MIC5202. Dual 100mA Low-Dropout Voltage Regulator. Features. General Description. Pin Configuration. Ordering Information. Typical Application

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1 MIC MIC Dual ma Low-Dropout Voltage Regulator Preliminary Information General Description The MIC is a family of dual linear voltage regulators with very low dropout voltage (typically 7mV at light loads and mv at ma), and very low ground current (ma at ma output each section), offering better than % initial accuracy with a logic compatible ON/OFF switching input. Designed especially for hand-held battery powered devices, the MIC is switched by a CMOS or TTL compatible logic signal. This ENABLE control my be tied directly to V IN if unneeded. When disabled, power consumption drops nearly to zero. The ground current of the MIC increases only slightly in dropout, further prolonging battery life. Key MIC features include protection against reversed battery, current limiting, and over-temperature shutdown. The MIC is available in several fixed voltages. Other options are available; contact for details. Features High output voltage accuracy Variety of output voltages Guaranteed ma output Low quiescent current Low dropout voltage Extremely tight load and line regulation Very low temperature coefficient Current and thermal limiting Reverse-battery protection Zero OFF mode current Logic-controlled electronic shutdown Available in SO-8 package Applications Cellular Telephones Laptop, Notebook, and Palmtop Computers Battery Powered Equipment PCMCIA V CC and V PP Regulation/Switching Bar Code Scanners SMPS Post-Regulator/ DC to DC Modules High Efficiency Linear Power Supplies Ordering Information Part Number Volts Accuracy Temperature Range* Package MIC-.BM. % C to + C SO-8 MIC-.BM. % C to + C SO-8 MIC-.8BM.8 % C to + C SO-8 MIC-.BM. % C to + C SO-8 * Junction Temperature Other voltages are available; contact for details. Typical Application Pin Configuration V OUT (A) GROUND V OUT (B) GROUND MIC-xxBM V IN (A) ENABLE (A) V IN (B) ENABLE (B) Both GROUND pins must be tied to the same potential. V IN (A) and V IN (B) may run from separate supplies. MIC-. Output B Output A µ (x) Enable A Enable B ENABLE pins may be tied directly to V IN 997 -

2 MIC Absolute Maximum Ratings Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Electrical specifications do not apply when operating the device beyond its specified Operating Ratings. Recommended Operating Conditions Input Voltage....V to 6V Operating Junction Temperature Range... C to + C ENABLE Input Voltage... V to V IN Power Dissipation... Internally Limited Lead Temperature (Soldering, seconds)... 6 C Operating Junction Temperature Range... C to + C Input Supply Voltage... V to +6V ENABLE Input Voltage... V to +6V ESD Rating... > V SO-8 θ JA... See Note Electrical Characteristics Limits in standard typeface are for T J = C and limits in boldface apply over the junction temperature range of C to + C. Specifications are for each half of the (dual) MIC. Unless otherwise specified, V IN = V OUT + V,, C L = µf, and V CONTROL.V. Symbol Parameter Condition Min Typ Max Units V O Output Voltage Variation from specified V OUT % Accuracy V O Output Voltage (Note ) ppm/ C T Temperature Coef. V O Line Regulation V IN = V OUT + V to 6V.. % V O. V O Load Regulation I L =.ma to ma (Note )..6 % V O. V IN V O Dropout Voltage I L = µa 7 mv (Note ) I L = ma I L = ma I L = ma 8 I Q Quiescent Current V CONTROL.7V (Shutdown). µa I GND Ground Pin Current V CONTROL.V, I L = µa 7 µa I L = ma 7 I L = ma I L = ma PSRR Ripple Rejection 7 db I GNDDO Ground Pin V IN =.V less specified V OUT, I L = µa 7 µa Current at Dropout (Note ) I LIMIT Current Limit V OUT = V 8 ma V O Thermal Regulation (Note 6). %/W P D e n Output Noise µv Control Input Input Voltage Level V IL Logic Low OFF.7 V Logic High ON. I IL Control Input Current V IL.7V. µa IH V IH.V

3 MIC Note : Note : Note : Note : Note : Note 6: Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the device outside of its rated operating conditions. The maximum allowable power dissipation is a function of the maximum junction temperature, T J(MAX) the junction-to-ambient thermal resistance, θ JA, and the ambient temperature, T A. The maximum allowable power dissipation at any ambient temperature is calculated using: P (MAX) = (T J(MAX) T A ) / θ JA. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The junction to ambient thermal resistance of the MICBM is 6 C/W mounted on a PC board. Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load range from.ma to ma. Changes in output voltage due to heating effects are covered by the thermal regulation specification. Dropout Voltage is defined as the input to output differential at which the output voltage drops % below its nominal value measured at V differential. Ground pin current is the regulator quiescent current plus pass transistor base current. The total current drawn from the supply is the sum of the load current plus the ground pin current. Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load or line regulation effects. Specifications are for a ma load pulse at V IN = 6V for T = ms, and is measured separately for each section. Typical Characteristics (Each Regulator Regulators/Package) Dropout Voltage vs. Output Current. Dropout Voltage. Dropout Characteristics DROPOUT VOLTAGE (mv) DROPOUT VOLTAGE (V)... OUTPUT VOLTAGE (V) I L = µa, ma.. OUTPUT CURRENT (ma) INPUT VOLTAGE (V) vs. Output Current... OUTPUT CURRENT (ma) vs. Supply Voltage. 6 8 SUPPLY VOLTAGE (V) OUTPUT VOLTAGE (V) Output Voltage vs. Output Current..... OUTPUT CURRENT (A) 997-7

