HV9963 Datasheet, PDF (1/12 Pages) Supertex, Inc – Closed Loop LED Driver with Enhanced PWM Dimming

HV9963
Closed Loop LED Driver with Enhanced PWM Dimming
Features
► Switch mode controller for single switch converters
● Buck
● Boost
● Buck-boost and SEPIC
► High output current accuracy
► High PWM dimming ratio (>5000:1)
► Internal 40V linear regulator
► Internal ±2% voltage reference
► Constant frequency operation with sync capability
► Programmable soft start
► 10V GATE drivers
► Hiccup mode protection for both short circuit and
open circuit conditions
Applications
► RGB or white LED backlighting
► Battery powered LED lamps
► Other DC/DC LED drivers
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
D2 (optional)
C_IN
C_PVDD
D1
Q1
C_SC
R_CS
R_OVP1
C_O
R_OVP2
VIN ^{PVDD GT CS}
OVP _FLT
GND
HV9963
PWMD
HCP SYNC SS COMP RT
FB
IREF
AVDD
C_HCP
C_SS
C_C
R_T
R_REF1
C_AVDD
Q2
R_S
R_REF2
● 1235 Bordeaux Drive, Sunnyvale, CA 94089 ● Tel: [phone] ● www.supertex.com