Description. Features. Application TYPICAL APPLICATION CIRCUITS

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1 Description The GM663 series is 3.A low-dropout linear voltage regulators that provide a low-voltage, and high-current output with a minimum of external components. The GM663 series offers extremely low dropout (typically 4mV at 3.A) and low ground current (typically 36mA at 3.A). The GM663 series is ideal for PC add-in cards that need to convert from standard 3.V to and to.8, down to new, lower core voltages. A guaranteed maximum dropout voltage of mv over all operating conditions allows the GM663 series to provide from a supply as low as 3V or. The GM663 series also has fast transient response, for heavy switching applications. The device requires only 47µF of output capacitance to maintain stability and achieve fast transient response. The GM663 series is fully protected with overcurrent limiting, thermal shutdown, reversed-battery protection, reversed-lead insertion protection, and reversed-leakage protection. The GM663 series offers a TTL-logic-compatible enable pin, and an error flag that indicates undervoltage and overcurrent conditions. Offered in a fixed voltages, and, the GM663 series comes in the TO- and TO-63 packages, and is an ideal upgrade to older, NPNbased linear voltage regulators. The GM663 is adjustable version. Features 3.A minimum guaranteed output current mv dropout voltage Ideal for 3.V to conversion Ideal for to conversion initial accuracy Low ground current Current limiting and Thermal shutdown Reversed-battery protection Reversed-leakage protection Fast transient response TO- and TO-63 packages TTL/CMOS compatible enable pin (GM663 only) Error flag output (GM663 only) ustable version (GM663 only) Application LDO linear regulator for PC add-in cards High-efficiency linear power supplies SMPS post regulator Multimedia and PC processor supplies Low-voltage microcontrollers TM Strong ARM processor supply TYPICAL APPLICATION CIRCUITS 3.3V GM ABLE SHUTDOWN 3.3V 47µF µf V ABLE SHUTDOWN 3.3V GM663.V kw GM V FLG 47µF 47µF ERROR FLAG PUT V. GM 43

2 MARKING INFORMATION & PIN CONFIGURATIONS TO-63- (D PAK) TO- TO-- TO-63-(D PAK) TO-- GM663 VVAYWW GM663 VVAYWW GM663 VVAYWW GM663 VVAYWW GM663 AYWW TO-63-(D PAK) V FLG FLG Pinout On all devices, the Tab is grounded. GM663 AYWW GM663/ Three Terminal Pin = Input, = Ground, 3 = Output GM663/ Five Terminal (Fixed Voltage Devices) V V A Y W W = Output Voltage (8=, =) = Assembly Location = Year = Weekly Pin = Enable, = Input, 3 = Ground, 4 = Output, = Flag GM663/ ustable with ON/ OFF Control Pin = Enable, = Input, 3 = Ground, 4 = Output, = ust ORDERING INFORMATION Ordering Number Output Voltage Package Shipping GM663 GM663-.8TA3T TO-63- GM663-.8TA3R TO-63-8 Units/ Tape & Reel GM663-.8TB3T TO- GM663-.TA3T TO-63- GM663-.TA3R TO-63-8 Units/ Tape & Reel GM663-.TB3T TO- GM663 GM663-.8TAT GM663-.8TAR GM663-.8TBT GM663-.TAT GM663-.TAR GM663-.TBT GM663 GM663TAT GM663TAR GM663TBT * For detail Ordering Number identification, please see last page. TO-63- TO-63- TO-- TO-63- TO-63- TO-- TO-63- TO-63- TO-- 8 Units/ Tape & Reel 8 Units/ Tape & Reel 8 Units/ Tape & Reel

3 PIN DESCRIPTION PIN Number GM663 PIN Number GM663 PIN NUMBER GM663 PIN Name V PIN Function Enable (Input): TTL/CMOS compatible input. Logic high=enable; logic low or open=shutdown. Unregulated Input: 6V maximum supply., TAB 3, TAB 3, TAB Ground: Ground pin and TAB are internally connected Regulator Output. FLG Error Flag (Output): Open collector output. Active low indicates an output fault condition. ustable ABSOLUTE MAXIMUM RATINGS (Note ) Parameter Symbol Value Unit Power Dissipation Supply Voltage Lead Temperature (Soldering, sec) Storage Temperature Range ESD, Note 3 P D Internally limited W - to V T LEAD T STG 6-6 to C C OPERATING RATINGS (Note ) Parameter Symbol Value Unit Supply Voltage. to 6 V Enable Voltage 6 Operating junction Temperature Range Thermal Resistance (TO-63-,TO-) Maximum Power Dissipation, Note 4 V T J -4 to C q JC. C/W V FUNCTIONAL DIAGRAM IN FLAG* * * GM663 ONLY -.8V.4V Ref. - Thermal Shut-down O.V. I Limit 8V 3

