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TPS22941, TPS22942, TPS22943, TPS22944, TPS22945
SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
TPS2294x Low-input-voltage Current-limited Load Switches With Shut Off And AutoRestart Feature
1 Features
3 Description
•
•
The TPS22941/2/3/4/5 load switches provide
protection to systems and loads in high-current
conditions. The devices contain a 0.4-Ω currentlimited P-channel MOSFET that can operate over an
input voltage range of 1.62 V to 5.5 V. Current is
prevented from flowing when the MOSFET is off. The
switch is controlled by an on/off input (ON), which is
capable of interfacing directly with low-voltage control
signals. The TPS22941/2/3/4/5 includes thermal
shutdown protection that prevents damage to the
device when a continuous over-current condition
causes excessive heating by turning off the switch.
1
•
•
•
•
•
•
•
•
•
•
•
•
Input Voltage Range: 1.62 V to 5.5 V
Low ON resistance
– rON = 0.4 Ω at VIN = 5.5 V
– rON = 0.5 Ω at VIN = 3.3 V
– rON = 0.6 Ω at VIN = 2.5 V
– rON = 0.8 Ω at VIN = 1.8 V
Minimum Current Limit: 40 mA or 100 mA
Undervoltage Lockout (UVLO)
Thermal Shutdown
Shutdown Current < 1 μA
Fast Current Limit Response Time
Fault Blanking
Auto Restart
1.8-V Compatible Control Input Thresholds
ESD Performance Tested Per JESD 22
– 4000-V Human-Body Model
(A114-B, Class II)
– 1000-V Charged-Device Model (C101)
Tiny SC-70 (DCK) Package
UL Recognized Component (UL File 169910)
Evaluated to IEC 60950-1, Ed 2, Am1, Annex CC,
Test Program 2 with CB Report
2 Applications
•
•
•
•
•
•
•
Low-Current Sensor Protection
HDMI Connector Protection
Notebooks
PDAs
GPS Devices
MP3 Players
Peripheral Ports
These devices provide an integrated, robust solution
to provide current limiting the output current to a safe
level by switching into a constant-current mode when
the ouptut load exceeds the current-limit threshold.
The OC logic output asserts low during overcurrent,
undervoltage, or overtemperature conditions. These
additional features make the TPS22941/2/3/4/5 an
ideal solution for applications where current limiting is
necessary.
This family of devices are available in a SC70-5
(DCK) package. It is characterized for operation over
the free-air temperature range of –40°C to 85°C.
Device Information(1)
PART NUMBER
PACKAGE
BODY SIZE (NOM)
TPS22941
TPS22942
TPS22943
SC70 (5)
2.00mm × 2.10 mm
TPS22944
TPS22945
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
1.0
ON-State Resistance, rON (W)
0.9
0.8
0.7
0.6
0.5
0.4
0.3
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Input Voltage, VIN (V)
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.
TPS22941, TPS22942, TPS22943, TPS22944, TPS22945
SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
www.ti.com
Table of Contents
1
2
3
4
5
6
7
8
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Device Comparison Table.....................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
3
3
7.1
7.2
7.3
7.4
7.5
7.6
7.7
3
3
4
4
4
5
6
Absolute Maximum Ratings .....................................
Handling Ratings.......................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Switching Characteristics ..........................................
Typical Characteristics ..............................................
