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LP3994
50mA CMOS Voltage Regulator with Enable Control
General Description
The LP3994 regulator provides 1.5V and 1.8V outputs op-
tions at up to 50mA load current. The LP3994 provides an
accurate output voltage with low quiescent current at full
current. Good noise performance is obtained without a noise
bypass capacitor. The low quiescent current in operation can
be reduced to virtually zero when the device is disabled via
a logic signal to the enable input. In conjuction with small
space saving capacitors, the small package size of the mi-
croSMD devices results in a regulator solution with a very
small footprint for any given application.
The LP3994 is suitable for general use within the range of
portable, battery-powered equipment and voltage options
other than 1.5V and 1.8V can be made available.
The
LP3994
also
features
short-circuit
and
thermal-
shutdown protection.
Performance is specified for a -40C to 125C temperature
range.
This device is available with output voltages of 1.5V and
1.8V in both microSMD and LLP packages. Other voltages
and alternative packages may be made available, please
contact your local NSC sales office.
Features
n
4 Pin MicroSMD Package/ 6 Pin LLP
n
No Noise Bypass Capacitor Required
n
Logic Controlled Enable
n
Stable with Low ESR Ceramic Capacitors
n
Fast turn on time
n
Thermal-Overload and Short Circuit Protection
Key Specifications
n
Input Voltage Range
n
Output Voltage Range
n
Output Current
n
Noise Figure
n
PSRR
n
Fast Startup
n
Output Capacitor
n
Virtually Zero I
Q
(Disabled)
2.5 to 5.5V
1.5 to 3.3V
50mA
95μV
RMS
70dB
10μs
1μF Low ESR
0.001μA
Package
Tiny 4 Pin micro SMD
6 pin LLP
1mm by 1mm by 0.6m
SOT23 footprint
Applications
n
Bluetooth Devices
n
Battery Powered Devices
n
Portable Information Appliances
Typical Application Circuit
20046501
August 2004
L
2004 National Semiconductor Corporation
DS200465
www.national.com