Dual Bootstrapped, High Voltage MOSFET
Driver with Output Disable
ADP3419
FEATURES
SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM
All-in-one synchronous buck driver
One PWM signal generates both drives
Anticross-conduction protection circuitry
Output disable function
Crowbar control
Synchronous override control
Undervoltage lockout
VCC
5
BST
10
1
2
9
8
DRVH
SW
IN
UVLO,
OVERLAP
PROTECTION,
SHUTDOWN
AND
SD
3
4
DRVLSD
CROWBAR
CIRCUITS
APPLICATIONS
6
DRVL
CROWBAR
Mobile computing CPU core power converters
Multiphase desk-note CPU supplies
ADP3419
7
Single-supply synchronous buck converters
Nonsynchronous-to-synchronous drive conversion
GND
Figure 1.
GENERAL DESCRIPTION
The ADP3419 is a dual MOSFET driver optimized for driving
two N-channel switching MOSFETs in nonisolated synchro-
nous buck power converters used to power CPUs in portable
computers. The driver impedances have been chosen to provide
optimum performance in multiphase regulators at up to 25 A
per phase. The high-side driver can be bootstrapped relative to
the switch node of the buck converter and is designed to
accommodate the high voltage slew rate associated with floating
high-side gate drivers.
GENERAL APPLICATION CIRCUIT
5V
VDC
5
VCC
FROM CONTROLLER
1
2
3
IN
10
9
BST
PWM OUTPUT
ADP3419
FROM SYSTEM
ENABLE CONTROL
DRVH
SW
V
SD
OUT
FROM
CONTROLLER
8
6
DRVLSD
The ADP3419 includes an anticross-conduction protection
circuit, undervoltage lockout to hold the switches off until the
driver has sufficient voltage for proper operation, a crowbar
input that turns on the low-side MOSFET independently of the
input signal state, and a low-side MOSFET disable pin to
FROM CONTROLLER
CLAMP OUTPUT
4
CROWBAR DRVL
GND
7
Figure 2.
SD
provide higher efficiency at light loads. The
pin shuts off
both the high-side and the low-side MOSFETs to prevent rapid
output capacitor discharge during system shutdown.
The ADP3419 is specified over the extended commercial
temperature range of 0°C to 100°C and is available in a 10-lead
MSOP package.
Rev. A
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