Detailed Description .............................................. 9
8.1 Overview ................................................................... 9
8.2 Functional Block Diagram ......................................... 9
8.3 Feature Description................................................... 9
8.4 Device Functional Modes........................................ 10
9
Application and Implementation ........................ 11
9.1 Application Information............................................ 11
9.2 Typical Application ................................................. 11
10 Power Supply Recommendations ..................... 15
11 Layout................................................................... 15
11.1 Layout Guidelines ................................................. 15
11.2 Layout Example .................................................... 15
11.3 Thermal Considerations ........................................ 16
12 Device and Documentation Support ................. 17
12.1
12.2
12.3
12.4
Related Links ........................................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
17
17
17
17
13 Mechanical, Packaging, and Orderable
Information ........................................................... 17
4 Revision History
Changes from Revision C (November 2009) to Revision D
•
2
Page
Added Handling Rating 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
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SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
5 Device Comparison Table
DEVICE
MINIMUM CURRENT LIMIT
(mA)
CURRENT LIMIT
BLANKING TIME (ms)
AUTO-RESTART TIME (ms)
ON PIN ACTIVITY
TPS22941
40
10
80
Active LOW
TPS22942
100
10
80
Active LOW
TPS22943
40
0
N/A
Active HIGH
TPS22944
100
0
N/A
Active HIGH
TPS22945
100
10
80
Active HIGH
6 Pin Configuration and Functions
DCK PACKAGE
(TOP VIEW)
VOUT
1
GND
2
OC
3
5
VIN
4
ON
Pin Functions
PIN
NAME
SOT (DCK)
PIN NO.
TYPE
DESCRIPTION
VOUT
1
O
Switch Output. Place ceramic bypass capacitor(s) between this terminal and GND. See the
Application Information section for more information.
GND
2
–
Ground
OC
3
O
Over current output flag: active LOW, open drain output that indicates an over current,
supply under voltage, or over temperature state.
ON
4
I
Switch control input. Do not leave floating.
VIN
5
I
Switch Input. Place ceramic bypass capacitor(s) between this terminal and GND. See the
Application Information section for more information.
7 Specifications
7.1 Absolute Maximum Ratings (1)
VI
Input voltage range
TJ
Operating junction temperature range
(1)
VIN, VOUT, ON
MIN
MAX
–0.3
6
UNIT
V
Internally Limited
°C
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating
Conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
7.2 Handling Ratings
Tstg
VESD
(1)
(2)
MIN
MAX
UNIT
–65
150
°C
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all
pins (1)
–4
4
Charged device model (CDM), per JEDEC specification
JESD22-C101, all pins (2)
–1
1
Storage temperature range
Electrostatic discharge
kV
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
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7.3 Recommended Operating Conditions
Over operating free-air temperature range (unless otherwise noted)
MIN
VIN
Input voltage
VOUT
Output voltage
TA
Ambient free-air temperature
MAX
1.62
UNIT
5.5
V
VIN
–40
85
°C
7.4 Thermal Information
TPS22941/2/3/4/5
THERMAL METRIC (1)
DCK
UNIT
5 PINS
θJA
Junction-to-ambient thermal resistance
294
θJC(top)
Junction-to-case (top) thermal resistance
59.2
θJB
Junction-to-board thermal resistance
95.4
ψJT
Junction-to-top characterization parameter
0.7
ψJB
Junction-to-board characterization parameter
93.9
θJC(bot)
Junction-to-case (bottom) thermal resistance
N/A
(1)
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
7.5 Electrical Characteristics
VIN = 1.62 V to 5.5 V, TA = –40°C to 85°C (unless otherwise noted)
PARAMETER
IIN
TEST CONDITIONS
TA
μA
Full
1
μA
Full
1
μA
IOUT = 0 mA,
VIN = 1.62 V to 5.5 V
Full
OFF-State supply current
VON = 0 V (TPS22943/4/5)
or
VON = VIN (TPS22941/2)
VIN = 3.6 V,
VOUT open
IOUT(LEAKAGE) OFF-State switch current
VON = 0 V (TPS22943/4/5)
or
VON = VIN (TPS22941/2)
VIN = 3.6 V,
VOUT short to GND
VIN = 5.5 V
VIN = 3.3 V
rON
ON-state resistance
IOUT = 20 mA
VIN = 2.5 V
VIN = 1.8 V
VIN = 1.62 V
ION
ON input leakage current
VON = VIN or GND
ILIM
Current limit
VIN = 3.3 V, VOUT = 3 V
TPS22941/3
TPS22942/4/5
Thermal shutdown
Return from shutdown
4
0.4
Full
0.5
0.6
25°C
0.5
Full
0.6
0.7
25°C
0.6
Full
0.7
0.8
25°C
0.8
Full
0.9
0.9
1.1
Full
1.2
Full
1
Full
Ω
1.1
25°C
40
65
80
100
150
200
μA
mA
140
Full
Hysteresis
(1)
40
25°C
Shutdown threshold
TSD
UNIT
80
Quiescent current
IIN(OFF)
MIN TYP (1) MAX
130
°C
10
Typical values are at VIN = 3.3 V and TA = 25°C.
