA
120
150
V(CS_REG) voltage included, current setting of 70 mA
250
400
V(CS_REG) voltage included, current setting of 150
mA
430
700
mV
Ω
mV
DIAGNOSTICS
V(SG_th_rising)
Channel output V(OUT) short-to-ground
rising threshold
1.14
1.2
1.26
V
V(SG_th_falling)
Channel output V(OUT) short-to-ground
falling threshold
0.82
0.865
0.91
V
I(Retry)
Channel output V(OUT) short-to-ground
retry current
0.64
1.08
1.528
mA
157
172
187
°C
THERMAL PROTECTION
T(TSD)
Thermal shutdown junction temperature
threshold
T(TSD_HYS)
Thermal shutdown junction temperature
hysteresis
15
°C
6.6 Timing Requirements
t(PWM_delay_rising)
4
PWM rising edge delay, 50% PWM voltage to 10% of output current closed loop, t2 - t1 as shown
in Figure 1
Submit Documentation Feedback
MIN
NOM
MAX
10
17
25
UNIT
µs
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
TPS92612
www.ti.com
SLVSFG3 – APRIL 2020
Timing Requirements (continued)
t(PWM_delay_falling)
PWM falling edge delay, 50% PWM voltage to 90% of output current open loop, t5 - t4 as shown
in Figure 1
t(DEVICE_STARTUP)
SUPPLY rising edge to 10% output current at 50-mA set current, t8 - t7 as shown
in Figure 1
t(SG_deg)
Output short-to-ground detection deglitch time
t(TSD_deg)
Thermal over temperature deglitch timer
t(Recover_deg)
Fault recovery deglitch timer
MIN
NOM
MAX
15
21
30
µs
100
150
µs
125
175
µs
80
UNIT
50
8.5
16
µs
25
µs
SUPPLY
Input duty-cycle
PWM
90%
90%
IOUT
Output duty-cycle
t1
10%
10%
10%
t2
t3
t4
t5
t6
t8
t7
Figure 1. Output Timing Diagram
6.7 Typical Characteristics
250
200
I(OUT) setting = 10 mA
I(OUT) setting = 70 mA
I(OUT) setting = 150 mA
I(OUT) setting (mA)
Output Current (mA)
200
150
100
50
100
70
50
30
20
10
7
5
3
0
4
10
16
22
28
Supply Voltage (V)
34
40
2
0.6
D001
1
2
3 4 5 6 7 8 10
R(SNS) (:)
20
30
TA = 25 °C
Figure 2. Output Current vs Supply Voltage
Figure 3. Output Current vs Current-Sense Resistor
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
5
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
Typical Characteristics (continued)
240
180
I(OUT) setting = 10 mA
I(OUT) setting = 70 mA
I(OUT) setting = 150 mA
150
Output Current (mA)
Outout Current (mA)
200
160
120
80
40
120
90
60
40qC
25qC
125qC
30
0
0
0
0.5
1
Dropout Voltage (V)
1.5
2
0
TA = 25 °C
1
Dropout Voltage (V)
1.5
2
D003
I(OUT) setting = 150 mA
Figure 4. Output Current vs Dropout Voltage
Figure 5. Output Current vs Dropout Voltage
250
100%
Output Current Duty Cycle
Output Current (mA)
0.5
D002
200
150
100
10%
1%
50
-40
-20
0
20
40
60
80
Temperature (oC)
I(OUT) setting = 150 mA
100
120
140
V(SUPPLY)-V(OUT) = 2 V
Figure 6. Output Current vs Temperature
Ch. 1 = SUPPLY
f(PWM) = 200 Hz
Ch. 2 = V(PWM)
Duty-cycle = 50%
Ch. 4 = I(OUT)
0.5%
1%
100%
D005
f(PWM) = 200 Hz
Figure 7. PWM Output Duty Cycle vs Input Duty Cycle
Ch. 1 = SUPPLY
f(PWM) = 2 kHz
Figure 8. PWM Dimming at 200 Hz
6
10%
PWM Duty Cycle
Submit Documentation Feedback
Ch. 2 = V(PWM)
Duty-cycle = 50%
Ch. 4 = I(OUT)
Figure 9. PWM Dimming at 2 kHz
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
TPS92612
www.ti.com
SLVSFG3 – APRIL 2020
Typical Characteristics (continued)
Ch. 1 = SUPPLY
Ch. 2 = V(OUT)
Ch. 4 = I(OUT)
Figure 10. LED Open-Circuit and Recovery
Ch. 1 = SUPPLY
Ch. 2 = V(OUT)
Ch. 4 = I(OUT)
Figure 11. LED Short-Circuit Protection and Recovery
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
7
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
7 Detailed Description
7.1 Overview
The TPS92612 device is a single-channel linear LED driver providing a simple current source with protection.