4 MIC... I LOAD = µa I LOAD = ma. - LOAD (ma) - Thermal Regulation (.V Version) C L =.7 µf - - OUTPUT VOLTAGE (V) Output Voltage vs. Temp. (.V Version) DEVICES: HI / AVG / LO. CURVES APPLICABLE AT µa AND ma OUTPUT CURRENT (ma) Output Current V OUT =.V V OUT = V (SHORT CIRCUIT) MIN. INPUT VOLTAGE (V) Minimum Input Voltage I LOAD = ma SHORT CIRCUIT CURRENT (ma) Short Circuit Current vs. Input Voltage V OUT =.V 6 7 INPUT VOLTAGE (V) OUTPUT (ma) Load Transient C L =.7µF OUTPUT (ma) Load Transient C L = 7µF - SUPPLY CURRENT (ma) 8 6 Supply Current vs. Supply Voltage (.V Version) R L = Ω INPUT (V) Line Transient C L = µf INPUT (V) Line Transient C L = µf SUPPLY VOLTAGE (V)

5 MIC SUPPLY CURRENT (ma) 6 Supply Current vs. Supply Voltage (.V Version) R L = 66Ω 6 7 SUPPLY VOLTAGE (V) OUTPUT (V) ENABLE (V) - Enable Transient (.V Version) C L =.7 µf - - TIME (µs) OUTPUT (V) ENABLE (V) - Enable Transient (.V Version) C L =.7 µf - - TIME (µs) OUTPUT IMPEDANCE (Ω).. Output Impedance I L = µa ENABLE CURRENT (µa) Enable Current Threshold V EN = V V EN = V ENABLE VOLTAGE (V) Enable Voltage Threshold OFF ON. x x x x x x x Ripple vs. Frequency Ripple vs. Frequency Ripple vs. Frequency RIPPLE VOLTAGE (db) 8 6 I L = µa RIPPLE VOLTAGE (db) 8 6 RIPPLE VOLTAGE (db) 8 6 x x x x x x 6 x x x x x x 6 x x x x x x

6 MIC Applications Information External Capacitors A µf capacitor is recommended between the MIC output and ground to prevent oscillations due to instability. Larger values serve to improve the regulator's transient response. Most types of tantalum or aluminum electrolytics will be adequate; film types will work, but are costly and therefore not recommended. Many aluminum electrolytics have electrolytes that freeze at about C, so solid tantalums are recommended for operation below C. The important parameters of the capacitor are an effective series resistance of about Ω or less and a resonant frequency above khz. The value of this capacitor may be increased without limit. At lower values of output current, less output capacitance is required for output stability. The capacitor can be reduced to.7µf for current below ma or.µf for currents below ma. A µf capacitor should be placed from the MIC input to ground if there is more than inches of wire between the input and the AC filter capacitor or if a battery is used as the supply. ENABLE Input The MIC features nearly zero OFF mode current. When the ENABLE input is held below.7v, all internal circuitry is powered off. Pulling this pin high (over.v) re-enables the device and allows operation. The ENABLE pin requires a small amount of current, typically µa. While the logic threshold is TTL/CMOS compatible, ENABLE may be pulled as high as V, independent of the voltage on V IN. The two portions of the MIC may be enabled separately. Thermal Considerations Part I. Layout PC Board Dielectric FR Ceramic θ JA The MIC-xxBM (8-pin surface mount package) has the following thermal characteristics when mounted on a single layer copper-clad printed circuit board. 6 C/W C/W Multi-layer boards having a ground plane, wide traces near the pads, and large supply bus lines provide better thermal conductivity. The "worst case" value of 6 C/W assumes no ground plane, minimum trace widths, and a FR material board. Part II. Nominal Power Dissipation and Die Temperature The MIC-xxBM at a C ambient temperature will operate reliably at up to 6mW power dissipation when mounted in the "worst case" manner described above. At an ambient temperature of C, the device may safely dissipate mw. These power levels are equivalent to a die temperature of C, the recommended maximum temperature for non-military grade silicon integrated circuits. General Notes The MIC will remain stable and in regulation with no load in addition to the internal voltage divider, unlike many other voltage regulators. This is especially important in CMOS RAM keep-alive applications. Thermal shutdown is independant on both halfs of the dual MIC, however an over-temperature condition on one half might affect the other because of proximity. When used in dual supply systems where the regulator load is returned to a negative supply, the output voltage must be diode clamped to ground. mil mil mil Both MIC GROUND pins must be tied to the same ground potential. Isolation between the two halfs allows connecting the two V IN pins to different supplies. mil mil Minimum recommended board pad size, SO