MIC47300 3A, Low Voltage, Adjustable LDO Regulator with Dual Input Supply General Description Features The MIC47300 is a high-bandwidth, low-dropout, 3A volt- Input Voltage Range: age regulator ideal for powering core voltages of low- V : 1.4V to 6.5V IN power microprocessors. The MIC47300 implements a dual V : 3.0V to 6.5V BIAS supply conguration allowing for very low output Stable with 1F ceramic capacitor impedance and very fast transient response. 1% initial tolerance The MIC47300 requires a bias input supply between 3V Maximum dropout voltage (V V ) of 400mV and 6.5V for proper operation. The main input supply rail IN OUT over temperature operates from 1.4V to 6.5V that allows for adjustable output voltages down to 0.9V. Adjustable output voltage down to 0.9V The MIC47300 requires a minimum of 1F output Ultra fast transient response (Up to 10MHz bandwidth) capacitance for stability, and optimal operation is achieved Excellent line and load regulation specifications with small ceramic capacitors. Power D-Pak package (TO-252) The MIC47300 is available in a 5-pin power D-Pak Thermal shutdown and current-limit protection package (TO-252) with an operating temperature range of Junction temperature range: 40C to 125C 40C to +125C. Datasheets and support documentation can be found on Applications Micrels web site at: www.micrel.com. Graphics processors PC add-in cards Microprocessor core voltage supply Low voltage digital ICs High efficiency linear power supplies SMPS post regulators Typical Application* Figure 1. Typical Application Circuit *See Thermal Design Section Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MIC47300 Ordering Information Part Number Output Current Voltage Junction Temp. Range Package MIC47300WD* 3A Adjustable 40 to +125C 5-Pin TO-252 Note: * RoHs compliant with high-melting solder exemption. Pin Configuration 5-Pin TO-252 D-Pak (D) Pin Description Pin Number Pin Name Pin Name 1 ADJ Adjustable Regulator Feedback Input: Connect to the resistor voltage divider that is placed from OUT to GND in order to set the output voltage. 2 BIAS Input Bias Voltage: Voltage for powering all internal circuitry of the regulator with the exception of the output power device. 3 GND, TAB Ground: TAB is also connected internally to the ICs ground on D-Pak. 4 IN Input Voltage: Supplies the current to the output power device 5 OUT Regulator Output: The output voltage is set by the resistor divider connected from OUT to GND (with the divided connection tied to ADJ). A minimum value capacitor must be used to maintain stability. See Applications Information. October 2009 2 M9999-102309-A