The TPS22946 is an ultralow power load switch that provides protection to systems and loads in high-current conditions. The device contains a 300-mΩ current-limited P-channel MOSFET that can operate over an input voltage range of 1.62 V to 5.5 V. The switch is controlled by an on/off input (ON), which can interface directly with low-voltage control signals. The TPS22946 includes thermal shutdown protection that prevents damage to the device when a continuous over-current condition causes excessive heating by turning off the switch.
When the switch current reaches the maximum limit, the TPS22946 operates in a constant-current mode to prohibit excessive currents from causing damage. The current limit can be selected using the CL input: a high CL input sets the current limit to 155 mA, a low CL input sets the current limit to 70 mA, and a floating CL input sets the current limit to 30 mA.
If the constant current condition persists after 10 ms, the switch is turned off and the fault signal pin (OC) is pulled low. The TPS22946 has an auto-restart feature which turns the switch on again after 70 ms if the ON pin is still active. If the TPS22946 remains in an over-current condition for 5 seconds, the device shuts off until it is turned on again by setting the ON control signal off and then on.
If the device is used to protect an LDO, the inrush current required by the LDO at startup can, in some cases, exceed the current limit and initiate a blanking (current limiting) condition. The TPS22946 provides allowance for this scenario during startup of the LDO by temporarily increasing the current limit to 435 mA for 8 ms after the load switch is enabled.
The TPS22946 is available in space-saving 6-pin DSBGA (YZP) package. The device is characterized for operation over the free-air temperature range of –40°C to 85°C.
PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|---|---|
TPS22946 | DSBGA (6) | 0.90 mm × 1.40 mm |
Changes from A Revision (February 2010) to B Revision
C | ON | OC |
B | CL | GND |
A | VIN | VOUT |
2 | 1 |
PIN | I/O | DESCRIPTION | |
---|---|---|---|
NO. | NAME | ||
A1 | VOUT | O | Output of the power switch |
A2 | VIN | I | Supply. Input to the power switch and the supply voltage for the device |
B1 | GND | – | Ground |
B2 | CL | I | Current limit selection. CL high is 155-mA current limit, CL low is 70-mA current limit, and CL floating is 30-mA current limit. |
C1 | OC | O | Overcurrent output flag. Active-low open-drain output that indicates an overcurrent, supply undervoltage, or overtemperature state. |
C2 | ON | I | On/off control input |
MIN | MAX | UNIT | |||
---|---|---|---|---|---|
VI | Input voltage | VIN, VOUT, ON, CL | –0.3 | 6 | V |
TJ | Operating junction temperature | –40 | 125 | °C | |
Tstg | Storage temperature | –65 | 150 | °C |
VALUE | UNIT | |||
---|---|---|---|---|
V(ESD) | Electrostatic discharge | Human body model (HBM), per JEDEC specification JESD22 (A114-B, Class II)(1) | ±6000 | V |
Charged-device model (CDM), per JEDEC specification JESD22-C101(2) | ±2000 |
MIN | MAX | UNIT | |||
---|---|---|---|---|---|
VIN | Input voltage | 1.62 | 5.5 | V | |
VON | ON pin voltage | 0 | 5.5 | V | |
VCL | CL pin voltage | 0 | VIN | V | |
VOUT | OUT pin voltage | 0 | VIN | V | |
TA | Ambient free-air temperature | –40 | 85 | °C | |
tCLSET | CL pin setting time | 8 | ms | ||
CIN | Input capacitor | 1(1) | μF | ||
VIH | ON high-level input voltage | VIN = 1.8 V | 1.1 | 5.5 | V |
VIN = 2.5 V | 1.2 | 5.5 | |||
VIN = 3.3 V | 1.3 | 5.5 | |||
VIN = 5.5 V | 1.4 | 5.5 | |||
VIL | ON low-level input voltage | VIN = 1.8 V | 0.4 | V | |
VIN = 2.5 V | 0.4 | ||||
