MIC39150/39151 Micrel MIC39150/39151 1.5A Low-Voltage Low-Dropout Regulator General Description Features The MIC39150 and MIC39151 are 1.5A low-dropout linear voltage regulators that provide a low voltage, high current output with a minimum of external components. Utilizing Micrel’s proprietary Super βeta PNP™ pass element, the MIC39150/1 offers extremely low dropout (typically 375mV at 1.5A) and low ground current (typically 17mA at 1.5A). The MIC39150/1 is ideal for PC add-in cards that need to convert from 3.3V to 2.5V or 2.5V to 1.8V. A guaranteed maximum dropout voltage of 500mV over all operating conditions allows the MIC39150/1 to provide 2.5V from a supply as low as 3V or 1.8V from a supply as low as 2.3V. The MIC39150/1 also has fast transient response for heavy switching applications. This device requires only 10µF of output capacitance to maintain stability and achieve fast transient response The MIC39150/1 is fully protected with overcurrent limiting, thermal shutdown, reversed-battery protection, reversedlead insertion, and reverse-leakage protection. The MIC39151 offers a TTL-logic compatible enable pin and an error flag that indicates undervoltage and over current conditions. Offered in fixed voltages of 2.5V and 1.8V, the MIC39150/1 comes in the TO-220 and TO-263 packages and is an ideal upgrade to older, NPN-based linear voltage regulators. • 1.5A minimum guaranteed output current • 500mV maximum dropout voltage over temperature Ideal for 3.0V to 2.5V conversion Ideal for 2.5 to 1.8V conversion • 1% initial accuracy • Low ground current • Current limiting and Thermal shutdown • Reversed-battery and reversed lead insertion protection • Reversed-leakage protection • Fast transient response • TO-263 and TO-220 packaging • TTL/CMOS compatible enable pin (MIC39151 only) • Error flag output (MIC39151 only) Applications • • • • • • Low-voltage digital ICs LDO linear regulator for PC add-in cards High-efficiency linear power supplies SMPS post regulator Low-voltage microcontrollers StrongARM™ processor supply For applications requiring input voltage greater than 16V or automotive load dump protection, see the MIC29150/1/2/3 family. Typical Application 100kΩ MIC39150-2.5 VIN 3.3V IN OUT GND MIC39151-2.5 VOUT 2.5V ENABLE SHUTDOWN VIN 3.3V 10µF tantalum EN FLG ERROR FLAG OUTPUT IN OUT VOUT 2.5V GND 10µF tantalum MIC39150 MIC39151 StrongARM is a trademark of Advanced RSIC Machines, Ltd. Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com May 2000 1 MIC39150/39151 MIC39150/39151 Micrel Ordering Information Part Number Voltage Temperature Range Package MIC39150-1.8BT 1.8V –40°C to +125°C 3-lead TO-220 MIC39150-1.8BU 1.8V –40°C to +125°C 3-lead TO-263 MIC39151-1.8BT 1.8V –40°C to +125°C 5-lead TO-220 MIC39151-1.8BU 1.8V –40°C to +125°C 5-lead TO-263 MIC39150-2.5BT 2.5V –40°C to +125°C 3-lead TO-220 MIC39150-2.5BU 2.5V –40°C to +125°C 3-lead TO-263 MIC39151-2.5BT 2.5V –40°C to +125°C 5-lead TO-220 MIC39151-2.5BU 2.5V –40°C to +125°C 5-lead TO-263 * order note & V 3 OUT 2 GND 1 IN TAB TAB Pin Configuration MIC39150-x.xBT TO-220-3 (T) OUT 2 GND 1 IN MIC39150-x.xBU TO-263-3 (U) FLG OUT GND IN EN 5 4 3 2 1 TAB 5 4 3 2 1 TAB 3 FLG OUT GND IN EN MIC39151-x.xBU TO-263-5 (U) MIC39151-x.xBT TO-220-5 (T) Pin Description Pin Number MIC39150 Pin Number MIC39151 Pin Name 1 EN Enable (Input): TTL/CMOS compatible input. Logic high = enable; logic low or open = shutdown 1 2 IN Unregulated Input: +16V maximum supply. 2, TAB 3, TAB GND Ground: Ground pin and TAB are internally connected. 