The output current at OUT pin can be set by an external R(SNS) resistor. Current flows from the supply through
the R(SNS) resistor into the integrated current regulation circuit and to the output through OUT pin. Brightness can
be controlled by PWM pin.
7.2 Functional Block Diagram
4.5 ± 40V
TPS92612
R(SNS)
IN
PWM
Supply
and
Control
±
+
SUPPLY
Output Driver
OUT
GND
7.3 Feature Description
7.3.1 Device Bias
7.3.1.1 Power-On Reset (POR)
The TPS92612 device has an internal power-on-reset (POR) function. When power is applied to the SUPPLY
pin, the internal POR holds the device in the reset condition until V(SUPPLY) reaches V(POR_rising).
7.3.2 Constant-Current Driver
The TPS92612 device is a high-side constant-current driver. The device controls the output current through
regulating the voltage drop on an external high-side current-sense resistor, R(SNS). An integrated error amplifier
drives an internal power transistor to maintain the voltage drop on the current-sense resistor R(SNS) to V(CS_REG)
and therefore regulates the current output to target value. When the output current is in regulation, the current
value can be calculated by using Equation 1.
I(OUT)
V(CS _ REG)
R(SNS)
where
•
8
V(CS_REG) = 98 mV (typical)
(1)
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
TPS92612
www.ti.com
SLVSFG3 – APRIL 2020
Feature Description (continued)
When the SUPPLY-to-OUT voltage difference is below the required dropout voltage, V(DROPOUT), at a given
output current, the TPS92612 is not able to deliver enough current output as set by the value of R(SNS), and the
voltage across the current-sense resistor R(SNS) is less than V(CS_REG).
7.3.3 PWM Control
The pulse width modulation (PWM) input of the TPS92612 functions as enable for the output current. When the
voltage applied on the PWM pin is higher than VIH(PWM), the output current is enabled. When the voltage applied
on PWM pin is lower than VIL(PWM), the output current is disabled. Besides output current enable and disable
function, the PWM input of TPS92612 also supports adjustment of the average current for LED brightness
control. TI recommends a 200 Hz – 2 kHz PWM signal for brightness control, which is out of visible frequency
range of human eyes.
7.3.4 Protection
7.3.4.1 Short-to-GND Protection
The TPS92612 device has OUT short-to-GND protection. The device monitors the V(OUT) voltage when the
output current is enabled and compares it with the internal reference voltage to detect a short-to-GND failure. If
V(OUT) falls below V(SG_th_falling) longer than the deglitch time of t(SG_deg), the device asserts the short-to-GND fault.
During the deglitching time period, if V(OUT) rises above V(SG_th_rising), the timer is reset.
Once the device has detected a short-to-GND fault, the device turns off the output channel and retries
automatically by sourcing a small current I(retry) from IN to OUT to pull up the loads continuously, regardless of
the state of the PWM input. Once auto retry detects output voltage rising above V(SG_th_rising), the device clears
the short-to-GND fault and resumes normal operation.
7.3.4.2 Over Temperature Protection
The TPS92612 device monitors device junction temperature. When the junction temperature reaches thermal
shutdown threshold T(TSD), the output shuts down. Once the junction temperature falls below T(TSD) – T(TSD_HYS),
the device recovers to normal operation.
7.4 Device Functional Modes
7.4.1 Undervoltage Lockout, V(SUPPLY)< V(POR_rising)
When the TPS92612 device is in undervoltage lockout mode, the device disables all functions until the supply
rises above the V(POR_rising) threshold.
7.4.2 Normal State, V(SUPPLY) ≥ 4.5 V
The device regulates output current in normal state. With enough voltage drop across SUPPLY and OUT, the
device is able to drive the output in constant-current mode.
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
9
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
8 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.
8.1 Application Information
The TPS92612 device is a constant-current regulator which can be used as a LED driver, general constantcurrent source or current limiter in industrial applications.
Thermal performance is one of the design challenges for linear devices. To increase current-driving capability,
the device supports heat sharing using an external parallel resistor, as shown in Figure 15. This technique
provides the low-cost solution of using external resistors to minimize thermal accumulation on the device itself,
and still keeps high accuracy of the total current output.
8.2 Typical Application
8.2.1 Single LED Driver
The TPS92612 offers a cost-effective and easy-to-use solution for LED driver applications. PWM input can be
adopted for LED brightness adjust and LED ON/OFF control. The device also supports off-board LED connection
with long cables.
5V
R(SNS)
TPS92612
C(SUPPLY)
PWM
SUPPLY
IN
Long wire impedence
PWM
OUT
GND
C(OUT)
Figure 12. Typical Application Diagram
8.2.1.1 Design Requirements
The input voltage is 5 V ± 5%. LED maximum forward voltage VF_MAX = 2.5 V, minimum forward voltage VF_MIN =
1.9 V, current I(LED) = 150 mA. LED is connected to device OUT pin through a 1-m long wire.
8.2.1.2 Detailed Design Procedure
STEP 1: Determine the current setting resistor, R(SNS) value by using Equation 2.