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SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
Electrical Characteristics (continued)
VIN = 1.62 V to 5.5 V, TA = –40°C to 85°C (unless otherwise noted)
PARAMETER
UVLO
TEST CONDITIONS
Undervoltage shutdown
VIN increasing
Undervoltage shutdown
hysteresis
TA
MIN TYP (1) MAX
Full
1.32
1.42
Full
1.52
45
UNIT
V
mV
Control Output (OC)
Vol
OC output logic low
voltage
Ioz
OC output high leakage
current voltage
VIN = 5 V, ISINK = 10 mA
Full
VIN = 1.8 V, ISINK = 10 mA
0.1
0.2
0.1
0.3
0.5
V
μA
VIN = 5 V, Switch ON
Full
VIN = 1.8 V
Full
1.1
V
VIN = 2.5 V
Full
1.3
V
VIN = 3.3 V
Full
1.4
V
VIN = 5.5 V
Full
1.7
VIN = 1.8 V
Full
0.5
V
VIN = 2.5 V
Full
0.7
V
VIN = 3.3 V
Full
0.8
V
VIN = 5.5 V
Full
0.9
V
VIN = 1.8 V to 5 V, Switch ON
Full
1
μA
Control Input (ON)
Vih
Vil
Ii
ON high-level input
voltage
ON low-level input voltage
ON high-level input
leakage current
V
7.6 Switching Characteristics
VIN = 3.3 V, RL = 500 Ω, CL = 0.1 μF, TA = 25°C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
tON
Turn-ON time
RL = 500 Ω,
CL = 0.1 μF
60
μs
tOFF
Turn-OFF time
RL = 500 Ω,
CL = 0.1 μF
30
μs
tr
VOUT rise time
RL = 500 Ω,
CL = 0.1 μF
10
μs
tf
VOUT fall time
RL = 500 Ω,
CL = 0.1 μF
tBLANK
Over current blanking time
TPS22941/2/5
5
10
20
ms
tRSTART
Auto-restart time
TPS22941/2/5
40
80
160
ms
Short-circuit response time
μs
90
VIN = VON = 3.3 V, moderate overcurrent condition
9
μs
VIN = VON = 3.3 V, hard short
4
μs
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7.7 Typical Characteristics
1.0
1.0
0.9
VIN = 1.8 V
0.8
0.8
ON-State Resistance (W)
ON-State Resistance, rON (W)
0.9
0.7
0.6
0.5
0.7
VIN = 3.3 V
0.6
0.5
0.4
VIN = 5 V
0.4
0.3
1.5
VIN = 3.6 V
0.3
0.2
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
–40
6.0
–10
25
50
85
Input Voltage, VIN (V)
Temperature (°C)
Figure 1. rON vs VIN
Figure 2. rON vs Temperature
50
42
41
40
Quiescent Current (mA)
45
Quiescent Current (uA)
39
38
37
36
35
VIN = 5.5 V
VIN = 3.3 V
40
35
VIN = 1.8 V
30
34
33
25
32
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
–40
–10
25
50
85
Temperature (°C)
Supply Voltage (V)
Figure 4. Quiescent Current vs Temperature
Figure 3. Quiescent Current vs VIN
600
500
450
500
IIN(leakage) Current (nA)
400
IIN(leakage) Current (nA)
400
VIN = 3.3 V
300
200
300
250
200
150
100
VIN = 1.8 V
100
350
50
0
–40
–10
25
50
Temperature (°C)
Figure 5. IIN(Leakage) vs Temperature
6
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85
0
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Supply Voltage (V)
Figure 6. IIN(Leakage) vs VIN
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SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
