MIC2940A/2941A 1.2A Low-Dropout Voltage Regulator General Description Features The MIC2940A and MIC2941A are bulletproof efficient High output voltage accuracy voltage regulators with very low dropout voltage (typically Guaranteed 1.25A output 40mV at light loads and 350mV at 1A), and low quiescent Low quiescent current current (240A typical). The quiescent current of the Low dropout voltage MIC2940A increases only slightly in dropout, thus Extremely tight load and line regulation prolonging battery life. Key MIC2940A features include Very low temperature coefcient protection against reversed battery, fold-back current Current and thermal limiting limiting, and automotive load dump protection (60V Input can withstand 20V reverse battery and +60V positive transient). positive transients The MIC2940 is available in both xed voltage (3.3V, 5V, Logic-controlled electronic shutdown and 12V) and adjustable voltage congurations. The Output programmable from 1.24V to 26V(MIC2941A) MIC2940A-xx devices are three pin, xed voltage regulators. A logic-compatible shutdown input is provided Available in TO-220, TO-263, TO-220-5, and TO-263-5 on the adjustable MIC2941A, which enables the regulator packages. to be switched on and off. Data sheets and support documentation can be found on Applications Micrels web site at: www.micrel.com. 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 Pin Configuration 12 3 4 5 12 3 TO-263-5 TO-263-3 (MIC2941ABU/WU) (MIC2940A-xxBU/WU) MIC2941A Pinout 12 3 MIC2940A Pinout 12 3 4 5 1) Adjust 1) Input 2) Shutdown 2) Ground TO-220-3 TO-220-5 3) Ground 3) Output (MIC2940A-xxBT/WT) (MIC2941ABT/WT) 4) Input 5) Output The TAB is Ground on TO-220 and TO-263 packages Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MIC2940A/2941A Ordering Information Part Number Voltage Temperature Range Package Lead Finish MIC2940A-3.3BT 3.3V 40 to +125C 3-Pin TO-220 Standard MIC2940A-3.3BU 3.3V 40 to +125C 3-Pin TO-263 Standard (1) MIC2940A-3.3WT 3.3V 40 to +125C 3-Pin TO-220 RoHS Comliant (1) MIC2940A-3.3WU 3.3V 40 to +125C 3-Pin TO-263 RoHS Comliant MIC2940A-5.0BT 5V 40 to +125C 3-Pin TO-220 Standard MIC2940A-5.0BU 5V 40 to +125C 3-Pin TO-263 Standard (1) MIC2940A-5.0WT 5V 40 to +125C 3-Pin TO-220 RoHS Comliant (1) MIC2940A-5.0WU 5V 40 to +125C 3-Pin TO-263 RoHS Comliant MIC2940A-12BT 12V 40 to +125C 3-Pin TO-220 Standard MIC2940A-12BU 12V 40 to +125C 3-Pin TO-263 Standard (1) MIC2940A-12WT 12V 40 to +125C 3-Pin TO-220 RoHS Comliant (1) MIC2940A-12WU 12V 40 to +125C 3-Pin TO-263 RoHS Comliant MIC2941ABT Adj. 40 to +125C 5-Pin TO-220 Standard MIC2941ABU Adj. 40 to +125C 5-Pin TO-263 Standard (1) MIC2941AWT Adj. 40 to +125C 5-Pin TO-220 RoHS Comliant (1) MIC2941AWU Adj. 40 to +125C 5-Pin TO-263 RoHS Comliant Note: 1. RoHS compliant with hot-melting solder exemption. Schematic Diagram M9999-071307 July 2007 2