MIC37501/37502 5A, Low Voltage μCap LDO Regulator General Description Features The MIC37501 and MIC37502 are 5A, low dropout • 5A minimum guaranteed output current linear voltage regulator that provide low voltage, high • 500mV maximum dropout voltage current outputs with a minimum of external components. – Ideal for 3.0V to 2.5V conversion They offer high precision, ultra-low dropout (500mV), – Ideal for 2.5V to 1.8V, 1.65V, or 1.5V and low ground current. conversion The MIC37501and MIC37502 operate from an input of • Stable with ceramic or tantalum capacitor 2.3V to 6.0V. They are designed to drive digital circuits • Wide input voltage range: requiring low voltage at high currents (i.e., PLDs, DSPs, - V : 2.3V to 6.0V microcontrollers, etc.). They are available in fixed and IN • ±1.0% initial output tolerance adjustable output voltages. Fixed voltages include 1.5V, 1.65V, 1.8V, 2.5V, and 3.3V. The adjustable version is • Fixed and adjustable output voltages: capable of 1.24V to 5.5V. – MIC37501—7 terminal fixed voltage – MIC37502—5 (TO-263) and 7 (SPAK) terminal MIC37501 and MIC37502 LDOs feature thermal and adjustable voltage currentlimit protection and reverse current protection. Logic enable and error flag pins are available. • Excellent line and load regulation specifications • Logic controlled shutdown Junction temperature range of the MIC37501/02 is from –40°C to 125°C. • Thermal shutdown and current-limit protection For applications requiring input voltage greater than • Reverse-leakage protection 6.0V, see MIC3910x, MIC3915x, MIC3930x, and • Low profile S-Pak and TO-263 packages MIC3950x LDOs. Applications All support documentation can be found on Micrel’s web site at www.micrel.com. • LDO linear regulator for low-voltage digital IC • PC add-in cards • High efficiency linear power supplies • SMPS post regulator • Battery charger Typical Applications MIC37501 V = 3.0V V = 2.5V IN OUT VIN VOUT Dropout CIN VIN VOUT 100k COUT vs.OutputCurrent 100F, Ceramic 450 VEN FLG 400 GND 350 V) m 300 Fixed 2.5V Regulator with Error Flag T ( 250 2.5VOUT U MIC37502 PO 200 VIN VIN VOUT 1.3V RO 150 D 100 VIN VOUT R1 CIN COUT 50 VEN ADJ 100F, Ceramic 0 GND R2 012345 OUTPUT CURRENT (A) Adjustable Regulator Super βeta is a registered trademark of Micrel Inc. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com May 2011 1 M9999-050511-B

Micrel, Inc. MIC37501/37502 Ordering Information Part Number Output Voltage(2) Junction Temp. Range Package Standard RoHS Compliant(1) Current MIC37501-1.5BR MIC37501-1.5WR 5A 1.5V –40°C to +125°C S-Pak-7 MIC37501-1.65BR MIC37501-1.65WR 5A 1.65V –40°C to +125°C S-Pak-7 MIC37501-1.8BR MIC37501-1.8WR 5A 1.8V –40°C to +125°C S-Pak-7 MIC37501-2.5BR MIC37501-2.5WR 5A 2.5V –40°C to +125°C S-Pak-7 MIC37501-3.3BR MIC37501-3.3WR 5A 3.3V –40°C to +125°C S-Pak-7 MIC37502BR MIC37502WR 5A Adj. –40°C to +125°C S-Pak-7 MIC37502BU MIC37502WU 5A Adj. –40°C to +125°C To-263-5 Notes: 1. RoHS compliant with “high-melting solder” exemption. 2. Other Voltage available. Contact Micrel for detail. Pin Configuration 7 FLG/ADJ 5 ADJ 6 VOUT 4 VOUT 5 VOUT TAB 3 GND TAB 43 GVINND 2 VIN 2 VIN 1 EN 1 EN TO-263-5 S-PAK-7 Pin Description Pin Number Pin Number Pin Name Pin Name TO-263-5 S-PAK-7 1 1 EN Enable (input): CMOS-compatible input. Logic high = enable, logic low = shutdown. 2 2, 3 VIN Input voltage which supplies current to the output power device. Connect pins 2 and 3 together externally. 3 4 GND Ground (TAB is connected to ground). 4 5, 6 VOUT Regulator Output: Connect pins 5 and 6 together externally. — 7 FLG Error Flag (output): Open collector output. Active low indicates an output fault condition. 5 7 ADJ Adjustable regulator feedback input. Connect to resistor voltage divider. May 2011 2 M9999-050511-B