Typical Characteristics (continued)
250
500
450
VIN = 3.3 V
200
400
IIN(off) Current (nA)
IIN(off) Current (nA)
350
150
100
VIN = 1.8 V
300
250
200
150
50
100
50
0
–40
–10
25
50
0
1.0
85
1.5
2.0
2.5
Figure 7. IIN(off) vs Temperature
3.5
4.0
4.5
5.0
5.5
6.0
1.6
1.8
2.0
Figure 8. IIN(off) vs VIN
100
6.0
50
0
VIN = 1.8 V
–50
–100
VOUT (V)
IOUT(leakage) Current (nA)
3.0
Supply Voltage (V)
Temperature (°C)
VIN = 3.3 V
5.5
VIN = 1.62 V
5.0
VIN = 1.8 V
4.5
VIN = 1.95 V
4.0
VIN = 2.3 V
3.5
VIN = 2.5 V
3.0
VIN = 2.7 V
VIN = 3.0 V
2.5
VIN = 3.3 V
2.0
–150
VIN = 3.6 V
1.5
–200
–250
VIN = 4.5 V
1.0
VIN = 5.0 V
0.5
VIN = 5.5 V
0.0
–300
–40
–10
25
50
85
-0.5
0.0
0.2
0.4
1.0
1.2
1.4
180
0.16
160
85°C
0.14
140
Current Limit (mA)
0.12
Output Current (A)
0.8
Figure 10. VOUT vs ON Threshold
Figure 9. IOUT(leakage) vs Temperature
0.18
–40°C
25°C
0.10
0.08
120
100
80
0.06
60
0.04
40
0.02
20
0
0.00
0.0
0.6
Input Voltage, VON (V)
Temperature (°C)
0.4
0.8
1.2
1.6
2.0
2.4
2.8
3.2
–40
25
85
VIN-VOUT (V)
Junction Temperature, TJ (°C)
Figure 11. ILIM vs Output Voltage (TPS22942, TPS22944,
TPS22945)
Figure 12. ILIM vs Temperature (TPS22942, TPS22944,
TPS22945)
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Typical Characteristics (continued)
80
80
TA = –40°C
TA = 85°C
TA = 25°C
70
75
Current Limit, ILIM (mA)
Current Limit, ILIM (mA)
60
50
40
30
20
70
65
10
0
60
0
0.5
1
1.5
2
2.5
3
3.5
–40
VIN – VOUT (V)
RL = 350 Ω
VIN = 3.3 V
VIN = 3.3 V
Figure 16. tON/tOFF vs Temperature
13.5
100
13.0
90
12.5
80
Restart Time (ms)
Blanking Time (ms)
RL = 350 Ω
CL = 0.1 µF
Figure 15. trise/tfall vs Temperature
12.0
11.5
70
60
50
11.0
40
10.5
–40
–10
25
50
85
Temperature (°C)
Figure 17. tBLANK vs Temperature (VIN = 3.3 V)
8
85
Figure 14. ILIM vs Temperature (TPS22941, TPS22943)
Figure 13. ILIM vs (VIN-VOUT) (TPS22941, TPS22943)
CL = 0.1 µF
25
Junction Temperature, TJ (°C)
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–40
–10
25
50
85
Temperature (°C)
Figure 18. tRESTART vs Temperature (VIN = 3.3 V)
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SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
8 Detailed Description
8.1 Overview
The TPS22941/2/3/4/5 load switches are 5.5V, current limited load switches in a SC-70 package. The devices
contain a 0.4-Ω current-limited P-channel MOSFET that can operate over an input voltage range of 1.62 V to 5.5
V.
When the switch current reaches the maximum limit, the TPS22941/2/3/4/5 operates in a constant-current mode
to prohibit excessive currents from causing damage. TPS22941/3 has a current limit of 40 mA and TPS22942/4/5
has a current limit of 100 mA.