V(CS _ REG)
R(SNS)
0.653:
I(LED)
where
•
•
V(CS_REG) = 98 mV (typical)
I(LED) = 150 mA
(2)
STEP 2: Power consumption analysis for the worst application conditions.
10
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
TPS92612
www.ti.com
SLVSFG3 – APRIL 2020
Typical Application (continued)
Normally the thermal analysis is necessary for linear LED-driver applications to ensure that the operation junction
temperature of TPS92612 is well managed. The total power consumption on the TPS92612 itself is one
important factor determining operation junction temperature, and it can be calculated by using Equation 3. Based
on the worst-case analysis for maximum power consumption on device, consider either optimizing PCB layout for
better power dissipation as Layout describes or adding an extra heat-sharing resistor as described in SingleChannel LED Driver With Heat Sharing.
P DEV
V SUPPLY
P DEV _ MAX
V CS _ REG
V OUT u I LED
V SUPPLY u I Quiescent
5.25 0.098 1.9 u 0.15 5.25 u 0.00025
0.489W
where
•
•
V(CS_REG) = 98 mV (typical)
I(Quiescent) = 250 µA (maximum)
(3)
In this application, the calculated result for maximum power consumption on the TPS92612 is 0.489 W at
V(SUPPLY) = 5.25 V and I(LED) = 150 mA conditions.
TI recommends to add capacitors C(SUPPLY) at SUPPLY and C(OUT) at OUT. TI recommends one 1-μF capacitor
plus one 100-nF decoupling ceramic capacitor close to the SUPPLY pin for C(SUPPLY) and a 10-nF ceramic
capacitor close to the OUT pin for C(OUT). The larger capacitor for C(SUPPLY) or C(OUT) is helpful for EMI and ESD
immunity; however, large C(OUT) takes a longer time to charge up the capacitor and may affect PWM dimming
performance.
8.2.1.3 Application Curve
A 1-μH inductor is connected between OUT and the LED to simulate the 1-m long cable.
Ch. 1 = V(SUPPLY)
Ch. 3 = V(OUT)
Ch. 2 = V(PWM)
Ch. 4 = I(OUT)
Figure 13. Output Current With PWM Input
Ch. 1 = V(SUPPLY)
Ch. 3 = V(OUT)
Ch. 2 = V(PWM)
Ch. 4 = I(OUT)
Figure 14. Output Current With PWM Input
8.2.2 Single-Channel LED Driver With Heat Sharing
Using parallel resistors, thermal performance can be improved by balancing current between the TPS92612
device and the external resistors as follows. As the current-sense resistor controls the total LED string current,
the LED string current I(LED) is set by V(CS_REG) / R(SNS), while the TPS92612 current I(DRIVE) and parallel resistor
current I(P) combine to the total current.
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
11
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
Typical Application (continued)
12 V
R(SNS)
TPS92612
SUPPLY
I(DRIVE)
IN
C(SUPPLY)
R(P)
PWM
GND
I(LED)
I(P)
C(OUT)
OUT
Figure 15. Heat Sharing With a Parallel Resistor
8.2.2.1 Design Requirements
The input voltage range is 12 V ± 10%, LED maximum forward voltage VF_MAX = 2.5 V, minimum forward voltage
VF_MIN = 1.9 V, current I(LED) = 150 mA.
8.2.2.2 Detailed Design Procedure
In linear LED driver applications, the input and output voltage variation generates the most of the thermal
concerns. The resistor current I(P), as indicated by Ohm's law, depends on the voltage across the external
resistors. The TPS92612 controls the driver current I(DRIVE) to attain the desired total current. If I(P) increases, the
TPS92612 device decreases I(DRIVE) to compensate, and vice versa. The parallel-resistor takes highest current
and generates maximum heat at maximum supply voltage and minimum LED-string forward voltage.
The parallel resistor value must be carefully calculated to ensure that 1) thermal dissipation for both the
TPS92612 device and the resistor is within their thermal dissipation limits, and 2) device current at high voltage
drop condition is above the minimal output-current requirement.
STEP 1: Determine the current setting resistor, R(SNS) value by using Equation 4.
V(CS _ REG)
R(SNS)
0.653:
I(LED)
where
•
•
V(CS_REG) = 98 mV (typical)
I(LED) = 150 mA
(4)
The calculated result for R(SNS) is 0.653 Ω.
STEP 2: Calculate the parallel resistor, R(P) value by using Equation 5.
The parallel resistor R(P) is recommended to consume 50% of the total current at maximum supply voltage and
minimum LED-string forward voltage.
