MIC37300/37301/37302 Micrel, Inc. MIC37300/37301/37302 3.0A, Low-Voltage Cap LDO Regulator General Description Features The Micrel MIC37300/01/02 is a 3.0A low-dropout linear voltage regulator that provides a low-voltage, high-current output with a minimum number of external components. It offers high precision, ultra-low-dropout (500mV overtemperature), and low-ground current. The MIC37300/01/02 operates from an input of 2.25V to 6.0V. It is designed to drive digital circuits requiring low-voltage at high currents (i.e., PLDs, DSP, microcontroller, etc.). It is available in fixed and adjustable output voltages. Fixed voltages include 1.5V, 1.8V, 2.5V and 3.3V. The adjustable version is capable of 1.24V to 5.5V. Features of the MIC37300/01/02 LDO include thermal and current-limit protection, and reverse-current protection. Logic enable and error flag pins are available on the 5-pin version. Junction temperature range of the MIC37300/01/02 is from -40C to 125C. For applications requiring input voltage greater than 6.0V, see the MIC3910x, MIC3915x, MIC3930x, and MIC3950x LDOs. All data sheets and support documentation can be found on Micrel's web site at www.micrel.com. * 3.0A minimum guaranteed output current * 500mV maximum dropout-voltage overtemperature Ideal for 3.0V to 2.5V conversion Ideal for 2.5V to 1.8V, 1.65V, or 1.5V conversion * Stable with ceramic or tantalum capacitor * Wide input voltage range: VIN: 2.25V to 6.0V * +1.0% initial output tolerance * Fixed and adjustable output voltages: MIC37300 -- 3-pin fixed MIC37301 -- 5-pin fixed with flag MIC37302 -- 5-pin adjustable * Excellent line and load regulation specifications * Logic controlled shutdown * Thermal shutdown and current-limit protection * Reverse-leakage protection * Low profile S-Pak package Applications * * * * * Typical Application VIN = 3.0V MIC37302 VIN VOUT VIN MIC37300 VIN LDO linear regulator for low-voltage digital IC PC add-in cards High-efficiency linear power supplies SMPS post regulator Battery charger VOUT R1 CIN VOUT = 2.5V 1.3V VEN ADJ R2 GND COUT 47F, Ceramic COUT 47F, Ceramic GND Adjustable Regulator Fixed 2.5V Regulator MIC37301 VIN VOUT = 2.5V VOUT CIN 100k VEN FLG DROPOUT (mV) VIN = 3.0V COUT 47F, Ceramic GND Fixed 2.5V Regulator with Error Flag 500 450 400 350 300 250 200 150 100 50 0 Dropout vs. Output Current 2.5VOUT 3.3VOUT 0 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 3 Super eta PNP 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 November 2005 1 M9999-110305 MIC37300/37301/37302 Micrel, Inc. Ordering Information Part Number Voltage** Junction Temp. Range Package 3.0A 1.5V -40C to +125C S-Pak-3 3.0A 1.65V -40C to +125C S-Pak-3 MIC37300-1.8WR 3.0A 1.8V -40C to +125C S-Pak-3 MIC37300-2.5BR MIC37300-2.5WR 3.0A 2.5V -40C to +125C S-Pak-3 MIC37300-3.3BR MIC37300-3.3WR 3.0A 3.3V -40C to +125C S-Pak-3 MIC37301-1.5BR MIC37301-1.5WR 3.0A 1.5V -40C to +125C S-Pak-5 MIC3730-1.8BR MIC3730-1.8WR 3.0A 1.8V -40C to +125C S-Pak-5 MIC37301-2.5BR MIC37301-2.5WR 3.0A 2.5V -40C to +125C S-Pak-5 MIC37301-3.3BR MIC37301-3.3WR 3.0A 3.3V -40C to +125C S-Pak-5 MIC37302BR MIC37302WR 3.0A ADJ -40C to +125C S-Pak-5 MIC37302BU MIC37302WU 3.0A ADJ -40C to +125C TO-263-5 Standard RoHS Compliant* MIC37300-1.5BR MIC37300-1.5WR MIC37300-1.65BR MIC37300-1.65WR MIC37300-1.8BR Output Current *RoHS Compliant with 'high-melting solder' exemption. **Other voltages available. Contact Micrel for details. Pin Configuration 5 4 3 2 1 FLG/ADJ VOUT GND VIN EN S-PAK-5 (R) TO-263-5 (U) 3 VOUT 2 GND 1 VIN S-PAK-3 (R) Pin Description Pin Number TO-263-5 S-PAK-5 Pin Number S-PAK-3 1 Pin Name Pin Function EN Enable (Input): CMOS compatible input. Logic high = enable, logic low = shutdown. VIN Input voltage which supplies current to the output power device. 