MIC37300/37301/37302 Micrel MIC37300/37301/37302 3.0A, Low-Voltage µCap 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 lowvoltage 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 –40°C to 125°C. 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 • • • • • LDO linear regulator for low-voltage digital IC PC add-in cards High-efficiency linear power supplies SMPS post regulator Battery charger Typical Application VIN = 3.0V MIC37302 VIN VOUT VIN MIC37300 VIN VOUT VOUT = 2.5V R1 CIN COUT 47µF, Ceramic 1.3V VEN COUT 47µF, Ceramic ADJ R2 GND GND Fixed 2.5V Regulator MIC37301 VIN VOUT CIN 100k VEN FLG Dropout vs. Output Current VOUT = 2.5V 500 450 COUT 47µF, Ceramic DROPOUT (mV) VIN = 3.0V Adjustable Regulator GND Fixed 2.5V Regulator with Error Flag 400 350 2.5VOUT 300 250 200 150 100 50 0 3.3VOUT 0 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 3 Super ßeta PNP is a registered trademark of Micrel, Inc. Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com November 2003 1 M0307-112003 MIC37300/37301/37302 Micrel Ordering Information Output Current Voltage* Junction Temp. Range Package MIC37300-1.5BR 3.0A 1.5V –40°C to +125°C S-Pak-3 MIC37300-1.65BR 3.0A 1.65V –40°C to +125°C S-Pak-3 MIC37300-1.8BR 3.0A 1.8V –40°C to +125°C S-Pak-3 MIC37300-2.5BR 3.0A 2.5V –40°C to +125°C S-Pak-3 MIC37300-3.3BR 3.0A 3.3V –40°C to +125°C S-Pak-3 MIC37301-1.5BR 3.0A 1.5V –40°C to +125°C S-Pak-5 MIC37301-1.8BR 3.0A 1.8V –40°C to +125°C S-Pak-5 MIC37301-2.5BR 3.0A 2.5V –40°C to +125°C S-Pak-5 MIC37301-3.3BR 3.0A 3.3V –40°C to +125°C S-Pak-5 MIC37302BR 3.0A ADJ. –40°C to +125°C S-Pak-5 MIC37302BU 3.0A ADJ. –40°C to +125°C TO-263-5 Part Number *For other voltages contact Micrel. Pin Configuration FLG/ADJ VOUT GND VIN EN TAB TAB 5 4 3 2 1 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. 2 1 VIN Input voltage which supplies current to the output power device. 3 2 GND Ground: TAB is connected to ground. 4 3 VOUT Regulator Output. 5 M0307-112003 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 2003 MIC37300/37301/37302 Micrel 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) ................. –40°C ≤ TJ ≤ +125°C Storage Temperature (TS) ................. –65°C ≤ TJ ≤ +150°C Lead Temperature (soldering, 5 sec.) ....................... 260°C ESD(4) Supply Voltage (VIN) ..................................... 2.25V to 6.0V Enable Input Voltage (VEN) ................................ 0V to 6.0V Junction Temperature Range (TJ) ..... –40°C ≤ TJ ≤ +125°C Package Thermal Resistance S-Pak (θJC) ........................................................ 2°C/W TO-263-5 (θJC) .................................................. 2°C/W Electrical Characteristics(5) TA = 25°C with VIN = VOUT + 1V; VEN = VIN; IL = 10mA; bold values indicate –40°C < TJ < +125°C; unless otherwise noted. Parameter Condition Min Output Voltage Accuracy IL = 10mA 10mA < IOUT < IL(max), VOUT + 1 ≤ VIN ≤ 6V Typ Max Units –1 +1 % –2 +2 % Output Voltage Line Regulation VIN = VOUT +1.0V to 6.0V, IL = 10mA 0.02 0.5 % Output Voltage Load Regulation IL = 10mA to 3A 0.2 1 % IL = 1.5A 175 350 mV IL = 3A 310 500 mV IL = 3A 27 40 50 mA mA Ground Pin Current in Shutdown VIL < 0.5V, VIN = VOUT + 1V 1.0 5 µA Current Limit VOUT = 0 4.75 6.5 A Start-up Time VEN = VIN, IOUT = 10mA, COUT = 47µF 170 500 µs VIN – VOUT; Dropout Ground Pin Voltage(6) Current(7) Enable Input Enable Input Threshold Regulator enable 2.25 V Regulator shutdown Enable Pin Input Current VIL < 0.8V (Regulator shutdown) VIH > 2.25V (Regulator enabled) 1 15 0.8 V 2 4 µA µA 30 75 µA µA 1 2 µA µA 400 500 mV mV Flag Output IFLG(LEAK) VOH = 6V VFLG(LO) VIN = 2.25V, IOL = 250µA(8) VFLG Low Threshold, % of VOUT below nominal 210 93 Hysteresis % 2 High Threshold, % of VOUT below nominal % 99.2 % 1.240 1.252 1.265 V V 40 80 120 nA nA MIC37302 Only Reference Voltage 1.228 1.215 Adjust Pin Bias Current 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) / θJA, where θJA, depends upon the printed circuit layout. See “Applications Information.” 