For the TPS22941/2/5, if the constant current condition still persists after 10ms, these parts shut off the switch
and pull the fault signal pin (OC) low. The TPS22941/2/5 have an auto-restart feature that turns the switch on
again after 80 ms if the ON pin is still active. A current limit condition on the TPS22943 and on the TPS22944
immediately pull the fault signal pin low (OC pin) and the part remains in the constant-current mode until the
switch current falls below the current limit.
8.2 Functional Block Diagram
VIN
5
UVLO
ON
4
Control
Logic
Current
Limit
1
Thermal
Shutdown
VOUT
3
OC
2
GND
8.3 Feature Description
8.3.1 Fault Reporting
When an overcurrent, input undervoltage, or overtemperature condition is detected, OC is set active low to signal
the fault mode. OC is an open-drain MOSFET and requires a pullup resistor between VIN and OC. During
shutdown, the pulldown on OC is disabled, reducing current draw from the supply.
8.3.2 Current Limiting
When the switch current reaches the maximum limit, the TPS22921/2/3/4/5 operates in a constant-current mode
to prohibit excessive currents from causing damage. TPS22921/3 has a current limit of 40 mA and TPS22922/4/5
has a current limit of 100 mA. A current limit condition immediately pulls the fault signal pin low (OC pin), and the
part remains in the constant-current mode until the switch current falls below the current limit.
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Feature Description (continued)
8.3.3 Thermal Shutdown
Thermal shutdown protects the part from internally or externally generated excessive temperatures. During an
overtemperature condition the switch is turned off. The switch automatically turns on again if the temperature of
the die drops below the threshold temperature.
8.4 Device Functional Modes
When the ON pin is actively pulled high and no fault conditions are present, the switch will be turned on,
connecting VIN to VOUT. When the ON pin is actively pulled low regardless of the fault condition, the switch will
be turned off.
In the event that the current limit is exceeded, the device will operate in a constant-current mode and pull the OC
pin low until the fault condition is removed. If the condition persists after the current limit blanking time, the device
will automatically turn off.
During thermal shutdown conditions, the switch will automatically turn off and will turn back on again if the
temperature of the die drops below the threshold temperature.
10
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SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
9 Application and Implementation
This section will highlight some of the design considerations when implementing this device in various
applications.
9.1 Application Information
9.1.1 On/Off Control
The ON pin controls the state of the switch. Activating ON continuously holds the switch in the on state as long
as there is no fault. An undervoltage lockout or thermal shutdown event will override the ON pin control and turn
off the switch. ON is active high and has a low threshold, making it capable of interfacing with low-voltage
signals.
9.1.2 Undervoltage Lockout
The undervoltage lockout turns off the switch if the input voltage drops below the undervoltage lockout threshold.
With the ON pin active, the input voltage rising above the undervoltage lockout threshold causes a controlled
turn-on of the switch, which limits current overshoots.
9.1.3 Reverse Voltage
If the voltage at the VOUT pin is larger than the VIN pin, large currents may flow and can cause permanent
damage to the device. TPS22941/2/3/4/5 is designed to control current flow only from VIN to VOUT.
9.1.4 Input Capacitor
To limit the voltage drop on the input supply caused by transient in-rush currents when the switch turns on into a
discharged load capacitor or a short-circuit, a capacitor needs to be placed between VIN and GND. A 1-μF
ceramic capacitor, CIN, placed close to the pins is usually sufficient. Higher values of CIN can be used to further
reduce the voltage drop.
9.1.5 Output Capacitor
A 0.1-μF capacitor, COUT, should be placed between VOUT and GND. This capacitor will prevent parasitic board
inductances from forcing VOUT below GND when the switch turns off. For the TPS22941/2/3/4/5, the total output
capacitance needs to be kept below a maximum value, COUT(MAX), to prevent the part from registering an overcurrent condition and turning-off the switch.
Due to the integrated body diode in the PMOS switch, a CIN greater than COUT is highly recommended. A COUT
greater than CIN can cause VOUT to exceed VIN when the system supply is removed. This could result in current
flow through the body diode from VOUT to VIN.
