ZHCSQK6 May 2022 TPS92643-Q1
PRODUCTION DATA
Table 7-1 summarizes the device behavior under fault conditions.
FAULT | DETECTION | DESCRIPTION | ||
---|---|---|---|---|
Thermal protection | TJ > 175°C | The thermal protection is activated in the event the maximum MOSFET temperature exceeds the typical value of 175°C. This feature is designed to prevent overheating and damage to the internal switching MOSFETs. | ||
VCC undervoltage lockout | VCC(RISE) < 4.4 V | The device enters the Undervoltage Lockout (UVLO). The switching operation is disabled, the COMP capacitor is discharged. | ||
VCC(FALL) < 4.2 V | ||||
VIN dropout protection | VUDIM < 2.34 V | The device disables error amplifier and disconnects the compensation network for the corresponding channel. Error amplifier is enabled and compensation network is internally connected when the input voltage rises above the dropout rising threshold, VIN(DO,RISE). | ||
VIN undervoltage lockout | VUDIM < 1.12 V | The device disables switching operation for the corresponding channel. Switching is enabled when the input voltage rises above the turn-on threshold, VIN(UVLO,RISE). | ||
BST undervoltage lockout | VBST(RISE) < 3.2 V | The device turns off the high-side MOSFET and turns on the low-side MOSFET for the corresponding channel. Normal switching operation is resumed after the bootstrap voltage exceeds 3.2 V. | ||
VBST(FALL) < 2.93 V | ||||
COMP overvoltage | VCOMP > 3.2 V | The FLT flag is set low to indicate that the COMP voltage exceeded the normal operating range. This condition indicates output open-circuit fault. | ||
Short output | VCSN < 1.5 V | The FLT flag is set low to indicate an output short-circuit condition based on sensed CSN voltage. | ||
High-side switch current limit | IHS > 4.8 A | The device turns off the high-side MOSFET, turns on low-side MOSFET and discharges the COMP capacitor. The device attempts to restart after a delay of 5.5 ms. | ||
Low-side switch current limit | ILS > 3.2 A | The device turns off both high-side and low-side MOSFETs and discharges the COMP capacitor. The device attempts to restart after a delay of 5.5 ms. |
Output open and short circuit faults force the FLT pin low when biased through an external resistor and connected to a 5-V supply. The FLT output can be used in conjunction with a microcontroller or system basis chip (SBC) as an interrupt and aid in fault diagnostics.