4. Device is ESD sensitive. Handling precautions recommended. 5. Specification for packaged product only. November 2003 3 M0307-112003 MIC37300/37301/37302 Micrel Notes: 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). M0307-112003 4 November 2003 MIC37300/37301/37302 Micrel Typical Characteristics Power Supply Rejection Ratio Power Supply Rejection Ratio 80 80 VIN = 2.5V VOUT = 1.5V 70 50 40 30 50 40 30 IOUT = 3A COUT = 100µF 10 C = 0 IN 0 0.01 0.1 1 10 100 FREQUENCY (kHz) 20 20 1000 1.6 400 1.4 OUTPUT VOLTAGE (V) 350 2.5VOUT 250 200 150 100 50 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 0.8 2.5 2 3A Load 1.5 1 0.5 0.4 0 1.5 2.5 35 30 25 20 15 10 5 0.0005 GROUND CURRENT (mA) 25 20 2A 10 1A 5 November 2003 5 3.5 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 0.0003 0.0002 10mA 0.0001 0 0 3 1 2 3 4 SUPPLY VOLTAGE (V) 5 Ground Current vs. Supply Voltage (2.5V) 70 1.2 1 0.8 100mA 0.6 0.4 0.2 0 0 100mA 0.0004 1.4 3A 2 2.5 3 INPUT VOLTAGE (V) Ground Current vs. Supply Voltage (1.5V) Ground Current vs. Supply Voltage (2.5V) 35 3A Load 1 0.0006 0 40 GROUND CURRENT (mA) 1.7 1.9 2.1 2.3 INPUT VOLTAGE (V) 45 40 Ground Current vs. Supply Voltage (1.5V) 1 2 3 4 SUPPLY VOLTAGE (V) 2 0.5 3A Load 0.2 0 2 2.5 3 3.5 4 INPUT VOLTAGE (V) 3 1.5 0.6 GROUND CURRENT (mA) GROUND CURRENT (mA) OUTPUT VOLTAGE (V) 1 50 3 10mA Load 0 0 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 2.5 10mA Load 1.2 Ground Current vs. Output Current 3.5 15 0 3 10mA Load 0 1.5 Dropout Characteristics (3.3V) 30 3.3VOUT Dropout Characteristics (2.5V) GROUND CURRENT (mA) DROPOUT (mV) 450 0 1.5 150 100 50 0 1000 2.5VOUT 300 250 200 Dropout Characteristics (1.5V) Dropout vs. Temperature 300 400 350 OUTPUT VOLTAGE (V) IOUT = 3A COUT = 47µF 10 C = 0 IN 0 0.01 0.1 1 10 100 FREQUENCY (kHz) DROPOUT (mV) 60 PSRR (dB) PSRR (dB) 60 500 450 VIN = 2.5V VOUT = 1.5V 70 Dropout vs. Output Current 10mA 1 2 3 4 SUPPLY VOLTAGE (V) 5 5 60 50 40 3A 30 20 2A 10 0 0 1A 1 2 3 4 SUPPLY VOLTAGE (V) 5 M0307-112003 MIC37300/37301/37302 Micrel Ground Current vs. Supply Voltage (3.3V) 1 100mA 0.6 0.4 10mA 1 2 3 4 SUPPLY VOLTAGE (V) 2A 20 10 1A 1 2 3 4 SUPPLY VOLTAGE (V) GROUND CURRENT (mA) 2.5VOUT 8 6 4 IOUT=1.5A 2.5VOUT 35 30 25 20 15 10 5 IOUT=3A Short-Circuit Current vs. Temperature Output Voltage vs. Temperature 6 2.55 2.45 2.4 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) Flag Voltage vs. Flag Current 1.0 5 2.5VIN 4 3 2 1 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 150 100 Flag Current=250µA 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 3.3VIN 0.4 2.5VIN 0.2 FLAG CURRENT (mA) Enable Current vs. Temperature 5 4 3 2 Flag Low (FAULT) 1 VIN = 5V 0 0.01 0.1 1 10 100 1000 10000 RESISTANCE (kΩ) 6 ENABLE CURRENT (µA) FLAG VOLTAGE (V) 200 0.6 16 Flag High (OK) 250 5VIN 0 0 0.5 1 1.5 2 2.5 3 3.5 4 6 350 300 0.8 Error Flag Pull-Up Resistor 400 2.5VOUT 2.5 6 Flag Low Voltage vs. Temperature M0307-112003 IOUT=10mA 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 2.6 Short-Circuit Current vs. Supply Voltage 50 0.1 0.05 40 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 3 3.75 4.5 5.25 SUPPLY VOLTAGE (V) 0.2 0.15 5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 2.25 0.3 45 12 SHORT CIRCUIT CURRENT (A) GROUND CURRENT (mA) 30 2.5VOUT 0.25 Ground Current vs. Temperature 14 SHORT CIRCUIT CURRENT (A) 40 0 0 5 Ground Current vs. Temperature 10 3A 50 OUTPUT VOLTAGE (V) 0.2 60 0.35 FLAG VOLTAGE (V) 0.8 GROUND CURRENT (mA) 1.2 0 0 FLAG VOLTAGE (mV) 0.4 70 GROUND CURRENT (mA) GROUND CURRENT (mA) 1.4 2 Ground Current vs. Temperature Ground Current vs. Supply Voltage (3.3V) 14 12 