5 Pin Configuration and Functions

Figure 5-1 VQFN24-Pin RGETransparent Top View

Table 5-1 Pin Functions

PIN		TYPE⁽¹⁾	DESCRIPTION
NAME	LM74930-Q1
NAME	RGE-24 (VQFN)
DGATE	1	O	Diode Controller Gate Drive Output. Connect to the GATE of the external ideal diode MOSFET.
A	2	I	Anode of the ideal diode. Connect to the source of the external ideal diode MOSFET.
SW	3	I	Voltage sensing disconnect switch terminal. A and SW are internally connected through a switch. Use SW as the top connection of the resistor ladder to measure voltage at the common source node. When EN is pulled low, the switch is OFF. If the internal disconnect switch between A and SW is not used then SW pin can be left floating.
UVLO	4	I	Adjustable undervoltage threshold input. Connect a resistor ladder across VIN to UVLO terminal to GND. When the voltage at UVLO goes below the undervoltage cut-off threshold then the HGATE is pulled low turning OFF the HSFET. HGATE turns ON when the sense voltage goes above the UVLO falling threshold. When not used UVLO should be tied to VS or EN pin.
OV	5	I	Adjustable overvoltage threshold input. Connect a resistor ladder across VIN/VOUT to OV terminal. When the voltage at OVP exceeds the overvoltage cut-off threshold then the HGATE is pulled low turning OFF the HSFET. HGATE turns ON when the sense voltage goes below the OVP falling threshold. When not used OV should be tied to ground.
EN	6	I	EN Input. Connect to VS pin for always ON operation. Can be driven externally from a micro controller I/O. Pulling this pin low below V_(ENF) makes the device enter into low Iq shutdown mode.
MODE	7	I	MODE input to disable reverse current blocking function of DGATE. MODE pin can be driven from the microcontroller. When pulled low device disables reverse current blocking feature (DGATE). When not used, MODE pin can be pulled to EN or VS.
N.C	8	—	No Connection. Keep this pin floating.
TMR	9	—	Fault timer input. A capacitor across TMR pin to GND sets the times for fault warning, fault turn-off (FLT), and retry periods. Leave it open for fastest setting. Connect TMR to GND to disable overcurrent protection.
IMON	10	O	Analog current monitor output. This pin sources a scaled down ratio of current through the external current sense resistor R_SENSE. A resistor from this pin to GND converts current to proportional voltage. If unused, leave this pin floating.
ILIM	11	—	Overcurrent detection setting. A resistor across ILIM to GND sets the overcurrent comparator threshold. Connect ILIM to GND if overcurrent protection feature is not desired.
FLT	12	O	Open drain fault output. FLT pin is pulled low in case of undervoltage, overvoltage, overcurrent and short circuit event.
GND	13	G	Connect to the system ground plane
HGATE	14	O	GATE driver output for the HSFET. Connect to the GATE of the external load switch MOSFET.
OUT	15	I	Connect to the common source rail (external load switch MOSFET source)
OVCLAMP	16	I	Connect this pin to OV pin for overvoltage clamp with circuit breaker (timer) functionality. Connect this pin to ground when not used.
N.C	17	—	No Connection. Keep this pin floating.
ISCP	18	I	Short-circuit detection threshold setting. When ISCP is connected to C, device sets an internal fix threshold of 20 mV for output short circuit detection.
CS-	19	I	Current sense negative input.
CS+	20	I	Current sense positive input. Connect a 50-Ω resistor across CS+ to the external current sense resistor.
N.C	21	—	No Connection. Keep this pin floating.
VS	22	P	Input power supply to the IC. Connect a 100-nF capacitor across VS and GND pin.
CAP	23	O	Internal charge pump output. Connect a 100-nF capacitor across CAP and VS pin.
C	24	I	Cathode of the ideal diode. Connect to the drain of the external ideal diode MOSFET.
RTN	Thermal pad	—	Leave exposed pad floating. Do Not connect to GND plane.

(1) I = input, O = output, I/O = input and output, P = power, G = Ground