4 ELECTRICAL CHARACTERISTICS T = C, bold values indicate -4 C T C; unless noted J J Parameter Conditions Min Typ Max Unit Output Voltage Line Regulation Load Regulation Output Voltage change with Temperature Coef. Note Dropout Voltage Note 6 & 9 Ground Current Note 7 Dropout Ground Pin Current I = ma O ma I 3A, V V V 8V IN I = ma, V 8V V = V V, ma I 3A IN I = ma, D = - I = 7mA, D = - I =.A, D = - I = 3A, D = - I = 7mA, = V I =.A, = V I = 3A, = V D / DT V(nominal) -.V, I =ma ppm/ C mv ma ma Current Limit = V, = V 4. A Enable Input (Gm663) Enable Input Voltage Logic Low (off) Logic high (on)..8 V V Enable Input Current V = V =.8V Shutdown Output Current (Note 8) µa µa µa Flag Output (GM663) Output Leakage Current Output Low Voltage Low Threshold V = 6V OH V =, I = µa IN OL Note 9 of µa mv High Threshold of 99. Hysteresis Note. Exceeding the absolute maximum ratings may damage the device. Note. The device is not guaranteed to function outside its operating rating. Note 3. Devices are ESD sensitive. Handing precautions recommended. Note 4. P =(T -T ) q, where q depends upon the printed circuit layout. See "Applications Information". D(max) J(max) A JA JA Note. Output voltage temperature coefficient is DV (T - T ) where T is C and T is -4 C. (worst case) J(max) J(min) J(max) J(min) Note 6. V =V -V when V decreases to 99 of its nominal output voltage with V =V V. For voltages below, DO IN IN dropout voltage is the input-to-output voltage differential with the minimum input voltage being. Minimum input operating voltage is.v. Note 7. I is the quiescent current. I = I I IN Note 8. V.8V, V 8V, and V = V IN Note 9. For a device, V =. IN 4

5 TYPICAL CHARACTERISTICS Dropout Voltage (mv) 3 3 V = V =.8.6 I LOAD =.A.4 I LOAD = 3.A Output Current (ma) Figure. Dropout Voltage vs. Output Current Dropout Voltage (mv) 4 3 V = Temperature ( C) V = Figure. Dropout Voltage vs. Temperature Output Voltage (V).6.4. I = ma LOAD I = 3A LOAD Input Voltage(V) Figure 3. Dropout Characteristics Ground Current (ma) I = 3mA LOAD I = ma LOAD I LOAD = ma Supply Voltage (V) Figure 4. Ground Current vs. Supply Voltage Ground Current (ma) V = V = I LOAD = ma I LOAD = ma Temperature ( C) Figure. Ground Current vs. Temperature Ground Current (ma) V = V = Temperature ( C) Figure 6. Ground Current vs. Temperature Ground Current (ma) V = V = I LOAD = 3A Temperature ( C) Figure 7. Ground Current vs. Temperature Short Circuit Current (A) Typical Device Typical Device = (NOM) V = Temperature ( C) Figure 8. Short Circuit Current vs. Temperature Flag Voltage(V) Flag High (OK) Flag Low (Fault).. Resistance (k ) V = Figure 9. Error Flag Pull-up Resistor

6 APPLICATION INFORMATION The GM663 series is a high performance with lowdropout voltage regulator, suitable for moderate to high-current voltage regulator applications. Its mv dropout voltage at full load makes it especially valuable in battery-powered systems and as a high-efficiency noise filter in post-regulator applications. Unlike older NPN-pass transistor designs, where the minimum dropout voltage is limited by the base-toemitter voltage drop and collector-to-emitter saturation voltage. Dropout performance of the PNP output of these devices is limited only by the low V saturation CE Voltage. The GM663 series regulator is fully protected from damage due to fault conditions. Current limiting is provided. This limiting is linear, output current during overload conditions is constant. Thermal shutdown disables the device when the die temperature exceeds the maximum safe operating temperature. Transient protection allows device (and load) survival even when the input voltage spikes above and below nominal. The output structure of these regulators allows voltages in excess of the desired output voltage to be applied without reverse current flow. Calculate the power dissipation of the regulator from these numbers and the device parameters from this datasheet, where the ground current is taken from data sheet The heat sink thermal resistance is determined by: where T C and q is between C and C/W. P = (V - V )I V I D IN IN T J(MAX) - TA q SA = - (qjc q CS ) J(max) P D The heat sink may be significantly reduced in applications where the minimum input voltage is known and is large compared with the dropout voltage. Use a series input resistor to drop excessive voltage and distribute the heat between this resistor and the regulator. The low dropout properties of Super beta PNP regulators allow significant reductions in regulator power dissipation and the associated heat sink without compromising performance. When this technique is employed, a capacitor of at least.µf is needed directly between the input and regulator ground. CS CIN Thermal Design Figure. Capacitor Requirements Linear regulators are simple to use. The most complicated design parameters to consider are thermal characteristics. Thermal design requires four application-specific parameters: Maximum ambient temperature (T ) A Output Current (I ) Output Voltage (V ) GM663 - X.X V V IN Input Voltage (V ) IN Ground Current (I ) C Output Capacitor The GM663 series requires an output capacitor to maintain stability and improve transient response. Proper capacitor selection is important to ensure proper operation. The GM663 series output capacitor selection is dependent upon the ESR (equivalent series resistance) of the output capacitor to maintain stability. When the output capacitor is 47µF or greater, the output capacitor should have less than W of ESR. This will improve transient response as well as promote stability. Ultra-low-ESR capacitors, such as ceramic chip capacitors may promote instability. These very low ESR levels may cause an oscillation and/or underdamped transient response. When larger capacitors are used, the ESR requirement approaches zero. A µf ceramic capacitor can be used on the output while maintaining stability. A low-esr 47µF solid tantalum capacitor works extremely well and provides good transient response and stability over temperature. Aluminum electrolytics can also be used, as long as the ESR of the capacitor is W. The value of the output capacitor can be increased without limit. Higher capacitance values help to improve transient response, ripple rejection, and reduce output noise. 6