10 8 6 4 2.5VEN 2 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) November 2003 MIC37300/37301/37302 Micrel Functional Characteristics Line Transient Response COUT = 47µF Ceramic INPUT VOLTAGE 3A 10mA COUT = 47µF Ceramic (50mV/div.) OUTPUT VOLTAGE VOUT = 2.5V 5V (2V/div.) (50mV/div.) VIN = 3.3V (3A/div.) OUTPUT CURRENT OUTPUT VOLTAGE Load Transient Response 3.3V TIME (400µs/div.) TIME (100µs/div.) Enable Transient Response OUTPUT VOLTAGE (1V/div.) ENABLE VOLTAGE (2V/div.) IOUT = 3A VIN = 3.3V COUT = 47µF 2.5V TIME (40µs/div.) November 2003 7 M0307-112003 MIC37300/37301/37302 Micrel Output Capacitor The MIC37300/01/02 requires an output capacitor for stable operation. As a µCap LDO, the MIC37300/01/02 can operate with ceramic output capacitors as long as the amount of capacitance is 47µF or greater. For values of output capacitance lower than 47µF, the recommended ESR range is 200mΩ to 2Ω. The minimum value of output capacitance recommended for the MIC37300 is 10µF. For 47µF or greater, the ESR range recommended is less than 1Ω. Ultra-low ESR, ceramic capacitors are recommended for output capacitance of 47µF 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 1.0µF 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 47µF 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. Applications Information 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 batterypowered systems and as high-efficiency noise filters in postregulator 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 ßeta 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: θSA = ((TJ(max) – TA)/ PD) – (θJC + θCS) Where TJ(max) < 125°C and θCS is between 0°C and 2°C/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 ßeta 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 1.0µF 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. M0307-112003 8 November 2003 MIC37300/37301/37302 Micrel 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 15µA. November 2003 Adjustable Regulator Design VIN MIC37302 OUT IN VOUT R1 ENABLE SHUTDOWN EN ADJ GND R2 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 1MΩ, 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). 9 M0307-112003 MIC37300/37301/37302 Micrel Package Information 0.176 ±0.005 0.405±0.005 0.065 ±0.010 20°±2° 0.060 ±0.005 0.050±0.005 0.360±0.005 0.600±0.025 SEATING PLANE 0.004 +0.004 –0.008 0.100 ±0.01 8° MAX 0.032 ±0.003 0.067±0.005 0.015 ±0.002 DIM. = INCH 5-Lead TO-263-5 (U) DIMENSIONS: INCH (MM) 0.375 (9.52) 0.365 (9.27) 0.360 (9.14) 0.350 (8.89) 0.050 (1.27) 0.030 (0.76) 0.080 (2.03) 0.070 (1.78) 0.256 BSC (6.50 BSC) 0.010 BSC (0.25 BSC) 0.316 BSC (8.03 BSC) 0.420 (10.67) 0.410 (10.41) 0.320 (8.13) 0.310 (7.87) 0.067 BSC (1.70 BSC) 0.045 (1.14) 0.035 (0.89) 0.031 (0.79) 0.025 (0.63) 0.005 (0.13) 0.001 (0.03) 0.080 (2.03) 0.070 (1.78) 0.031 (0.89) 0.041 (1.14) 0.010 BSC (0.25 BSC) 6¡ 0¡ 5-Lead S-PAK (R) M0307-112003 10 November 2003 MIC37300/37301/37302 Micrel 0.050 (1.27) 0.030 (0.76) 0.320 (8.13) 0.310 (7.87) 0.100 BSC (2.54 BSC) 0.375 (9.52) 0.365 (9.27) 0.360 (9.14) 0.350 (8.89) 0.256 BSC (6.50 BSC) 0.008 (0.20) 0.004 (0.10) 0.010 BSC (0.25 BSC) 0.316 BSC (8.03 BSC) 0.035 (0.89) 0.045 (1.14) 0.420 (0.20) 0.410 (0.10) 0.031 (0.79) 0.025 (0.63) "A" DETAIL "A" 0.420 (0.20) 0.410 (0.10) 0.080 (2.03) 0.070 (1.78) 0.041 (1.04) 0.031 (0.79) 0.010 BSC (0.25 BSC) 0.041 (1.04) 0.031 (0.79) 6¡ 0¡ 3-Lead S-PAK (R) November 2003 11 M0307-112003 MIC37300/37301/37302 Micrel MICREL, INC. TEL 1849 FORTUNE DRIVE SAN JOSE, CA 95131 + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB USA http://www.micrel.com The information furnished by Micrel in this datasheet 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 at Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2003 Micrel, Incorporated. M0307-112003 12 November 2003