MIC2954 250mA Low-Dropout Regulator - Micrel - #1

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MIC2954 250mA Low-Dropout Regulator Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com September 2007 M9999-090607 General Description The MIC2954 is a “bulletproof” efficient voltage regulator with very low dropout voltage (typically 40mV @ light loads and 375mV @ 250mA), and low quiescent current (120ìA typical). The quiescent current of the MIC2954 increases only slightly in dropout, thus prolonging battery life. Key MIC2954 features include protection against reversed battery, fold-back current limiting, and automotive load dump protection (60V positive transient). The MIC2954-07/08BM is an adjustable version that includes an error flag output that warns of a low output voltage, which is often due to failing batteries on the input. This may also be used as a power-on reset. A logiccompatible shutdown input is provided which enables the regulator to be switched on and off. This part may be pinstrapped for 5V output, or programmed from 1.24V to 29V with the use of two external resistors. The MIC2954 is available in two voltage tolerances, ±0.5% maximum and ±1% maximum. Both are guaranteed for junction temperatures from –40°C to +125°C. Data sheets and support documentation can be found on Micrel’s web site at www.micrel.com. Features • High-accuracy 5V, guaranteed 250mA output • Low quiescent current • Low dropout voltage • Extremely tight load and line regulation • Very low temperature coefficient • Current and thermal limiting • Input can withstand –20V reverse battery and+60V positive transients • Error flag warns of low output voltage • Logic-controlled electronic shutdown • Output programmable from 1.24V to 29V (MIC2954-07/08) • Available in TO-220, TO-92, and surface-mount SOT- 223 and SOIC-8 packages Applications • Battery powered equipment • Cellular telephones • Laptop, notebook, and palmtop computers • PCMCIA VCC and VPP regulation/switching • Bar code scanners • Automotive electronics • SMPS post-regulator/dc-to-dc modules • Voltage reference • High-efficiency linear power supplies ___________________________________________________________________________________________________________ Ordering Information Part Number Standard Pb-Free / RoHS Compliant Accuracy Junction Temp. Range Package MIC2954-02BT MIC2954-02WT* 0.5% –40° to +125°C TO-220-3 MIC2954-03BT MIC2954-03WT* 1.0% –40° to +125°C TO-220-3 MIC2954-02BS MIC2954-02WS* 0.5% –40° to +125°C SOT-223-3 MIC2954-03BS MIC2954-03WS* 1.0% –40° to +125°C SOT-223-3 MIC2954-02BZ MIC2954-02YZ 0.5% –40° to +125°C TO-92-3** MIC2954-03BZ MIC2954-03YZ 1.0% –40° to +125°C TO-92-3** MIC2954-07BM MIC2954-07YM 0.5% –40° to +125°C 8-Pin SOIC MIC2954-08BM MIC2954-08YM 1.0% –40° to +125°C 8-Pin SOIC * RoHS compliant with ‘high-melting solder’ exemption. ** TO-92 package discontinuance notification issued September 2007. End-of-life-buy offered thru December 31, 2007. Contact factory for additional information.