1 Features
1• Input Voltage Range: 0.7 V to 4.5 V
• 2.5 V ≤ V BATT ≤ 5.5 V
• 0.5V ≤ VOUT ≤ 2 V
• Ensured 350-mA Output Current
• For ILOAD = 350 mA:
– VBATT ≥ VOUT(NOM) + 1.5 V or 2.5 V
(Whichever is Higher)
• For ILOAD = 150 mA:
– VBATT ≥ VOUT(NOM) + 1.3 V or 2.5 V
(Whichever is Higher)
• Excellent Load Transient Response: ±15 mV
Typical
• Excellent Line Transient Response: ±1 mV Typical
• 50-μA Typical Quiescent Current from VBATT
• 10-μA Typical Quiescent Current from VIN
• 0.1-μA Typical Quiescent Current in Shutdown
• Noise voltage = 100 μVRMS Typical
• Operates from a Single Li-Ion Cell or 3-Cell
NiMH/NiCd Battery
• Thermal-Overload and Short-Circuit Protection

2 Applications
• Mobile Phones
• Hand-Held Radios
• Personal Digital Assistants
• Palm-Top PCs
• Portable Instruments
• Battery-Powered Devices

3 Description
The LP5952 is a dual-supply-rail linear regulator
optimized for powering ultralow-voltage circuits from a
single Li-Ion cell or 3-cell NiMH/NiCd battery.
In the typical post-regulation application VBATT is
directly connected to the battery (range 2.5 V to
5.5 V), and VIN is supplied by the output voltage of
the DC-DC converter (range 0.7 V to 4.5 V).
The device offers superior dropout and transient
features combined with very low quiescent currents.
In shutdown mode (Enable (EN) pin pulled low) the
device turns off and reduces battery consumption to
0.1 μA (typical). The LP5952 also features internal
protection against overtemperature, overcurrent, and
undervoltage conditions.
Depending upon application, only one or two tiny
surface-mount external components are required;
performance is specified for a –40°C to +125°C
junction temperature range. The device is available in
fixed output voltages from 0.5 V to 2 V. For
availability, please contact your local Texas
Instruments sales office.