2 1 3 2 GND Ground: TAB is connected to ground. 4 3 VOUT Regulator Output. 5 M9999-110305 FLG Error Flag (Output): Open collector output. Active-low indicates an output fault condition. ADJ Adjustable Regulator Feedback Input: Connect to resistor voltage divider. 2 November 2005 MIC37300/37301/37302 Micrel, Inc. Absolute Maximum Rating(1) Operating Maximum Rating(2) Supply Voltage (VIN) ..................................................... 6.5V Enable Input Voltage (VEN)(3) ....................................... 6.5V Power Dissipation (PD)(3) ......................... Internally Limited Junction Temperature (TJ) .................. -40C TJ +125C Storage Temperature (TS) .................. -65C TJ +150C Lead Temperature (soldering, 5 sec.) ........................ 260C ESD(4) Supply Voltage (VIN) .......................................2.25V to 6.0V Enable Input Voltage (VEN) .................................0V to 6.0V Junction Temperature Range (TJ) ...... -40C TJ +125C Package Thermal Resistance S-Pak (JC) ....................................................... 2C/W TO-263-5 (JC) .................................................. 2C/W Electrical Characteristics(5) TA = 25C with VIN = VOUT + 1V; VEN = VIN; IL = 10mA; bold values indicate -40C < TJ < +125C; unless otherwise noted. Parameter Condition Output Voltage Accuracy IL = 10mA Output Voltage Line Regulation Output Voltage Load Regulation VIN - VOUT; Dropout Voltage(6) Ground Pin Current(7) Ground Pin Current in Shutdown Current Limit Start-up Time Enable Input Enable Input Threshold Min 10mA < IOUT < IL(max), VOUT + 1 VIN 6V Typ Max Units -1 +1 % -2 +2 % VIN = VOUT +1.0V to 6.0V, IL = 10mA 0.02 0.5 % 0.2 1 % IL = 1.5A IL = 10mA to 3A 175 350 mV IL = 3A 310 500 mV IL = 3A 27 40 50 mA mA VIL < 0.5V, VIN = VOUT + 1V 1.0 5 A VOUT = 0 VEN = VIN, IOUT = 10mA, COUT = 47F 4.75 6.5 A 170 500 s 2.25 Regulator enable V Regulator shutdown Enable Pin Input Current VIL < 0.8V (Regulator shutdown) VIH > 2.25V (Regulator enabled) 1 15 0.8 V 2 4 A A 30 75 A A 1 2 A A 400 500 mV mV Flag Output IFLG(LEAK) VOH = 6V VFLG(LO) VIN = 2.25V, IOL = 250A(8) VFLG Low Threshold, % of VOUT below nominal MIC37302 Only 210 93 Hysteresis % 2 High Threshold, % of VOUT below nominal Reference Voltage 1.228 1.215 Adjust Pin Bias Current % 99.2 % 1.240 1.252 1.265 V V 40 80 120 nA nA Notes: 1. Exceeding the absolute maximum ratings may damage the device. 2. The device is not guaranteed to function outside its operating rating. 3. PD(max) = (TJ(max) - TA) / JA, where JA, depends upon the printed circuit layout. See "Applications Information." 4. Device is ESD sensitive. Handling precautions recommended. 