RS6513

V1.0

3

August 2013

PIN ASSIGNMENTS

SOP-8

PIN DESCRIPTION

Pin Name

Description

Pin No.

FB

Feedback Pin

1

EN

POWER OFF Pin:

H: Normal operation (Step-down operation)

L: Step-down operation stopped (All circuits deactivated)

2

OCSET

Add an external resistor to set max output current

3

VCC

Power Supply Pin

4

OUTPUT

Switch Pin. Connect external inductor/diode here. Minimize trace area at this pin to reduce

EMI

5, 6

VSS

Ground Pin

7, 8

FUNCTION DESCRIPTION

PWM CONTROL

The RS6513 consists of DC/DC converters that employ a pulse-width modulation (PWM) system. In converters of the

RS6513, the pulse width varies in a range from 0 to 100%, according to the load current. The ripple voltage produced by

the switching can easily be removed through a filter because the switching frequency remains constant. Therefore, these

converters provide a low-ripple power over broad ranges of input voltage and load current.

UNDER VOLTAGE LOCKOUT

The under voltage lockout circuit of the RS6513 assures that the high-side MOSFET driver outputs remain in the off state

whenever the supply voltage drops below 3.3V. Normal operation resumes once VCC rises above 3.5V.

RDS(ON) CURRENT LIMITING

The current limit threshold is setting by the external resistor connecting from VCC supply to OCSET. The internal 100uA

sink current crossing the resistor sets the voltage at the pin of OCSET. When the PWM voltage is less than the voltage at

OCSET, an over-current condition is triggered.

See above formula for setting the current limit value.