9.2 Typical Application
VOUT
VIN
100 kW
On
5.5-V
Battery
ON
10 µF
Off
OC
GND
0.1 µF
500 W
Figure 19. Typical Application Circuit, Active-High Enabled Device
(TPS22943, TPS22944 and TPS22945 Only)
Copyright © 2008–2014, Texas Instruments Incorporated
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www.ti.com
Typical Application (continued)
9.2.1 Design Requirements
For this design example, use the following as the input parameters:
DESIGN PARAMETER
EXAMPLE VALUE
VIN
5.0 V
Load Current
50mA
9.2.2 Detailed Design Procedure
To begin the design process, the designer needs to know the following:
• VIN voltage
• Load current
9.2.2.1 VIN to VOUT Voltage Drop
The VIN to VOUT voltage drop in the device is determined by the RON of the device and the load current. The
RON of the device depends upon the VIN condition of the device. Refer to the RON specification of the device in
the Electrical Characteristics table of this datasheet.
Once the RON of the device is determined based upon the VIN conditions, use Equation 1 to calculate the VIN to
VOUT voltage drop:
∆V = ILOAD × RON
where:
•
•
•
ΔV = voltage drop from VIN to VOUT
ILOAD = load current
RON = ON-resistance of the device for a specific VIN
(1)
9.2.2.2 Maximum Output Capacitance
When designing this device, it is important to ensure the inrush current of the output capacitance does not cause
the device to exceed the current limiting time beyond the blanking time. The maximum output capacitance can be
determined from Equation 2 :
ILM(MAX) ´ tBLANK(MIN)
COUT =
VIN
where:
•
•
•
•
12
COUT = output capacitance
ILIM(MAX) = maximum current limit
tBLANK(MIN) = minimum blanking time
VIN = input voltage
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(2)
Copyright © 2008–2014, Texas Instruments Incorporated
Product Folder Links: TPS22941 TPS22942 TPS22943 TPS22944 TPS22945
TPS22941, TPS22942, TPS22943, TPS22944, TPS22945
www.ti.com
SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
9.2.2.3 Power Dissipation
During normal operation as a switch, the power dissipation is small and has little effect on the operating
temperature of the part. The parts with the higher current limits will dissipate the most power and that will only
be,
PD = (ILIM)2 × rON
(3)
If the part goes into current limit the maximum power dissipation will occur when the output is shorted to ground.
For TPS22941/2/5, the power dissipation scales by the auto-restart time (tRESTART) and the overcurrent blanking
time (tBLANK) so that the maximum power dissipated is:
tBLANK
PD(MAX) = (
) ´ VIN(MAX) ´ ILIM(MAX)
tRESTART + tBLANK
(4)
When using the TPS22943 and TPS22944, a short on the output causes the part to operate in a constant current
state, dissipating a worst-case power as calculated above until the thermal shutdown activates. It then cycles in
and out of thermal shutdown so long as the ON pin is active and the short is present.
9.2.2.4 Application Curves
VDRV
2 V/DIV
VDRV
2 V/DIV
VOUT
2 V/DIV
VOUT
2 V/DIV
IOUT
100 mA/DIV
IOUT
100 mA/DIV
VOC
2 V/DIV
VOC
2 V/DIV
2 ms/DIV
20 ms/DIV
VDRV signal forces the device to go into over-current mode.
Figure 20. tBLANK Response
CL = 0.1 µF
RL = 500 Ω
Figure 22. tON Response
Copyright © 2008–2014, Texas Instruments Incorporated
VDRV signal forces the device to go into over-current mode.