Micrel, Inc. MIC37501/37502 Absolute Maximum Ratings(1) Operating Ratings(2) Supply Voltage (V ) .................................................6.5V Supply Voltage (V ).........................................2.3V to 6.0V IN IN Enable Input Voltage (V ) .......................................6.5V Enable Input Voltage (V )..................................0V to 6.0V EN EN Power Dissipation(P ) ..........................Internally Limited Junction Temperature Range(T ).......–40°C ≤ T ≤ +125°C D J J Junction Temperature(T ) ...............–40°C ≤ T ≤ +125°C Maximum Power Dissipation.....................................Note 4 J J Storage Temperature(T ) ...............–65°C ≤ T ≤ +150°C Package Thermal Resistance S J Lead Temperature (soldering, 5 sec.) ....................260°C S-Pak(θ ).........................................................38°C/W JA ESD Rating(3)...............................................................2kV S-Pak(θ )...........................................................2°C/W JC TO-263(θ )....................................................26.2°C/W JA TO-263(θ ).........................................................2°C/W JC Electrical Characteristics(5) T = 25°C with V = V + 1V; V = V ; bold values indicate –40°C < T < +125°C; unless otherwise noted. A IN OUT EN IN J Parameter Condition Min Typ Max Units Output Voltage Accuracy IL = 10mA –1 +1 % 10mA < I < I , V + 1 ≤ V ≤ 6V –2 +2 % OUT L(max) OUT IN Output Voltage Line Regulation VIN = VOUT +1.0V to 6.0V 0.06 0.5 % Output Voltage Load Regulation IL = 10mA to 5A 0.2 1 % VIN – VOUT, Dropout Voltage(6) IL = 2.5A 350 mV IL = 5A 330 500 mV Ground Pin Current(7) IL = 5A 57 100 mA Ground Pin Current in Shutdown VIL < 0.5V, VIN = VOUT + 1V 1.0 µA Current Limit VOUT = 0 5 7.5 11 A Start-up Time VEN = VIN, IOUT = 10mA, COUT = 100µF 170 500 µs Enable Input Enable Input Threshold Regulator enable 2.25 V Regulator shutdown 0.8 V Enable Pin Input Current VIL < 0.8V (Regulator shutdown) 2 µA 4 µA VIH > 2.25V (Regulator enabled) 1 15 30 µA 75 µA Flag Output IFLG(LEAK) VOH = 6V 1 µA 2 µA VFLG(LO) VIN = 2.25V, IOL = 250µA(8) 210 400 mV 500 mV VFLG Low threshold, % of VOUT below nominal 93 % Hysteresis 2 % High threshold, % of VOUT below nominal 99.2 % MIC37502 Only Reference Voltage 1.228 1.240 1.252 V 1.215 1.265 V Adjust Pin Bias Current 40 80 nA 120 nA May 2011 3 M9999-050511-B

Micrel, Inc. MIC37501/37502 Notes: 1. Exceeding the ratings in the “Absolute Maximum Ratings” section may damage the device. 2. The device is not guaranteed to function outside its operating rating. 3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5kΩ in series with 100pF. 4. P = (T – T ) / θ , where θ depends upon the printed circuit layout. See “Applications Information” section. D(max) J(max) A JC JC 5. Specification for packaged product only 6. V = V – V when V decreased to 98% of its nominal output voltage with V = V + 1V. For output voltages below 1.75V, DO IN OUT OUT IN OUT dropout voltage specification does not apply dut to a minimum input operating voltage of 2.3V. 7. I is the quiescent current. I = I + I . GND IN GND OUT 8. For a 2.5V device, V = 2.3V (device is in dropout). IN May 2011 4 M9999-050511-B

