HV9910C

DS20005323A-page 6

 2014 Microchip Technology Inc.

2.0

PIN DESCRIPTION

The descriptions of the pins are listed in Table 2-1.

TABLE 2-1:

PIN DESCRIPTION

Pin #

Function

Description

8-Lead SOIC 16-Lead SOIC

1

1

VIN

Input of an 15 - 450V linear regulator.

2

4

CS

Current sense pin used to sense the FET current by means of an

external sense resistor. When this pin exceeds the lower of either

the internal 250mV or the voltage at the LD pin, the GATE output

goes low.

3

5

GND

Ground return for all internal circuitry. Must be electrically con-

nected to the power ground.

4

8

GATE

Output GATE driver for an external N-channel power MOSFET.

5

9

PWMD

TTL-compatible, PWM-dimming input of the IC. When this pin is

pulled to GND or left open, the GATE driver is turned off. When the

pin is pulled high, the GATE driver operates normally.

6

12

VDD

Power supply pin for all internal circuits. It must be bypassed with a

low ESR capacitor to GND (≥0.1μF).

7

13

LD

Linear-dimming input and sets the current sense threshold as long

as the voltage at the pin is less than 250mV (typ).

8

14

RT

Sets the oscillator frequency. When a resistor is connected

between RT and GND, the HV9910C operates in constant fre-

quency mode. When the resistor is connected between RT and

GATE, the IC operates in constant off-time mode.

-

2, 3, 6, 7, 10,

11, 15, 16

NC

No connection