AIC1117
800mA Low Dropout Positive Adjustable
Regulator
Analog Integrations Corporation 4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC www.analog.com.tw
DS-1117-00 Mar 13, 00 TEL: 886-3-5772500 FAX: 886-3-5772510 1
n FEATURES
l Dropout Voltage 1.2V at 800mA Output Current.
l Fast Transient Response.
l Line Regulation typically at 0.015%.
l Load Regulation typically at 0.1%.
l Internal Thermal and Current Limiting.
l Adjustable Output Voltage or Fixed 2.85V, 3.3V,
5V.
l Standard 3-Pin Power Packages.
n APPLICATIONS
l SCSI-2 Active Terminator.
l Post Regulator for Switching Supply.
l Battery Chargers.
l Constant-Current Regulators.
l PC Add-On Card.
n DESCRIPTION
The AIC1117 is a low dropout three terminal
regulator with 800mA output current capability.
The output voltage is adjustable with the use
of a resistor divider. For fixed output voltage
versions, the output voltage is internally set at
2.85V, 3.3V or 5V. Dropout is guaranteed at a
maximum of 1.3V at maximum output current.
Its low dropout voltage and fast transient
response make it ideal for low voltage
microprocessor applications. Internal current
and thermal limiting provides protection
against any overload condition that would
create excessive junction temperatures.
n TYPICAL APPLICATION CIRCUIT
C2
10µF
VOUT
3.3V
VIN
5V
+
+ VREF
RF2
205Ω
1%
ADJ
AIC1117
C1
10µF
23
1 RF1125Ω
1%
VREF=VOUT - VADJ=1.25V (typ.)
VOUT=VREF x (1+RF2/RF1)+ IADJ x RF2
IADJ=55µA (typ.)
(1) C1 needed if device is far away from filter
capacitors.
(2) C2 required for stability.
Adjustable Voltage Regulator

C2
10µF
VOUTVIN
5V
+
+
GND
C1
10µF
AIC1117-28
AIC1117-33
AIC1117-50
2
1
3
Fixed Voltage Regulator