Micrel, Inc. MIC37501/37502 Typical Characteristics Dropout Dropout DropoutCharacteristics vs.OutputCurrent vs. Temperature (1.5V) 450 500 1.6 10mAload UT (mV) 233450500000 2.5VOUT UT (mV) 440500 2.5VOUT OLTAGE (V)011...8241 DROPO 125000 DROPO 350 TPUT V00..46 5Aload 100 300 U O 50 0.2 0 250 0 012345 -40-20 02 04 06 08 0 100120 1.5 1.7 1.9 2.1 2.3 2.5 INPUT VOLTAGE (V) OUTPUT CURRENT (A) TEMPERATURE(°C) DropoutCharacteristics DropoutCharacteristics DropoutCharacteristics (1.8V) (2.5V) (3.3V) 2 3.0 3.5 10mAload 1.8 V)1.6 V) 2.5 10mAload V) 3.0 10mAload GE (1.4 GE ( 2.0 GE ( 2.5 LTA1.2 LTA 5Aload LTA 2.0 5Aload T VO0.81 5Aload T VO 1.5 T VO 1.5 U U 1.0 U P0.6 P P 1.0 T T T U0.4 U U O O 0.5 O 0.5 0.2 0 0 0 1.5 1.7 1.9 2.1 2.3 2.5 2.7 1.5 2.0 2.5 3.0 3.5 580358035803 INPUT VOLTAGE (V) 1.1.2.2.2.2.3.3.3.3.4.4. INPUT VOLTAGE (V) INPUT VOLTAGE (V) GroundCurrent GroundCurrent GroundCurrent vs.OutputCurrent vs.Suppl (1.5V) vs.Suppl (1.5V) 50 0.7 80 mA) 4405 2.5VOUT mA) 0.6 10mA mA)70 NT ( 35 NT ( 0.5 NT (60 RE 30 RE 0.4 RE50 2.5A UR 25 UR 100mA UR40 D C 20 D C 0.3 D C30 GROUN 11505 GROUN 00..12 GROUN1200 5A 0 0 0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 012345 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 OUTPUT CURRENT (A) INPUT VOLTAGE (V) INPUT VOLTAGE (V) GroundCurrent GroundCurrent GroundCurrent vs.Suppl (1.8V) vs.Suppl (1.8V) vs.Suppl (2.5V) 0.7 90 1.8 A) 0.6 10mA A) 80 A) 1.6 NT (m 0.5 NT (m 6700 NT (m 11..24 RRE 0.4 RRE 50 2.5A RRE 1.0 GROUND CU 000...123 100mA GROUND CU 12340000 5A GROUND CU 0000....2468 11000mmAA 0 0 0 012345 012345 012345 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) May 2011 5 M9999-050511-B

Micrel, Inc. MIC37501/37502 GroundCurrent GroundCurrent GroundCurrent vs.Supply(2.5V) vs.Supply(3.3V) vs.Supply(3.3V) 0.12 1.80 120 5A A)0.10 A)1.60 A)100 m m1.40 m T ( T ( T ( N0.08 N1.20 N 80 E E E R R1.00 R UR0.06 UR UR 60 ND C0.04 5A ND C00..6800 100mA ND C 40 2.5A U U U O O0.40 10mA O R0.02 2.5A R R 20 G G0.20 G 0 0 0 01234 5 01234 5 01234 5 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) GroundCurrent GroundCurrent OutputVoltage vs. Temperature vs. Temperature vs. Temperature 1 60 2.60 mA) 00..89 mA) 50 5A V) 22..5568 NT ( 0.7 100mA NT ( 40 GE ( 2.54 RE 0.6 RE TA 2.52 UR 0.5 10mA UR 30 OL 2.50 UND C 00..34 UND C 20 2.5A TPUT V 22..4468 O 0.2 O U 2.44 R R 10 O G 0.1 G 1A 2.42 0 0 2.40 -40-20 02 04 06 08 0 100120 -40-20 02 04 06 08 0 100120 -40-20 02 04 06 08 0 100120 TEMPERATURE(°C) TEMPERATURE(°C) TEMPERATURE(°C) ShortCircuitCurrent ShortCircuitCurrent vs.Suppl Voltage vs. Temperature Error Flag Pull-Up Resistor NT (A) 1890 V) 1890 56 Flag High(OK) VIN=5V CUIT CURRE 4567 T VOLTAGE ( 4567 R FLAG (V)34 R U O CI 3 P 3 R2 RT 2 OUT 2 ER FlagLow(FAULT) HO 1 1 1 S 0 0 2.25 3 3.75 4.5 5.25 6 -40-20 02 04 06 08 0 100120 0 0.01 0.1 1 10 100 1k 10k SUPPLY VOLTAGE (V) TEMPERATURE(°C) ) EnableCurrent vs. Temperature 12 A) 10 μ T( N 8 E R UR 6 C LE 4 B A EN 2 0 -40-20 02 04 06 08 0 100120 TEMPERATURE(°C) May 2011 6 M9999-050511-B