7 Input Capacitor An input capacitor of µf or greater is recommended when the device is more than 4 inches away from the bulk as supply capacitance, or when the supply is a battery. Small surfacemount ceramic chip capacitors can be used for the bypassing. Larger values will help to improve ripple rejection by bypassing the input to the regulator, further improving the integrity of the output voltage. Transient Response and 3.3V to and to Conversions The GM663 series has excellent transient response to variations in input voltage and load current. The device has been designed to respond quickly to load current variations and input voltage variations. Large output capacitors are not required to obtain this performance. A standard 47µF output capacitor, preferably tantalum, is all that is required. Larger values improve performance even further. The error flag is an open-collector output that can sink ma during a fault condition. Low output voltage can be caused by a number of problems, including an overcurrent fault (device in current limit) or low input voltage. The flag is inoperative during overtemperature shutdown. When the error flag is not used, it is best to leave it open. The flag pin can be tied directly to pin 4, the output pin. Enable Input The GM663 series version features an enable input for on/off control of the device. Its shutdown state draws "zero" current. The enable input is TTL/CMOS compatible for simple logic interface, but can be connected to up to V. When enabled, it draws approximately µa. By virtue of its low-dropout voltage, this device does not saturate into dropout as readily as similar NPNbased designs. When converting from 3.3V to or to, the NPN-based regulators are already operating in dropout, with typical dropout requirements of.v or greater. To convert down to without operating in dropout, NPN-based regulators require an input voltage of 3.7V at the very least. The GM663 series regulator will provides excellent performance with an input as low as 3.V or respectively. This gives the PNP-based regulators a distinct advantage over older, NPN-based linear regulators. A typical NPN regulator does not have the headroom to do this conversion. Minimum Load Current The GM663 series regulator is specified between finite loads. If the output current is too small, leakage currents dominate and the output voltage rises. A ma minimum load current is necessary for proper regulation. Error Flag The GM663 series version features an error flag circuit which monitors the output voltage and signals an error condition when the voltage below the nominal output voltage. 7

8 TO- PACKAGE LINE DIMSIONS 3.6 ±..3 ± ± ±. 4. ± DP. 3.7 ±. 3.8 ±. 9. ± ±..9 ±. 8.9 MAX.8 ±.3 3-R TYP (.4 ±.).8 ±.. ± ±. - R.3. ±. Unit: mm TO-- PACKAGE LINE DIMSIONS 3.6 ±..3 ± ± ±. 4. ± ±. 8. ±. 7.. DP. 3.7 ±. 3.8 ±. 9. ± ± MAX -.8 ±..7(TYP) - R.3 7. ±. 9. ±. 3-R ±. Unit: mm 8. ±.

9 TO-63- PACKAGE LINE DIMSIONS.4.4 ±. R ±..7 ±..4 TYP (.4 ±.). DP.. 9. ±. 4.9 ±..9 ±..3 ± ±..7 R.3 4. ±.. ± R ±. R.3.4 ±..4 ± ±. Pad Layout Inches ( ) mm. ±. TO-63- PACKAGE LINE DIMSIONS 4.9 ±. Unit: mm '. DP Pad Layout.3.. R.3.7 TYP (.7 ±.) R.3.7 R R Unit: mm Units: mm 9

10 ORDERING NUMBER GM 663/ 663X.8 TA3 T Gamma Micro. Circuit Type Shipping R: Tape & Reel T: Tube Output Voltage.8:.: Blank: Package TA3: TO-63- TA: TO-63- TB3: TO--3 TB: TO--

Features MIC ERROR FLAG OUTPUT V IN 3.3V IN V OUT 2.5V 3.3V OUT GND

Features MIC ERROR FLAG OUTPUT V IN 3.3V IN V OUT 2.5V 3.3V OUT GND MIC395/3951 5A µcap Low-Voltage Low-Dropout Regulator General Description The MIC395 and MIC3951 are 5A low-dropout linear voltage regulators that provide a low-voltage, high-current output with a minimum