LP2950/LP2951 Series of Adjustable Micropower Voltage Regulators
General Description
The LP2950 and LP2951 are micropower voltage regulators with very
low quiescent current (75µA typ.) and very low dropout voltage
(typ. 40mV at light loads and 380mV at 100mA). They are ideally
suited for use in battery-powered systems. Furthermore, the
quiescent current of the LP2950/ LP2951 increases only slightly in
dropout, prolonging battery life. The LP2950-5.0 is available in
the surface-mount D-Pak package, and in the popular 3-pin TO-92
package for pincompatibility with older 5V regulators. The 8-lead
LP2951 is available in plastic, ceramic dual-in-line, LLP, or metal
can packages and offers additional system functions. One such
feature is an error flag output which warns of a low output
voltage, often due to falling batteries on the input. It may be
used for a power-on reset. A second feature is the logic-compatible
shutdown input which enables the regulator to be switched on and
off. Also, the part may be pin-strapped for a 5V, 3V, or 3.3V
output (depending on the version), or programmed from 1.24V to 29V
with an external pair of resistors. Careful design of the
LP2950/LP2951 has minimized all contributions to the error budget.
This includes a tight initial tolerance (.5% typ.), extremely good
load and line regulation
Features
n 5V, 3V, and 3.3V versions available
n High accuracy output voltage
n Guaranteed 100mA output current
n Extremely low quiescent current
n Low dropout voltage
n Extremely tight load and line regulation
n Very low temperature coefficient
n Use as Regulator or Reference
n Needs minimum capacitance for stability
n Current and Thermal Limiting
n Stable with low-ESR output capacitors (10mΩ to 6Ω)
LP2951 versions only
n Error flag warns of output dropout
n Logic-controlled electronic shutdown
n Output programmable from 1.24 to 29V