Micrel, Inc. MIC37501/37502 Functional Characteristics EnableTransient Response LineTransient Response V = 3.3V IN V = 2.5V OUT C = 100µF Ceramic OUT I = 5A OUT 5V 3.3V V = 3.3V IN V = 2.5V OUT C = 100µF Ceramic OUT LoadTransient Response LoadTransient Response V = 3.3V V = 3.3V IN IN V = 2.5V V = 2.5V OUT OUT C = 100µF Ceramic C = 100µF Ceramic OUT OUT 5A 5A 1A 100mA May 2011 7 M9999-050511-B

Micrel, Inc. MIC37501/37502 Application Information and the regulator. The low dropout properties of Micrel Super βeta PNP® regulators allow significant The MIC37501/02 is a high-performance, low dropout reductions in regulator power dissipation and the voltage regulator suitable for moderate to high-current associated heat sink without compromising regulator applications. Its 500mV dropout voltage at performance. When this technique is employed, a full load makes it especially valuable in battery- capacitor of at least 1.0µF is needed directly between powered systems and as a high-efficiency noise filter the input and regulator ground. in post-regulator applications. Unlike older NPN-pass Refer to “Application Note 9” for further details and transistor designs, where the minimum dropout examples on thermal design and heat sink voltage is limited by the based-to-emitter voltage drop applications. and collector-to-emitter saturation voltage, dropout performance of the PNP output of these devices is Output Capacitor limited only by the low VCE saturation voltage. The MIC37501/02 requires an output capacitor for A trade-off for the low dropout voltage is a varying stable operation. As a µCap LDO, the MIC37501/02 base drive requirement. Micrel’s Super βeta PNP® can operate with ceramic output capacitors as long as process reduces this drive requirement to only 2% to the amount of capacitance is 100µF or greater. For 5% of the load current. values of output capacitance lower than 100µF, the The MIC37501/02 regulator is fully protected from recommended ESR range is 200mΩ to 2Ω. The damage due to fault conditions. Current limiting is minimum value of output capacitance recommended provided. This limiting is linear; output current during for the MIC37501/02 is 47µF. overload conditions is constant. Thermal shutdown For 100µF or greater, the ESR range recommended is disables the device when the die temperature less than 1Ω. Ultra-low ESR ceramic capacitors are exceeds the maximum safe operating temperature. recommended for output capacitance of 100µF or The output structure of these regulators allows greater to help improve transient response and noise voltages in excess of the desired output voltage to be reduction at high frequency. X7R/X5R dielectric-type applied without reverse current flow. ceramic capacitors are recommended because of their temperature performance. X7Rtype capacitors Thermal Design change capacitance by 15% over their operating Linear regulators are simple to use. The most temperature range and are the most stable type of complicated design parameters to consider are ceramic capacitors. Z5U and Y5V dielectric capacitors thermal characteristics. Thermal design requires the change value by as much as 50% and 60%, following application-specific parameters: respectively, over their operating temperature ranges. • Maximum ambient temperature (T ) To use a ceramic chip capacitor with Y5V dielectric, A the value must be much higher than an X7R ceramic • Output current (I ) OUT capacitor to ensure the same minimum capacitance • Output voltage (V ) OUT over the equivalent operating temperature range. • Input voltage (V ) IN • Ground current (I ) Input Capacitor GND First, calculate the power dissipation of the regulator An input capacitor of 1.0µF or greater is recom- from these numbers and the device parameters from mended when the device is more than 4 inches away this data sheet. from the bulk supply capacitance, or when the supply is a battery. Small, surfacemount chip capacitors can PD = (VIN – VOUT) IOUT + VIN IGND be used for the bypassing. The capacitor should be where the ground current is approximated by using placed within 1" of the device for optimal performance. numbers from the “Electrical Characteristics” or Larger values will help to improve ripple rejection by “Typical Characteristics” sections. The heat sink bypassing the input to the regulator, further improving thermal resistance is then determined with this the integrity of the output voltage. formula: θSA = ((TJ(max) – TA)/ PD) – (θJC + θCS) Transient Response and 3.3V to 2.5V, 2.5V to 1.8V or 1.65V, or 2.5V to 1.5V Conversions Where TJ(max) ≤125°C and θCS is between 0°C and The MIC37501/02 has excellent transient response to 2°C/W. The heat sink may be significantly reduced in variations in input voltage and load current. The applications where the minimum input voltage is device has been designed to respond quickly to load known and is large compared with the dropout current variations and input voltage variations. Large voltage. Use a series input resistor to drop excessive output capacitors are not required to obtain this voltage and distribute the heat between this resistor performance. A standard 47µF output capacitor is all May 2011 8 M9999-050511-B

