ALED7709 datasheet(5/63 Pages) STMICROELECTRONICS

5 / 63 page

Pin #

Symbol

Function

FSW

Switching frequency setting. A resistor between this pin and SGND sets the desired

switching frequency. This pin is also the synchronization input using a direct pulse signal.

SLOPE

Control loop compensation slope setting. A resistor between this pin and SGND sets the

proper amount of compensation slope for the control loop of the DC-DC converter.

COMP

DC-DC converter loop compensation. A proper RC filter must be connected between this

pin and SGND for loop compensation.

VFB

Output voltage feedback input by an external resistor ladder.

PGND

Power ground connection. External components of the DC-DC converter must refer to this

ground pin.

GATE

External power NMOS switch gate driver output.

LDO5

5.1 V linear regulator supplies the external power NMOS switch gate driver.

Connect a 1 µF bypass capacitor between this pin and PGND as close as possible to the

device.

PSW

Switch gate control pin for optional external PMOS for system input protection. Can be left

floating or connected through a resistor to ICSN pin if unused.

ICSN

Input and external power NMOS switch current sensing, negative terminal. Connect this

pin to the negative terminal of the input current sensing resistor. The differential voltage

between the VIN and ICSN pins is used to sense the current flowing in the DC-DC

converter stage and to set the threshold for the overcurrent protection.

VIN

Supply voltage input. Place a 1 µF bypass capacitor to ground as close as possible to the

device.

TPAD

Thermal pad. Connect to a suitable (JESD51-7) copper area (it could or not be electrically

connected to ground) for power dissipation improvement.

ALED7709

Pin configuration

DS14214 - Rev 1

page 5/63

ALED7709 Datasheet(PDF) 5 Page - STMicroelectronics