G5503 Datasheet, PDF (1/1 Pages) Global Mixed-mode Technology Inc – 300KHz, 3A Buck Converter

Global Mixed-mode Technology Inc.
300KHz, 3A Buck Converter
G5503
Features
„ Voltage Mode Asynchronous PWM Control
„ 3.3V, 5V and Adjustable Output Version
„ Operation Voltage can be up to 20V
„ Adjustable Version Output Voltage Range, 0.8V
to 16V±2%
„ 300KHz Fixed Frequency Internal Oscillator
„ Built-in Switching Transistor on Chip
„ 3A Output Load Current
„ Thermal Shutdown and Current Limit Protec-
tion
„ ON/OFF Shutdown Control
„ Iq of Low Power Standby Mode 1µA
„ Available in SOP-8 Packages
Applications
„ Simple high-efficiency step-down regulator
„ On-card switching regulators
„ Positive to negative converter
General Description
The G5503 is a voltage-mode buck PWM converter
capable of driving up to 3A loads over a wide input
supply range. High efficiency is obtained through the
use of a low R_DS(ON) P-channel power switch. The in-
ternal compensation makes feedback control have
excellent line and load regulation characteristics with-
out external designs.
It uses a fixed switching frequency of 300KHz. The
output voltage is 3.3V, 5V and an user-programmable
version via an external resistive voltage divider. The
built-in soft-start can reduce inrush current on the input
source at turn on.
The device also has built-in current-limit, thermal
shutdown, under-voltage lockout and an ON/OFF
logic-control that can power down the regulator to a
shutdown mode. When current limit function occurred
and V_FB is down to 0.3V below, the device changes
switching frequency to 120KHz to protect IC from
damage.
G5503 is available in SOP-8 package.
Ordering Information
ORDER
NUMBER
G5503-ADJP11U
G5503-33P11U
G5503-50P11U
Note: P1: SOP-8
1: Bonding Code
U: Tape & Reel
MARKING
5503A
5503B
5503C
Pin Configuration
VOLTAGE
Adjustable
3.3V
5.0V
TEMP.
RANGE
-40°C~85°C
-40°C~85°C
-40°C~85°C
PACKAGE
(Pb free)
SOP-8
SOP-8
SOP-8
Typical Application Circuit
FB 1
EN 2
NC 3
IN 4
G5503
SOP-8
8 NC
7 GND
6 LX
5 NC
VIN
6V~18V
470µF 1µF
G5503
IN
LX
EN
FB
GND
33µH
D1
SCD36 R1/31.25K 220µF
1µF*
VOUT
3.3V/2A
R2/10K
( ) ^R1
VOUT = 0.8 x
1+
R2
* optional
Ver: 0.1
May 02, 2008
TEL: [phone]
http://www.gmt.com.tw
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