Micrel, Inc. MIC37501/37502 that is required. Larger values help to improve Enable Input performance even further. The MIC37501/02 also features an enable input for By virtue of its low dropout voltage, this device does on/off control of the device. Its shutdown state draws not saturate into dropout as readily as similar NPN- “zero” current (only microamperes of leakage). The based designs. When converting from 3.3V to 2.5V, enable input is TTL/CMOS-compatible for simple logic 2.5V to 1.8V or 1.65V, or 2.5V to 1.5V, the NPN- interface, but can be connected up to V . When IN based regulators are already operating in dropout, enabled, it draws approximately 15µA. with typical dropout requirements of 1.2V or greater. To convert down to 2.5V without operating in dropout, Adjustable Regulator Design NPN-based regulators require an input voltage of at least 3.7V. The MIC37501/02 regulator will provide excellent performance with an input as low as 3.0V or MIC37502 2.25V, respectively. This gives the PNP-based V IN OUT V IN OUT regulators a distinct advantage over older, NPN-based R1 linear regulators. ENABLE EN ADJ C SHUTDOWN OUT GND R2 Minimum Load Current The MIC37501/02 regulator is specified between finite loads. If the output current is too small, leakage ⎛ R1⎞ V =1.240V⎜1+ ⎟ currents dominate and the output voltage rises. A OUT ⎝ R2⎠ 10mA minimum load current is necessary for proper operation. Figure 2. Adjustable Regulator with Resistors Error Flag The MIC37502 allows programming the output voltage The MIC37501 features an error flag circuit that anywhere between 1.24V and the 5.5V maximum monitors the output voltage and signals an error operating rating of the family. Two resistors are used. condition when the voltage drops 5% below the Resistors can be quite large, up to 1MΩ, because of nominal output voltage. The error flag is an open- the very high input impedance and low bias current of collector output that can sink 10mA during a fault the sense comparator. condition. The resistor values are calculated by: Low output voltage can be caused by a number of ⎛V ⎞ problems, including an overcurrent fault (device in R1=R2⎜⎜ OUT −1⎟⎟ current limit) or low input voltage. The flag is ⎝1.240 ⎠ inoperative during overtemperature shutdown. Where VOUT is the desired output voltage. Figure 2 shows component definition. Applications with widely varying load currents may scale the resistors to draw the minimum load current required for proper operation (see above). May 2011 9 M9999-050511-B

Micrel, Inc. MIC37501/37502 Package Information 7-Pin S-PAK (R) θ4 θ1 θ2 θ1 θ3 θ1 θ2 θ3 θ4 1 θ 5-Pin TO-263 (U) May 2011 10 M9999-050511-B

Micrel, Inc. MIC37501/37502 MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry, specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2004 Micrel, Incorporated. May 2011 11 M9999-050511-B

Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: M icrel: MIC37501-3.3WR TR MIC37502WR TR MIC37502WU TR MIC37501-1.65WR TR M icrochip: MIC37501-1.5WR MIC37501-1.8WR MIC37502WU MIC37501-2.5WR MIC37501-3.3WR MIC37502WR MIC37501-1.65WR MIC37502WR-TR MIC37501-2.5WR-TR MIC37501-1.5WR-TR MIC37501-3.3WR-TR MIC37501- 1.65WR-TR MIC37502WU-TR MIC37501-1.8WR-TR