3A Step-Down Voltage Regulator
AMS2576
GENERAL DESCRIPTION
The
AMS2576
Series are step-down switching
regulators with all required active functions. It is
capable of driving 3A load with excellent line and
load regulations. These devices are available in
fixed output voltages of 3.3V, 5V, 12V and an
adjustable output version.
The
AMS2576
series offers a high-efficiency
replacement for popular three-terminal linear
regulators. Also it requires a minimum number of
external components. It substantially not only
reduces the area of board size but also the size of
heat sink, and in some cases no heat sink is
required. The ±4% tolerance on output voltage
within specified input voltages and output load
conditions is guaranteed. Also, the oscillator
frequency accuracy is within ±10%. External
shutdown is included. Featuring 80µA (typical)
standby current. The output switch includes
cycle-by-cycle current limiting, as well as thermal
shutdown for full protection under fault conditions.
This series are offered in 5-pin TO-263,
TO-220 package.
FEATURES
3.3V, 5V, 12Vand adjustable versions
Wide input voltage range, up to 40V
Internal oscillator of 52KHz fixed frequency
Guaranteed 3A output current
Wide adjust version output voltage range
from 1.23V to 37V ±4% max. at over line and
load conditions
Low standby current, typ. 80µA, at shutdown
mode
Requires only 4 external components
Thermal shutdown and current limit
protection
APPLICATIONS
LCD Monitors.
ADD-ON Cards Switching Regulators
High Efficiency Step-Down Regulators
Efficient Pre-regulator for Linear Regulators
Positive to Negative converter (Buck-Boost)
Block Diagram
DC Input
+
Vin
1
Internal
Regulator
Enable
5
Enable
4
Feed
Back
R2
+
R1
1K
Fixed Gain
Error amp. Comparator
3Amp.
Driver Switch
L1
+
Cout
D1
LOAD
-
+
-
2
Thermal
Shutdown
3
Current
Limited
Output
1.23V
Band-Gap
Reference
52KHz
Oscillator
Reset
1
Advanced Monolithic Systems
http://www.ams-semitech.com
AMS [ Advanced Monolithic Systems Ltd ]
