SBVS010D – JANUARY 2000 – REVISED SEPTEMBER 2005
500mA Low-Dropout Regulator
NEW DMOS TOPOLOGY:
Ultra Low Dropout Voltage:
115mV Typ at 500mA and 3.3V Output
Output Capacitor NOT Required for Stability
FAST TRANSIENT RESPONSE
VERY LOW NOISE: 33
= 1mA at I
Not Enabled: I
2.5V, 2.7V, 3.0V, 3.3V, 5.0V, AND ADJUSTABLE
FOLDBACK CURRENT LIMIT
OUTPUT VOLTAGE ERROR INDICATOR
SMALL SURFACE-MOUNT PACKAGES:
SOT223-5, DDPAK-5, SO-8
The REG103 is a family of low-noise, low-dropout, linear
regulators with low ground pin current. Its new DMOS
topology provides significant improvement over previous
designs, including low-dropout voltage (only 115mV typ at
full load), and better transient performance. In addition, no
output capacitor is required for stability, unlike conventional
low-dropout regulators that are difficult to compensate and
require expensive low ESR capacitors greater than 1µF.
Typical ground pin current is only 1mA (at I
and drops to 0.5µA in
mode. Unlike regulators
with PNP pass devices, quiescent current remains relatively
constant over load variations and under dropout conditions.
The REG103 has very low output noise (typically 33µVrms
= 3.3V with C
= 0.01µF), making it ideal for use
in portable communications equipment. On-chip trimming
results in high output voltage accuracy. Accuracy is main-
tained over temperature, line, and load variations. Key
parameters are tested over the specified temperature range
(–40°C to +85°C).
The SO-8 version of the REG103 has an ERROR pin that
flag, indicating the regulator is in
regulation. The REG103 is well protected—internal cir-
cuitry provides a current limit that protects the load from
damage. Thermal protection circuitry keeps the chip from
being damaged by excessive temperature. In addition to the
SO-8 package, the REG103 is also available in the DDPAK
and the SOT223-5.
PORTABLE COMMUNICATION DEVICES
PERSONAL DIGITAL ASSISTANTS
BACKUP POWER SUPPLIES
NR = Noise Reduction
NOTE: (1) SO-8 Package Only. (2) Optional.
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright © 2000-2005, Texas Instruments Incorporated