V(SUPPLY) V(CS _ REG) V(OUT) 13.2 0.098 3 u 1.9
R(P)
| 100:
0.5 u I(LED)
0.5 u 0.15
where
•
•
V(CS_REG) = 98 mV (typical)
I(LED) = 150 mA
(5)
The calculated result for R(P) is about 100 Ω at V(SUPPLY) = 13.2 V.
STEP 3: Power consumption analysis for the worst application conditions.
The total device power consumption can be calculated by Equation 6.
12
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
TPS92612
www.ti.com
SLVSFG3 – APRIL 2020
Typical Application (continued)
P DEV
§
V SUPPLY V CS _ REG V OUT ·
¸ V
V OUT u ¨ I LED
SUPPLY u I Quiescent
RP
¨
¸
©
¹
13.2 0.098 3 u 1.9 ·
§
13.2 0.098 3 u 1.9 u ¨ 0.15
¸ 13.2 u 0.00025 0.566W
100
©
¹
V SUPPLY
P DEV _ MAX
V CS _ REG
where
•
•
V(CS_REG) = 98 mV (typical)
I(Quiescent) = 250 µA (maximum)
(6)
The calculated maximum power consumption on the TPS92612 device is 0.566 W at V(SUPPLY) = 13.2 V, V(OUT) =
3 × 1.9 V = 5.7 V and I(LED) = 150 mA.
The power consumption on resistor R(P) can be calculated through Equation 7.
2
V SUPPLY
P RP
V CS _ REG
V OUT
RP
P RP _ MAX
13.2 0.098 3 u 1.9
100
2
0.548W
where
•
V(CS_REG) = 98 mV (typical)
(7)
The calculated maximum power consumption on the 100 Ω, R(P) parallel resistor is 0.548 W at V(SUPPLY) = 13.2 V
and V(OUT) = 3 × 1.9 V = 5.7 V.
TI recommends adding capacitors C(SUPPLY) at SUPPLY and C(OUT) at OUT. One 1-μF capacitor plus one 100-nF
decoupling ceramic capacitor close to the SUPPLY pin is recommended for C(SUPPLY), and a 10-nF ceramic
capacitor close to the OUT pin is recommended for C(OUT). The larger capacitor for C(SUPPLY) or C(OUT) is helpful
for EMI and ESD immunity, however large C(OUT) takes a longer time to charge up the capacitor and could affect
PWM dimming performance.
Note that the parallel resistor path cannot be shut down by PWM or fault protection. If PWM control is required,
TI recommends an application circuit as shown in Figure 16. A NPN bipolar transistor with a base current-limiting
resistor, R1, can modulate the output current together with the device PWM function. The resistor value of R1
needs to be calculated based on the applied PWM voltage and β value of selected NPN transistor.
12 V
R(SNS)
TPS92612
SUPPLY
I(DRIVE)
I(LED)
IN
C(SUPPLY)
PWM
R(P)
PWM
I(P)
OUT
GND
C(OUT)
PWM
R1
Figure 16. PWM Control With Heat Sharing Resistor
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
13
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
Typical Application (continued)
8.2.2.3 Application Curve
Ch. 1 = V(SUPPLY)
Ch. 2 = V(OUT)
Ch. 3 = I(P)
Ch. 4 = I(LED)
Figure 17. Constant Output Current With Heat Sharing Resistor
9 Power Supply Recommendations
The TPS92612 is designed to operate from a power system within the range specified in the Recommended
Operating Conditions. The SUPPLY input must be protected from reverse voltage and overvoltage over 40 V.
The impedance of the input supply rail must be low enough that the input current transient does not cause drop
below LED string required forward voltage. If the input supply is connected with long wires, additional bulk
capacitance may be required in addition to normal input capacitor.
14
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
TPS92612
www.ti.com
SLVSFG3 – APRIL 2020
10 Layout
10.1 Layout Guidelines
Thermal dissipation is the primary consideration for TPS92612 layout. TI recommends good thermal dissipation
area beneath the device for better thermal performance.
10.2 Layout Example
GND
TPS92612
OUT
GND
PWM
SUPPLY
SUPPLY
IN
Figure 18. TPS92612 Example Layout Diagram
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
15
TPS92612
SLVSFG3 – APRIL 2020
www.ti.com
11 Device and Documentation Support
11.1 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.2 Support Resources
TI E2E™ support forums are an engineer's go-to source for fast, verified answers and design help — straight
from the experts. Search existing answers or ask your own question to get the quick design help you need.
Linked content is 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.
11.3 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
11.4 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
11.5 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
16
Submit Documentation Feedback
Copyright © 2020, Texas Instruments Incorporated
Product Folder Links: TPS92612
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
TPS92612DBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
22SF
(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
工商网监
湘ICP备2023018690号