3 4 OUT Regulator Output 5 FLG Error Flag (Ouput): Open-collector output. Active low indicates an output fault condition. MIC39150/39151 Pin Function 2 May 2000 MIC39150/39151 Micrel Absolute Maximum Ratings (Note 1) Operating Ratings (Note 2) Supply Voltage (VIN) ..................................... –20V to +20V Enable Voltage (VEN) .................................................. +20V Storage Temperature (TS) ....................... –65°C to +150°C Lead Temperature (soldering, 5 sec.) ....................... 260°C ESD, Note 3 Supply Voltage (VIN) .................................. +2.25V to +16V Enable Voltage (VEN) .................................................. +16V Maximum Power Dissipation (PD(max))..................... Note 4 Junction Temperature (TJ) ....................... –40°C to +125°C Package Thermal Resistance TO-263 (θJC) ......................................................... 2°C/W TO-220 (θJC) ......................................................... 2°C/W Electrical Characteristics VIN = VOUT +1V; VEN = 2.4V; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted Symbol Parameter Condition VOUT Output Voltage 10mA 10mA ≤ IOUT ≤ 1.5A, VOUT + 1V ≤ VIN ≤ 8V Line Regulation IOUT = 10mA, VOUT + 1V ≤ VIN ≤ 16V Load Regulation VIN = VOUT + 1V, 10mA ≤ IOUT ≤ 1.5A, ∆VOUT/∆T Output Voltage Temp. Coefficient, Note 5 VDO Dropout Voltage, Note 6 IGND Ground Current, Note 7 Min Typ Max Units 1 2 % % 0.06 0.5 % 0.2 1 % 20 100 ppm/°C IOUT = 100mA, ∆VOUT = –1% 80 200 mV IOUT = 750mA, ∆VOUT = –1% 260 IOUT = 1.5A, ∆VOUT = –1% 375 500 mV IOUT = 750mA, VIN = VOUT + 1V 4 20 mA IOUT = 1.5A, VIN = VOUT + 1V 17 mA –1 –2 mV IGND(do) Dropout Ground Pin Current VIN ≤ VOUT(nominal) – 0.5V, IOUT = 10mA 1.1 mA IOUT(lim) Current Limit VOUT = 0V, VIN = VOUT + 1V 2.8 A IOUT(min) Minimum Load Current 7 10 mA 0.8 V Enable Input (MIC39151) VEN Enable Input Voltage logic low (off) logic high (on) IIN Enable Input Current VEN = 2.25V 2.25 1 V 30 75 µA µA 2 4 µA µA 10 20 µA 15 VEN = 0.8V IOUT(shdn) Shutdown Output Current Note 8 Flag Output (MIC39151) IFLG(leak) Output Leakage Current VOH = 16V 0.01 1 2 µA µA VFLG(do) Output Low Voltage VIN = 2.250V, IOL, = 250µA, Note 9 180 300 400 mV mV VFLG Low Threshold % of VOUT High Threshold % of VOUT 93 99.2 Hysteresis May 2000 % 1 3 % % MIC39150/39151 MIC39150/39151 Micrel Note 1. Exceeding the absolute maximum ratings may damage the device. Note 2. The device is not guaranteed to function outside its operating rating. Note 3. Devices are ESD sensitive. Handling precautions recommended. Note 4. PD(max) = (TJ(max) – TA) ÷ θJA, where θJA depends upon the printed circuit layout. See “Applications Information.” Note 5. Output voltage temperature coefficient is ∆VOUT(worst case) ÷ (TJ(max) – TJ(min)) where TJ(max) is +125°C and TJ(min) is –40°C. Note 6. VDO = VIN – VOUT when VOUT decreases to 98% of its nominal output voltage with VIN = VOUT + 1V. For output voltages below 2.25V, dropout voltage is the input-to-output voltage differential with the minimum input voltage being 2.25V. Minimum input operating voltage is 2.25V. Note 7. IGND is the quiescent current. IIN = IGND + IOUT. Note 8. VEN ≤ 0.8V, VIN ≤ 8V, and VOUT = 0V. Note 9. For a 2.5V device, VIN = 2.250V (device is in dropout). MIC39150/39151 4 May 2000 MIC39150/39151 Micrel Typical Characteristics VIN = 3.3V VOUT = 2.5V 30 20 20 ILOAD = 1.5A COUT = 47µF CIN = 0 10 Dropout Voltage vs. Temperature 200 ILOAD = 1.5A 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) ILOAD = 100mA 2.2 2.0 1.8 ILOAD = 1.5A 1.6 ILOAD = 750mA 1.4 1.2 0.6 0.4 0.2 GROUND CURRENT (mA) ILOAD = 10mA 0 2 4 6 8 10 SUPPLY VOLTAGE (V) 12 Ground Current vs. Temperature 7 6 VOUT = 2.5V 5 VOUT = 1.8V 3 2 1 ILOAD = 750mA 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) May 2000 25 ILOAD = 1500mA ILOAD = 1000mA ILOAD = 750mA 0 2 4 6 8 10 SUPPLY VOLTAGE (V) 12 5 VOUT = 2.5V VOUT = 2.5V 15 VOUT = 1.8V 10 ILOAD = 1.5A 5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 5 0 250 500 750 1000 1250 1500 OUTPUT CURRENT (mA) Ground Current vs. Temperature 0.35 0.34 VOUT = 1.8V 0.33 0.32 V = 2.5V OUT 0.31 ILOAD = 10mA 0.30 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) Ground Current vs. Temperature 20 VOUT = 1.8V 10 0.36 GROUND CURRENT (mA) 0.8 65 60 55 50 45 40 35 30 25 20 15 10 5 0 SHORT CIRCUIT CURRENT (A) GROUND CURRENT (mA) ILOAD = 100mA 1.0 15 INPUT VOLTAGE (V) GROUND CURRENT (mA) GROUND CURRENT (mA) 1.4 20 0 Ground Current vs. Supply Voltage 1.6 500 1000 1500 OUTPUT CURRENT (mA) 25 2.4 1.8 1.2 0 Ground Current vs. Output Current 2.6 Ground Current vs. Supply Voltage 4 0 GROUND CURRENT (mA) VOUT = 2.5V 100 VOUT = 2.5V 100 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 VOUT = 1.8V 300 8 200 2.8 400 VOUT = 1.8V 300 Dropout Characteristics 500 0.0 400 0 1E+1 1k 1E+4 10k 1E+5 1M 10 1E+2 100k 1E+6 100 1E+3 FREQUENCY (Hz) OUTPUT VOLTAGE (V) DROPOUT VOLTAGE (mV) VIN = 3.3V VOUT = 2.5V 30 ILOAD = 1.5A 10 COUT = 10µF CIN = 0 0 1E+1 1k 1E+4 10k 1E+5 1M 10 1E+2 100k 1E+6 100 1E+3 FREQUENCY (Hz) 600 Dropout Voltage vs. Output Current 500 40 40 PSRR (dB) PSRR (dB) 50 Power Supply Rejection Ratio 50 DROPOUT VOLTAGE (mV) Power Supply Rejection Ratio 60 3.5 3.0 2.5 Short Circuit vs. Temperature typical 2.5V device typical 1.8V device 2.0 1.5 1.0 0.5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) MIC39150/39151 MIC39150/39151 Error Flag Pull-Up Resistor 12 ENABLE CURRENT µA) FLAG VOLTAGE (V) VIN = 5V 5 4 FLAG HIGH (OK) 3 2 FLAG LOW (FAULT) 1 0 0.01 0.1 10 Enable Current vs. Temperature 250 VIN = VOUT + 1V VEN = 2.4V FLAG VOLTAGE (mV) 6 Micrel 8 6 4 2 0 -40 -20 0 20 40 60 80 100120140 TEMPERATURE (°C) 1 10 100 100010000 RESISTANCE (kΩ) 200 Flag-Low Voltage vs. Temperature FLAG-LOW VOLTAGE 150 100 VIN = 2.25V RPULL-UP = 22kΩ 50 0 -40 -20 0 20 40 60 80 100120140 TEMPERATURE (°C) Functional Characteristics OUTPUT VOLTAGE (500mV/div.) Load Transient Response VIN = 3.3V VOUT = 2.5V COUT = 10µF VIN = 3.3V VOUT = 2.5V COUT = 47µF 1.5A LOAD CURRENT (500mA/div.) 1.5A LOAD CURRENT (500mA/div.) OUTPUT VOLTAGE (500mV/div.) Load Transient Response 100mA TIME (250µs/div.) 10mA TIME (250µs/div.) OUTPUT VOLTAGE (50mV/div.) Load Transient Response VOUT = 2.5V COUT = 10µF ILOAD = 10mA 5V INPUT VOLTAGE (2V/div.) 3.3V TIME (500µs/div.) MIC39150/39151 6 May 2000 MIC39150/39151 Micrel Functional Diagram OUT IN O.V. ILIMIT 1.180V FLAG* Ref. 18V 1.240V EN* Thermal Shutdown GND * MIC39151 only May 2000 7 MIC39150/39151 MIC39150/39151 Micrel 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 Super βeta 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 1µF 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 specification. Output Capacitor The MIC39150/1 requires an output capacitor to maintain stability and improve transient response. Proper capacitor selection is important to ensure proper operation. The MIC39150/1 output capacitor selection is dependent upon the ESR (equivalent series resistance) of the output capacitor to maintain stability. When the output capacitor is 10µF or greater, the output capacitor should have an ESR less than 2Ω. This will improve transient response as well as promote stability. Ultralow ESR capacitors (<100mΩ), such as ceramic chip capacitors may promote instability. These very low ESR levels may cause an oscillation and/or underdamped transient response. A low-ESR 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 < 2Ω. The value of the output capacitor can be increased without limit. Higher capacitance values help to improve transient response and ripple rejection