Figure 21. tRESTART Response
VIN = 3.3 V
CL = 0.1 µF
RL = 500 Ω
VIN = 3.3 V
Figure 23. tON Response
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TPS22941, TPS22942, TPS22943, TPS22944, TPS22945
SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
CIN = 10 µF
www.ti.com
COUT = 1 µF
CIN = 10 µF
Figure 24. Short-Circuit Response Time (Output Shorted to
Ground)
CIN = 10 µF
COUT = 1 µF
Figure 25. Short-Circuit Response Time (Switch Powerup
to Hard Short)
COUT = 1 µF
Figure 26. Current Limit Response Time
14
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Copyright © 2008–2014, Texas Instruments Incorporated
Product Folder Links: TPS22941 TPS22942 TPS22943 TPS22944 TPS22945
TPS22941, TPS22942, TPS22943, TPS22944, TPS22945
www.ti.com
SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
10 Power Supply Recommendations
The device is designed to operate from a VIN range of 1.62-V to 5.5-V. This supply must be well regulated and
placed as close to the device terminal as possible with the recommended 1µF bypass capacitor. If the supply is
located more than a few inches from the device terminals, additional bulk capacitance may be required in
addition to the ceramic bypass capacitors. If additional bulk capacitance is required, an electrolytic, tantalum, or
ceramic capacitor of 10-µF may be sufficient.
11 Layout
11.1 Layout Guidelines
•
•
•
•
•
For best performance, all traces should be as short as possible.
To be most effective, the input and output capacitors should be placed close to the device to minimize the
effects that parasitic trace inductances may have on normal and short-circuit operation.
The VIN terminal should be bypassed to grond with low ESR ceramic bypass capacitors. The typical
recommended bypass capacitance is 1-µF ceramic with X5R or X7R dielectric. This capacitor should be
placed as close to the device terminals as possible.
The VOUT terminal should be bypassed to grond with low ESR ceramic bypass capacitors. The typical
recommended bypass capacitance is one-tenth of the VIN bypass capacitor of X5R or X7R dielectric. This
capacitor should be placed as close to the device terminals as possible.
Using wide traces for VIN, VOUT, and GND will help minimize parasitic electrical effects along with minimizing
the case to ambient thermal impedance.
11.2 Layout Example
VOUT
Plane
VIN
Plane
VIN
VOUT
VIN Bypass
Capacitor
VOUT Bypass
Capacitor
Gnd
Via
GND
Gnd
Via
To GPIO control
ON
Copyright © 2008–2014, Texas Instruments Incorporated
To
Microcontroller
OC
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SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
www.ti.com
11.3 Thermal Considerations
The maximum junction temperature will be internally limited by the thermal shutdown (TSD). To calculate the
maximum allowable dissipation, PD(MAX) for a given ambient temperature, use Equation 5.
TSD - TA
PD(MAX) =
qJA
where:
•
•
•
•
16
PD(MAX) = maximum allowable power dissipation
TSD = thermal shutdown threshold (140 °C typical)
TA = ambient temperature of the device
θJA = junction to air thermal impedance. See the section. This parameter is highly dependent upon board
layout.
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(5)
Copyright © 2008–2014, Texas Instruments Incorporated
Product Folder Links: TPS22941 TPS22942 TPS22943 TPS22944 TPS22945
TPS22941, TPS22942, TPS22943, TPS22944, TPS22945
www.ti.com
SLVS832D – NOVEMBER 2008 – REVISED JULY 2014
12 Device and Documentation Support
12.1 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 1. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
TPS22941
Click here
Click here
Click here
Click here
Click here
TPS22942
Click here
Click here
Click here
Click here
Click here
TPS22943
Click here
Click here
Click here
Click here
Click here
TPS22944
Click here
Click here
Click here
Click here
Click here
TPS22945
Click here
Click here
Click here
Click here
Click here
12.2 Trademarks
All trademarks are the property of their respective owners.
12.3 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.
12.4 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
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.
Copyright © 2008–2014, Texas Instruments Incorporated
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17
PACKAGE OPTION ADDENDUM
www.ti.com
13-Aug-2021
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)
TPS22941DCKR
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
4AN
TPS22942DCKR
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
(4BJ, 4BN)
TPS22942DCKRG4
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
(4BJ, 4BN)
TPS22943DCKR
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
4CN
TPS22944DCKR
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
4DN
TPS22945DCKR
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
(4EJ, 4EN)
TPS22945DCKRG4
ACTIVE
SC70
DCK
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
(4EJ, 4EN)
(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
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