L6910_05 Datasheet, PDF (1/29 Pages) STMicroelectronics – ADJUSTABLE STEP DOWN CONTROLLER WITH SYNCHRONOUS RECTIFICATION

L6910
L6910A
ADJUSTABLE STEP DOWN CONTROLLER
WITH SYNCHRONOUS RECTIFICATION
1 FEATURES
■ OPERATING SUPPLY VOLTAGE FROM 5V
TO 12V BUSES
■ UP TO 1.3A GATE CURRENT CAPABILITY
■ ADJUSTABLE OUTPUT VOLTAGE
■ N-INVERTING E/A INPUT AVAILABLE
■ 0.9V ±1.5% VOLTAGE REFERENCE
■ VOLTAGE MODE PWM CONTROL
■ VERY FAST LOAD TRANSIENT RESPONSE
■ 0% TO 100% DUTY CYCLE
■ POWER GOOD OUTPUT
■ OVERVOLTAGE PROTECTION
■ HICCUP OVERCURRENT PROTECTION
■ 200kHz INTERNAL OSCILLATOR
■ OSCILLATOR EXTERNALLY ADJUSTABLE
FROM 50kHz TO 1MHz
■ SOFT START AND INHIBIT
■ PACKAGES: SO-16 & HTSSOP16
2 APPLICATIONS
■ SUPPLY FOR MEMORIES AND TERMI-
NATIONS
■ COMPUTER ADD-ON CARDS
■ LOW VOLTAGE DISTRIBUTED DC-DC
■ MAG-AMP REPLACEMENT
3 DESCRIPTION
The device is a pwm controller for high performance
Figure 2. Block Diagram
PGOOD
VREF
SS
OSC
RT
EAREF
VCC OCSET
MONITOR
PROTECTION
& REF
OSC
E/A
+
-
PWM
-
+
May 2005
D03IN1509
COMP
Figure 1. Packages
SO-16 (Narrow)
HTSSOP16 (Exposed Pad)
Table 1. Order Codes
Part Number
Package
L6910
L6910TR
L6910A
SO-16
SO-16 in Tape & Reel
HTSSOP16
L6910ATR
HTSSOP16 in Tape & Reel
dc-dc conversion from 3.3V, 5V and 12V buses.
The output voltage is adjustable down to 0.9V;
higher voltages can be obtained with an external
voltage divider.
High peak current gate drivers provide for fast switch-
ing to the external power section, and the output
current can be in excess of 20A.
The device assures protections against load overcur-
rent and overvoltage. An internal crowbar is also pro-
vided turning on the low side mosfet as long as the
over-voltage is detected. In case of over-current de-
tection, the soft start capacitor is discharged and the
system works in HICCUP mode.
BOOT
UGATE
BOOT
LGATE
PGND
GND
VFB
V_in 5V to 12V
V_O
Rev. 9
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