and reduce output noise. Input Capacitor An input capacitor of 1µF or greater is recommended when the device is more than 4 inches away from the bulk ac supply capacitance, or when the supply is a battery. Small, surfacemount, ceramic chip capacitors can be used for the bypassing. The capacitor should be placed 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 or 2.5V to 1.8V Conversion The MIC39150/1 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 10µF 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, or 2.5V to 1.8V, 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 MIC39150/1 regulator will provide excellent performance with an input as low as 3.0V or 2.5V, respectively. This gives Applications Information The MIC39150/1 is a high-performance low-dropout voltage regulator suitable for moderate to high-current voltage 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, where the minimum dropout voltage is limited by the base-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 βeta PNP™ process reduces this drive requirement to only 2% to 5% of the load current. The MIC39150/1 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. VIN MIC39150-x.x IN VOUT OUT GND CIN COUT Figure 1. Capacitor Requirements 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 ( − θ JC + θCS ) Where TJ (max) ≤ 125°C and θCS is between 0° and 2°C/W. The heat sink may be significantly reduced in applications where the minimum input voltage is known and is large MIC39150/39151 8 May 2000 MIC39150/39151 Micrel the PNP-based regulators a distinct advantage over older, NPN-based linear regulators. Minimum Load Current The MIC39150 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 regulation. Error Flag The MIC39151 version features an error flag circuit which monitors the output voltage and signals an error condition when the voltage 5% below the nominal output voltage. The error flag is an open-collector output that can sink 10mA during a fault condition. May 2000 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 MIC39151 version 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 to up to 20V. When enabled, it draws approximately 15µA. 9 MIC39150/39151 MIC39150/39151 Micrel Package Information 0.151 D ±0.005 (3.84 D ±0.13) 0.410 ±0.010 (10.41 ±0.25) 0.108 ±0.005 (2.74 ±0.13) 0.176 ±0.005 (4.47 ±0.13) 0.590 ±0.005 (14.99 ±0.13) 0.818 ±0.005 (20.78 ±0.13) 0.050 ±0.005 (1.27 ±0.13) 7° 0.356 ±0.005 (9.04 ±0.13) 3° 7° 1.140 ±0.010 (28.96 ±0.25) 0.050 ±0.003 (1.27 ±.08) 0.030 ±0.003 (0.76 ±0.08) 0.100 ±0.020 (2.54 ±0.51) 0.018 ±0.008 (0.46 ±0.020) 0.100 ±0.005 (2.54 ±0.13) DIMENSIONS: INCH (MM) 3-Lead TO-220 (T) 0.150 D ±0.005 (3.81 D ±0.13) 0.177 ±0.008 (4.50 ±0.20) 0.400 ±0.015 (10.16 ±0.38) 0.108 ±0.005 (2.74 ±0.13) 0.050 ±0.005 (1.27 ±0.13) 0.241 ±0.017 (6.12 ±0.43) 0.578 ±0.018 (14.68 ±0.46) SEATING PLANE 7° Typ. 0.550 ±0.010 (13.97 ±0.25) 0.067 ±0.005 (1.70 ±0.127) 0.032 ±0.005 (0.81 ±0.13) 0.268 REF (6.81 REF) 0.018 ±0.008 (0.46 ±0.20) 0.103 ±0.013 (2.62±0.33) Dimensions: inch (mm) 5-Lead TO-220-5 (T) MIC39150/39151 10 May 2000 MIC39150/39151 Micrel 0.176 ±0.005 0.405±0.005 0.065 ±0.010 20°±2° 0.050 ±0.005 0.050±0.005 0.360±0.005 0.600±0.025 SEATING PLANE 0.004 +0.004 –0.008 0.100 BSC 8° MAX 0.050 0.100 ±0.01 0.015 ±0.002 DIM. = INCH 3-Lead TO-263 (U) 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 0.067±0.005 0.032 ±0.003 8° MAX 0.100 ±0.01 0.015 ±0.002 DIM. = INCH 5-Lead TO-263-5 (U) May 2000 11 MIC39150/39151 MIC39150/39151 Micrel MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB USA http://www.micrel.com This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc. © 2000 Micrel Incorporated MIC39150/39151 12 May 2000