HV9919 Supertex, Inc., HV9919 Datasheet - Page 6

• Manufacturer Part Number: HV9919
• Manufacturer: Supertex, Inc.

connecting high-current ground returns, the input bypass
capacitor ground lead, and the output filter ground lead to
a single point (star ground configuration). The fast di/dt loop
is formed by the input capacitor C
and the MOSFET. To minimize noise interaction, this loop
area should be as small as possible. Place R
Pin Description
Pin #
TAB
1
2
3
4
5
6
7
8
RAMP
GATE
ADIM
GND
GND
VDD
DIM
VIN
Pin
CS
Description
Current sense input. Senses LED string current.
Input voltage 4.5 to 40V DC.
Analog PWM dimming ramp output.
Analog 0~2.0V signal input for analog control of PWM dimming.
PWM signal input.
Internally regulated supply voltage. Connect a capacitor from VDD to ground.
Device ground.
Drives gate of external MOSFET.
Must be wired to pin 7 on PCB.
IN
, the free-wheeling diode
SENSE
as close
6
as possible to the input filter and VIN. For better noise immu-
nity, a Kelvin connection is strongly recommended between
CS and R
ode, the sense resistor, and the input bypass capacitor is
essential. Connect the exposed tab of the IC to a large-area
ground plane for improved power dissipation.
SENSE
. A star connection including the diode’s an-
HV9919