LM5033SDX National Semiconductor, LM5033SDX Datasheet - Page 2

• Manufacturer Part Number: LM5033SDX
• Description: 100V Push-Pull Voltage Mode PWM Controller
• Manufacturer: National Semiconductor

www.national.com
PIN
Pin Description
10
1
2
3
4
5
6
7
8
9
R
T
NAME
COMP
OUT1
OUT2
GND
VCC
/ SYNC Oscillator timing resistor pin and synchronization
REF
Vin
CS
SS
Input Voltage
2.5V precision reference output
PWM Input
9.6V output from the internal high voltage series
pass regulator
Gate Driver Output #1
Gate Driver Output #2
Ground pin for all internal circuitry
Current sense input
input
Softstart pin
DESCRIPTION
2
Input to the start-up regulator. Input range is 15V to
90V, with transient capability to 100V .
Sink only, requires an external pull-up resistor. This
can be used as a reference for external circuitry.
Feedback to the PWM comparator’s inverting input,
through a 3:1 divider. The output duty cycle increases
as this pin’s voltage increases. Internally there is a
5kΩ pullup to +5.2V.
An external voltage (10V - 15V) can be applied to this
pin to shutdown the internal regulator, thereby
reducing internal dissipation. An internal diode
connects Vcc to Vin.
Alternating output gate driver, which can source and
sink 1.5A.
Alternating output gate driver, which can source and
sink 1.5A.
Connections to external ground must be done with
care for optimum performance. See the Functional
Description and Applications Section for more
information.
Current sense input for the current limit detection. If
CS exceeds 0.5V the outputs are disabled and the
softstart pin is discharged to ground.
An external resistor to ground sets the oscillator
frequency. This pin will also accept ac-coupled
synchronization pulses from an external source.
An internal 10µA current source and an external
capacitor set the soft-start timing. This pin can be
externally pulled to below 0.5V to disable the output
drivers.
APPLICATION INFORMATION