JAJSM84B december 2022 – july 2023 LM74900-Q1 , LM74910-Q1
PRODUCTION DATA
PIN | TYPE(1) | DESCRIPTION | |
---|---|---|---|
NAME | NO. | ||
DGATE | 1 | O | Diode controller gate drive output. Connect to the GATE of the external MOSFET. |
A | 2 | I | Anode of the ideal diode. Connect to the source of the external MOSFET. |
SW | 3 | I | Voltage sensing disconnect switch terminal. VSNS and SW are internally connected through a switch. Use SW as the top connection of the battery sensing or OV resistor ladder network. When EN is pulled low, the switch is OFF disconnecting the resistor ladder from the battery line thereby cutting off the leakage current. If the internal disconnect switch between VSNS and SW is not used then short them together and connect to VS pin. |
UVLO | 4 | I | Adjustable undervoltage threshold input. Connect a resistor ladder across SW 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. |
OV | 5 | I | Adjustable overvoltage threshold input. Connect a resistor ladder across SW 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. |
EN | 6 | I | EN input. Connect to VS pin for always ON operation. Can be driven externally from a microcontroller I/O. Pulling it low below V(ENF) makes the device enter into low Iq shutdown mode. |
SLEEP | 7 | I | Active low SLEEP mode input. Can be driven from the microcontroller. When pulled low device enters into low power state with charge pump and gate drive turned off. Internal bypass switch provides output voltage with limited current capacity. |
NC | 8 | — | No connect. |
TMR | 9 | I | 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 RSNS. A resistor from this pin to GND converts current to proportional voltage. If unused, leave it floating. |
ILIM | 11 | I | 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 UVLO, OV, OCP, or SCP 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 FET. |
OUT | 15 | I | Connect to the output rail (external MOSFET source). |
SLEEP_OV | 16 | I | SLEEP mode overvoltage protection pin. Connect this pin to VS for overvoltage cut-off functionality. Connect to OUT for overvoltage clamp functionality. |
NC | 17 | — | No connect. |
ISCP | 18 | I | Short circuit detection threshold setting. Leave ISCP floating if short circuit protection is not desired. When ISCP is connected to CS+, device sets an internal fix threshold of 20 mV. |
CS– | 19 | I | Current sense negative input. |
CS+ | 20 | I | Current sense positive input. Connect a TBD resistor across CS+ to the external current sense resistor. |
NC | 21 | — | No connect. |
VS | 22 | P | Input power supply to the IC. Connect VS to middle point of the common drain back to back MOSFET configuration. Connect a 100-nF capacitor across VS and GND pins. |
CAP | 23 | O | Charge pump output. Connect a 100-nF capacitor across CAP and VS pins. |
C | 24 | I | Cathode of the ideal diode. Connect to the drain of the external MOSFET. |
RTN | Thermal Pad | — | Leave exposed pad floating. Do not connect to GND plane. |