VIN = 3.3 V | 0.5 | ||||
VIN = 5.5 V | 0.6 | ||||
VIH | CL low-level input voltage | VIN = 1.62 V to 5.5 V, IIH = 55 μA | 0.7 VIN | VIN | V |
VIL | CL high-level input voltage | VIN = 1.62 V to 5.5 V, IIL = 55 μA | GND | 0.3 VIN | V |
THERMAL METRIC(1) | TPS22946 | UNIT | |
---|---|---|---|
YZP (DSBGA) | |||
6 PINS | |||
RθJA | Junction-to-ambient thermal resistance | 131 | °C/W |
RθJC(top) | Junction-to-case (top) thermal resistance | 1.3 | |
RθJB | Junction-to-board thermal resistance | 22.6 | |
ψJT | Junction-to-top characterization parameter | 5.2 | |
ψJB | Junction-to-board characterization parameter | 22.6 |
PARAMETER | TEST CONDITIONS | TA(1) | MIN | TYP | MAX | UNIT | ||
---|---|---|---|---|---|---|---|---|
IIN | Average quiescent current | IOUT = 0 mA, VIN = 4.5 V to 5.5 V | Full range | 1.5 | 5 | μA | ||
IOUT = 0 mA, VIN = 3.0 V to 3.6 V | 1.3 | 4 | ||||||
IOUT = 0 mA, VIN = 1.62 V to 1.98 V | 1 | 3 | ||||||
IIN(OFF) | OFF state supply current | VON = 0 V | VIN = 3.6 V, VOUT open | Full range | 0.1 | 1 | μA | |
IOUT(LEAKAGE) | OFF state switch current | VON = 0 V | VIN = 3.6 V, VOUT short to GND |
Full range | 0.1 | 1.1 | μA | |
rON | ON-state resistance | IOUT = –100 mA | VIN = 5.5 V | 25°C | 0.3 | 0.4 | Ω | |
Full range | 0.45 | |||||||
VIN = 3.3 V | 25°C | 0.4 | 0.5 | |||||
Full range | 0.55 | |||||||
VIN = 2.5 V | 25°C | 0.5 | 0.6 | |||||
Full range | 0.65 | |||||||
VIN = 1.8 V | 25°C | 0.6 | 0.8 | |||||
Full range | 0.85 | |||||||
VIN = 1.62 V | 25°C | 0.7 | 0.9 | |||||
Full range | 1 | |||||||
ION | ON input leakage current | VON = VIN or GND | Full range | 1 | μA | |||
ILIM | Current limit | VIN = 1.8 V, VOUT = 1.5 V, CL = GND | Full range | 70 | 85 | 120 | mA | |
VIN = 3.3 V, VOUT = 3.0 V, CL = GND | Full range | 60 | 80 | 115 | ||||
VIN = 1.8 V, VOUT = 1.5 V, CL = VIN | Full range | 155 | 175 | 235 | ||||
VIN = 3.3 V, VOUT = 3.0 V, CL = VIN | Full range | 135 | 165 | 230 | ||||
VIN = 1.8 V, VOUT = 1.5 V, CL floating | Full range | 30 | 45 | 60 | ||||
VIN = 3.3 V, VOUT = 3.0 V, CL floating | Full range | 28 | 40 | 60 | ||||
Ilimit_inrush | Inrush current limit | Rl = 1 Ω, VIN = 3.3 V, VOUT = 2.3 V | Full range | 375 | 435 | 685 | mA | |
Thermal shutdown(2) | Shutdown threshold | Full range | 135 | °C | ||||
Return from shutdown | 125 | |||||||
Hysteresis | 10 | |||||||
VOL | OC output logic low voltage | VIN = 5 V, ISINK = 10 mA | Full range | 0.1 | 0.2 | V | ||
VIN = 1.8 V, ISINK = 10 mA | 0.1 | 0.3 | ||||||
IOH | OC output high leakage current | VIN = 5 V, Switch ON | Full range | 1 | μA |
PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNIT | |
---|---|---|---|---|---|---|
tPWRON | Power-on time | RL = 50 Ω, CL = 1 μF | 192 | μs | ||
tPWROFF | Power-off time | RL = 50 Ω, CL = 1 μF | 0.55 | μs | ||
tON | Turnon time | RL = 50 Ω, CL = 1 μF | 125 | μs | ||
tOFF | Turnoff time | RL = 50 Ω, CL = 1 μF | 115 | μs | ||
tR | VOUT rise time | RL = 50 Ω, CL = 1 μF | 35 | μs | ||
tF | VOUT fall time | RL = 50 Ω, CL = 1 μF | 120 | μs | ||
tBLANK | Overcurrent blanking time | 7 | 10 | 15 | ms | |
tRSTART | Auto-restart time | 50 | 70 | 95 | ms | |
tTIMEOUT | Overcurrent detection time-out(3) | VIN = VON = 3.3 V, hard short(2) | 6000 | ms | ||
tOVRTMP | Overtemperature detection maximum response time | 7.7 | ms | |||
tMODOC | Moderate overcurrent detection maximum response time | VIN = VON = 1.8 V, Moderate over-current condition(1) | 63.5 | ms | ||
VIN = VON = 3.3 V, Moderate overcurrent condition(1) | 65.5 | |||||
tHARDSHORT | Hard-short detection maximum response time | VIN = VON = 1.8 V, hard short(2) | 270 | μs | ||
VIN = VON = 3.3 V, hard short(2) | 295 |