MAX5077 Datasheet, PDF (1/9 Pages) Maxim Integrated Products – Push-Pull FET Driver with Integrated Oscillator and Programmable Clock Output

19-3663; Rev 0; 5/05
Push-Pull FET Driver with Integrated Oscillator
and Programmable Clock Output
General Description
The MAX5077 is a +4.5V to +15V push-pull, current-fed
topology driver subsystem with an integrated oscillator
used in telecom module power supplies. The device
drives two MOSFETs connected to a center-tapped
transformer primary providing secondary-side, isolated,
negative or positive voltages. The MAX5077 features a
programmable accurate integrated oscillator with a
synchronizing clock output to synchronize an external
PWM regulator. A single external resistor programs the
internal oscillator frequency from 50kHz to 1.5MHz.
The MAX5077 incorporates dual MOSFET drivers with
±3A peak drive currents and 50% duty cycle. The
MOSFET drivers generate complementary signals to
drive external ground-referenced n-channel MOSFETs.
The MAX5077 clock output frequency is programmable
by logic inputs to set the clock output to 1x, 2x, or 4x
the MOSFET’s driver frequency.
The MAX5077 is available in a 14-pin exposed pad
TSSOP package and is specified over the -40°C to
+125°C operating temperature range.
Applications
Current-Fed Power Supplies
Power-Supply Building Subsystems
Push-Pull Driver Subsystems
V_IN
V_IN
DRVH
Features
o Dedicated Current-Fed, Push-Pull Driver
Subsystem
o Oscillator Frequency Programmable from 50kHz
to 1.5MHz
o Single +4.5V to +15V Supply Voltage Range
o ±3A Peak Gate-Drive Current
o 1mA Operating Current at 250kHz with No
Capacitive Load
o Selectable Synchronizing Clock Frequency for a
Preceding PWM Stage
o Thermally Enhanced 14-Pin TSSOP
o -40°C to +125°C Operating Temperature Range
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
PKG
CODE
MAX5077AUD -40°C to +125°C 14 TSSOP-EP* U14E-3
*EP = Exposed paddle.
Pin Configuration appears at end of data sheet.
Typical Operating Circuit
V_OUT
SYNCIN
PWM
CONTROLLER
DRVL
GND
GND
CLK
V_CC
MAX5077
V_CC
NDRV2
SEL1
I.C.
NDRV1
RT
SEL2
AGND DGND PGND
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