5. Specification for packaged product only. 6. VDO = VIN - VOUT when VOUT decreased to 98% of its nominal output voltage with VIN = VOUT +1V. For output voltages below 1.75V, dropout voltage specification does not apply due to a minimum input operating voltage of 2.25V. 7. IGND is the quiescent current. IIN = IGND + IOUT. 8. For a 2.5V device, VIN = 2.250V (device is in dropout). November 2005 3 M9999-110305 MIC37300/37301/37302 Micrel, Inc. Typical Characteristics 80 VIN = 2.5V VOUT = 1.5V 70 60 60 50 50 40 40 30 30 I = 3A 20 OUT COUT = 47F 10 C = 0 IN 0 0.01 0.1 1 10 100 FREQUENCY (kHz) 1000 1.6 400 1.4 OUTPUT VOLTAGE (V) 350 300 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE(C) 3 10mA Load 2.5 2 3A Load 1.5 1 0.5 0 1.5 Ground Current vs. Supply Voltage (1.5V) 30 3A 25 20 2A 15 10 1A 5 0 0 1 2 3 4 SUPPLY VOLTAGE (V) M9999-110305 0 1.4 35 GROUND CURRENT (mA) GROUND CURRENT (mA) 2 2.5 3 3.5 4 INPUT VOLTAGE (V) 5 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 100mA 0.6 0.4 0.2 10mA 1 2 3 4 SUPPLY VOLTAGE (V) 4 5 3.5 Ground Current vs. Supply Voltage (1.5V) 100mA 0.0003 0.0002 10mA 0.0001 0 0 70 1 2 2.5 3 INPUT VOLTAGE (V) 0.0004 Ground Current vs. Supply Voltage (2.5V) 0.8 3A Load 1 0.0005 3 1.2 0 0 2 0.0006 45 40 35 30 25 20 15 10 5 0 3 Dropout Characteristics (2.5V) 0 1.5 2.5 GROUND CURRENT (mA) GROUND CURRENT (mA) OUTPUT VOLTAGE (V) 3.5 1.7 1.9 2.1 2.3 INPUT VOLTAGE (V) Ground Current vs. Output Current 50 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 0.5 3A Load 0 1.5 Dropout Characteristics (3.3V) 0 1.5 0.2 50 40 1 0.4 100 3.3VOUT 2.5 10mA Load 0.6 150 2.5VOUT 3 10mA Load 0.8 200 200 150 100 50 0 Dropout Characteristics (1.5V) 1.2 2.5VOUT 250 1000 Dropout vs. Output Current 500 450 400 350 300 250 GROUND CURRENT (mA) DROPOUT (mV) I = 3A 20 OUT COUT = 100F 10 C = 0 IN 0 0.01 0.1 1 10 100 FREQUENCY (kHz) Dropout vs. Temperature 450 VIN = 2.5V VOUT = 1.5V 70 DROPOUT (mV) 80 Power Supply Rejection Ratio OUTPUT VOLTAGE (V) Power Supply Rejection Ratio 1 2 3 4 SUPPLY VOLTAGE (V) 5 Ground Current vs. Supply Voltage (2.5V) 60 50 40 3A 30 20 2A 10 0 0 1A 1 2 3 4 SUPPLY VOLTAGE (V) 5 November 2005 MIC37300/37301/37302 1 2 3 4 SUPPLY VOLTAGE (V) 2.5VOUT 6 4 2 IOUT=1.5A 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 400 10 30 25 20 15 10 Flag Low Voltage vs. Temperature FLAG VOLTAGE (V) 200 150 100 50 Flag Current =250A 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) November 2005 IOUT=3A IOUT=10mA 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE(C) 2.6 4 3 2 1 2.5VOUT 2.5 2.45 2.4 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 1.0 5 2.5VIN Output Voltage vs. Temperature 2.55 Short-Circuit Current vs. Temperature 6 0.8 Flag Voltage vs. Flag Current 5VIN 0.6 3.3VIN 0.4 0.2 2.5VIN 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 0 0 0.5 1 1.5 2 2.5 3 3.5 4 FLAG CURRENT (mA) Error Flag Pull-Up Resistor Enable Current vs. Temperature 6 350 250 0.1 0.05 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE(C) 6 300 0.2 0.15 5 2.5VOUT 35 5 0.3 Ground Current vs. Temperature 40 Short-Circuit Current vs. Supply Voltage 3 3.75 4.5 5.25 SUPPLY VOLTAGE (V) 1A 1 2 3 4 SUPPLY VOLTAGE (V) 45 8 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 2.25 2A 20 5 12 10 30 0 0 Ground Current vs. Temperature GROUND CURRENT (mA) 10mA 40 2.5VOUT 0.25 FLAG VOLTAGE (V) 0.2 3A 50 Ground Current vs. Temperature 0.35 F lag High (OK ) 5 4 3 2 1 0 F lag Low (FAULT) VIN = 5V 0.01 0.1 1 10 100 1000 10000 RESISTANCE (k) 5 16 ENABLE CURRENT (A) 0.4 0.4 60 SHORT CIRCUIT CURRENT (A) GROUND CURRENT (mA) 100mA 0.6 14 SHORT CIRCUIT CURRENT (A) GROUND CURRENT (mA) 1 0 0 FLAG VOLTAGE (mV) 70 1.2 0.8 Ground Current vs. Supply Voltage (3.3V) OUTPUT VOLTAGE (V) Ground Current vs. Supply Voltage (3.3V) GROUND CURRENT (mA) GROUND CURRENT (mA) 1.4 Micrel, Inc. 14 12 10 8 6 4 2.5VE N 2 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) M9999-110305 