LP2951 100 mA Low-Dropout Voltage Regulator Features General Description High Accuracy 5V, Guaranteed 100 mA Output The LP2951 is micropower voltage regulators with very low dropout voltage (typically 40 mV at light loads and Extremely Low Quiescent Current 380 mV at 100 mA), and very low quiescent current Low-Dropout Voltage (75 A typical). The quiescent current of the LP2951 Extremely Tight Load and Line Regulation increases only slightly in dropout, thus prolonging Very Low Temperature Coefficient battery life. This feature, among others, makes the Use as Regulator or Reference LP2951 ideally suited for use in battery-powered systems. Needs Only 1 F for Stability Current and Thermal Limiting Available system functions, such as programmable output voltage and logic-controlled shutdown, are Error Flag Warns of Output Dropout available as well. Logic-Controlled Electronic Shutdown Additional features available with the LP2951 also Output Programmable from 1.24V to 29V include an error flag output that warns of a low output Applications voltage, which is often due to failing batteries on the Automotive Electronics input. This may also be used as a power-on reset. A logic-compatible shutdown input is also available which Voltage Reference enables the regulator to be switched on and off. This Avionics part may also be pin-strapped for a 5V output, or programmed from 1.24V to 29V with the use of two external resistors. The LP2951 is available as either a -02 or -03 version. The -02 and -03 versions are guaranteed for junction temperatures from -40C to +125C the -02 version has a tighter output and reference voltage specification range over temperature. The LP2951 have a tight initial tolerance (0.5% typical), a very low output voltage temperature coefficient which allows use as a low-power voltage reference, and extremely good load and line regulation (0.05% typical). This greatly reduces the error in the overall circuit, and is the result of careful design techniques and process control. Package Types LP2951 DIP & SOIC Top View 1 8 INPUT OUTPUT 2 7 SENSE FEEDBACK 3 6 SHUTDOWN 5V TAP 4 5 GROUND ERROR * See MIC2950 for a part with: 1) higher output (150 mA), 2) transient protection (60V), and 3) reverse input protection to 20V. 2017 Microchip Technology Inc. DS20005736A-page 1LP2951 Functional Block Diagram UNREGULATED DC 5V 150 mA MAX. 7 8 1 + FEEDBACK INPUT OUTPUT 2 SENSE + 182 6 k 3 ERROR 330 FROM 5V TAP AMPLIFIER SHUT- + k CMOS 1.5 F DOWN 60 mV 60 OR TTL 5 + k + TO CMOS ERROR ERROR OR TTL + DETECTION 1.23 V 4 COMPARATOR REF. GROUND Typical Application Diagrams +V +V IN IN C-MOS GATE *SLEEP 8 INPUT +V IN 470 k 47k ERROR 1 *V V 8 5 OUT IN ERROR V OUT +V IN OUTPUT +V OUT 1 LP2951 ERROR 5 V OUT ERROR OUTPUT SHUTDOWN 3 200k MIC2951LP2951 SO 1% 3 + INPUT 2N3906 SHUTDOWN SD 3.3F 100k INPUT 100pF GND FB OFF FB GND ON 7 4 7 4 1% 100k *MINIMUM INPUT-OUTPUT VOLTAGE RANGES FROM 40 mV TO 400 mV, DEPENDING ON LOAD CURRENT. CURRENT LIMIT IS TYPICALLY 160 mA. *HIGH INPUT LOWERS V TO 2.5V OUT WIDE INPUT VOLTAGE RANGE 5V REGULATOR WITH 2.5V CURRENT LIMITER SLEEP FUNCTION +V = 2 30V 1.23 I LILOAD = L R 8 V IN 1 V OUT LP2951 SHUTDOWN 3 0.1F SD INPUT GND FB 4 7 R 1F 1% LOW DRIFT CURRENT SOURCE DS20005736A-page 2 2017 Microchip Technology Inc.