LP38841 Datasheet, PDF (1/18 Pages) National Semiconductor (TI) – 0.8A Ultra Low Dropout Linear Regulators Stable with Ceramic Output Capacitors

LP38841
www.ti.com
SNVS289B – DECEMBER 2004 – REVISED SEPTEMBER 2006
LP38841 0.8A Ultra Low Dropout Linear Regulators
Stable with Ceramic Output Capacitors
Check for Samples: LP38841
FEATURES
1
•2 Ideal for conversion from 1.8V or 1.5V inputs
• Designed for use with low ESR ceramic
capacitors
• 0.8V, 1.2V and 1.5V standard voltages
available
• Ultra low dropout voltage (75mV @ 0.8A typ)
• 1.5% initial output accuracy
• Load regulation of 0.1%/A (typical)
• 30nA quiescent current in shutdown (typical)
• Low ground pin current at all loads
• Over temperature/over current protection
• Available in 5 lead TO220 and TO263 packages
• −40°C to +125°C junction temperature range
APPLICATIONS
• ASIC Power Supplies In:
– - Desktops, Notebooks, and Graphics
Cards, Servers
– - Gaming Set Top Boxes, Printers and
Copiers
• Server Core and I/O Supplies
• DSP and FPGA Power Supplies
• SMPS Post-Regulator
DESCRIPTION
The LP38841 is a high current, fast response regulator which can maintain output voltage regulation with
minimum input to output voltage drop. Fabricated on a CMOS process, the device operates from two input
voltages: Vbias provides voltage to drive the gate of the N-MOS power transistor, while Vin is the input voltage
which supplies power to the load. The use of an external bias rail allows the part to operate from ultra low Vin
voltages. Unlike bipolar regulators, the CMOS architecture consumes extremely low quiescent current at any
output load current. The use of an N-MOS power transistor results in wide bandwidth, yet minimum external
capacitance is required to maintain loop stability.
The fast transient response of these devices makes them suitable for use in powering DSP, Microcontroller Core
voltages and Switch Mode Power Supply post regulators. The parts are available in TO-220 and TO-263
packages.
Dropout Voltage: 75 mV (typ) @ 0.8A load current.
Quiescent Current: 30 mA (typ) at full load.
Shutdown Current: 30 nA (typ) when S/D pin is low.
Precision Output Voltage: 1.5% room temperature accuracy.
Typical Application Circuit
IN
BIAS
5V ± 10%
GND
10 PF
Ceramic
0.1 PF
LP38841
IN
OUT
BIAS
S/D
GND
4.7 PF*
OUT
S/D
GND
* Minimum value required if Tantalum capacitor is used (see Application Hints).
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2004–2006, Texas Instruments Incorporated