MIC37300/37301/37302 Micrel, Inc. Functional Characteristics Line Transient Response OUTPUT VOL AGE (50mV/div.) VIN = 3.3V VOUT = 2.5V COUT = 47F Ceramic COUT = 47F Ceramic 5V INPUT VOL AGE (2V/div.) 3A OUTPUT CURRENT (3A/div.) OUTPUT VOL AGE (50mV/div.) Load Transient Response 10mA 3.3V ENABLE VOL AGE OUTPUT VOL AGE (2V/div.) (1V/div.) Enable Transient Response M9999-110305 IOUT = 3A VIN = 3.3V COUT = 47F 2.5V 6 November 2005 MIC37300/37301/37302 Micrel, Inc. Applications Information Output Capacitor The MIC37300/01/02 requires an output capacitor for stable operation. As a Cap LDO, the MIC37300/01/02 can operate with ceramic output capacitors as long as the amount of capacitance is 47F or greater. For values of output capacitance lower than 47F, the recommended ESR range is 200m to 2. The minimum value of output capacitance recommended for the MIC37300 is 10F. For 47F or greater, the ESR range recommended is less than 1. Ultra-low ESR, ceramic capacitors are recommended for output capacitance of 47F or greater to help improve transient response and noise reduction at high frequency. X7R/X5R dielectric-type ceramic capacitors are recommended because of their temperature performance. X7R-type capacitors change capacitance by 15% over their operating temperature range and are the most stable type of ceramic capacitors. Z5U and Y5V dielectric capacitors change value by as much as 50% and 60%, respectively, over their operating temperature ranges. To use a ceramic chip capacitor with Y5V dielectric, the value must be much higher than an X7R ceramic capacitor to ensure the same minimum capacitance over the equivalent operating temperature range. Input Capacitor An input capacitor of 1.0F or greater is recommended when the device is more than 4 inches away from the bulk supply capacitance, or when the supply is a battery. Small, surfacemount chip capacitors can be used for the bypassing. The capacitor should be place within 1" of the device for optimal performance. 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 2.5V, 2.5V to 1.8V or 1.65V, or 2.5V to 1.5V Conversions The MIC37300/01/02 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 47F output capacitor, preferably tantalum, is all that is required. Larger values help to improve performance even further. By virtue of its low-dropout voltage, this device does not saturate into dropout as readily as similar NPN-based designs. When converting from 3.3V to 2.5V, 2.5V to 1.8V or 1.65V, or 2.5V to 1.5V, the NPN-based regulators are already operating in dropout, with typical dropout requirements of 1.2V or greater. To convert down to 2.5V without operating in dropout, NPN-based regulators require an input voltage of 3.7V at the very least. The MIC37300/01/02 regulator will provide excellent performance with an input as low as 3.0V or 2.25V, respectively. This gives the PNP-based regulators a distinct advantage over older, NPN-based linear regulators. The MIC37300/01/02 is a high-performance low-dropout voltage regulator suitable for moderate to high-current regulator applications. Its 500mV dropout voltage at full load and overtemperature makes it especially valuable in battery-powered systems and as high-efficiency noise filters in post-regulator applications. Unlike older NPN-pass transistor designs, there the minimum dropout voltage is limited by the based-to-emitter voltage drop and collector-to-emitter saturation voltage, dropout