HV9963

Features

open circuit conditions

Applications

General Description

The HV9963 is a current mode control LED driver IC designed

to control single switch PWM converters (buck, boost,

buck-boost or SEPIC) in a constant frequency mode. The

controller uses a peak current-mode control scheme (with

programmable slope compensation) and includes an internal

transconductance amplifier to accurately control the output

current over all line and load conditions. Multiple HV9963s

can be synchronized to each other or to an external clock

using the SYNC pin. The IC also provides a disconnect switch

gate drive output, which can be used to disconnect the LEDs

in case of a fault condition using an external disconnect

FET. The 10V external FET drivers allow the use of standard

level FETs. The low voltage 5.0V AVDD is used to power the

internal logic and also acts as a reference voltage to set the

current level.

The HV9963 includes an enhanced PWM dimming logic (patent

pending) that enables very high PWM dimming ratios.

HV9963 also provides a TTL compatible, low-frequency PWM

dimming input that can accept an external control signal with

a duty ratio of 0-100% and a frequency of up to a few tens of

kilohertz.

Typical Application Circuit

Closed Loop LED Driver with Enhanced PWM Dimming

GT

CS

PVDD

VIN

GND

OVP

IREF

FB

FLT

AVDD

SS

HCP

PWMD

RT

SYNC

COMP

HV9963

Q1

R

CS

D1

C

O

C

IN

Q2

R

S

R

REF1

R

REF2

C

SS

C

C

C

AVDD

C

HCP

R

T

C

PVDD

C

SC

D2 (optional)

R

OVP1

R

OVP2