performance of the PNP output of these devices is limited only by the low VCE saturation voltage. A trade-off for the low dropout voltage is a varying base drive requirement. Micrel's Super eta PNP process reduces this drive requirement to only 2% to 5% of the load current. The MIC37300/01/02 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. The output structure of these regulators allows voltages in excess of the desired output voltage to be applied without reverse current flow. Thermal Design Linear regulators are simple to use. The most complicated design parameters to consider are thermal characteristics. Thermal design requires the following application-specific parameters: * Maximum ambient temperature (TA) * Output current (IOUT) * Output voltage (VOUT) * Input voltage (VIN) * Ground current (IGND) First, calculate the power dissipation of the regulator from these numbers and the device parameters from this datasheet. PD = (VIN - VOUT) IOUT + VIN IGND where the ground current is approximated by using numbers from the "Electrical Characteristics" or "Typical Characteristics." Then the heat sink thermal resistance is determined with this formula: SA = ((TJ(max) - TA)/ PD) - (JC + CS) Where TJ(max) < 125C and CS is between 0C and 2C/W. 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 Micrel's Super eta 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 1.0F is needed directly between the input and regulator ground. Refer to "Application Note 9" for further details and examples on thermal design and heat sink applications. November 2005 7 M9999-110305 MIC37300/37301/37302 Micrel, Inc. Minimum Load Current The MIC37300/01/02 regulator is specified between finite loads. If the output current is too small, leakage currents dominate and the output voltage rises. A 10mA minimum load current is necessary for proper operation. Error Flag The MIC37301 features an error flag circuit that monitors the output voltage and signals an error condition when the voltage is 5% below the nominal output voltage. The error flag is an open-collector output that can sink 10mA 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. Enable Input The MIC37301/37302 also features an enable input for on/off control of the device. Its shutdown state draws "zero" current (only microamperes of leakage). The enable input is TTL/CMOS compatible for simple logic interface, but can be connected up to VIN. When enabled, it draws approximately 15A. M9999-110305 Adjustable Regulator Design VIN ENABLE SHUTDOWN MIC37302 IN OUT EN ADJ GND R1 R2 VOUT COUT R1 VOUT = 1.240V 1 + R2 Figure 2. Adjustable Regulator with Resistors The MIC37302 allows programming the output voltage anywhere between 1.24V and the 5.5V maximum operating rating of the family. Two resistors are used. Resistors can be quite large, up to 1M, because of the very high input impedance and low bias current of the sense comparator. The resistor values are calculated by: V R1 = R2 OUT - 1 1.240 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). 8 November 2005 MIC37300/37301/37302 Micrel, Inc. Package Information 4 1 2 1 1 2 3 4 1 3 5-Pin TO-263-5 (U) 5-Pin S-PAK (R) November 2005 9 M9999-110305 MIC37300/37301/37302 Micrel, Inc. 3-Pin S-PAK (R) 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 This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. 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. (c) 2002 Micrel, Inc. M9999-110305 10 November 2005