MIC5239 Micrel MIC5239 Low Quiescent Current 500mA µCap LDO Regulator Advance Information General Description Features The MIC5239 is a low quiescent current, µCap low-dropout regulator. With a maximum operating input voltage of 30V and a quiescent current of 23µA, it is ideal for supplying keepalive power in systems with high-voltage batteries. Capable of 500mA output, the MIC5239 has a dropout voltage of only 350mV. It can provide high output current for applications such as USB. As a µCap LDO, the MIC5239 is stable with either a ceramic or a tantalum output capacitor. It only requires a 3.3µF output capacitor for stability. The MIC5239 includes a logic compatible enable input and an undervoltage error flag indicator. Other features of the MIC5239 include thermal shutdown, current-limit, overvoltage shutdown, load-dump protection, reverse leakage protections, and reverse battery protection. Available in the thermally enhanced SOIC-8, MSOP-8 and SOT-223, the MIC5239 comes in fixed 3.0V and adjustable voltages. For other output voltages, contact Micrel. • • • • • • • • • • • • • Ultra-low quiescent current (IQ = 23µA @IO = 100µA) Continuious 500mA output current Wide input range: 2.3V to 30V Low dropout voltage: 350mV @500mA; ±1.0% initial output accuracy Stable with ceramic or tantalum output capacitor Logic compatible enable input Low output voltage error flag indicator Overcurrent protection Thermal shutdown Reverse-leakage protection Reverse-battery protection High-power SOIC-8, MSOP-8 and SOT-223 packages Applications • USB power supply • Keep-alive supply in notebook and portable personal computers • Logic supply from high-voltage batteries • Automotive electronics • Battery-powered systems Typical Application MIC5239 IN OUT VIN 30V EN FLG GROUND CURRENT (µA) 40 VOUT 3.0V/100µA IGND = 23µA GND Regulator with Low IO and Low IQ 35 IOUT = 1mA IOUT = 100µA 30 25 20 15 10 4 IOUT = 10µA 9 14 19 24 INPUT VOLTAGE (V) 29 Ground Current vs. Input Voltage Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com January 2002 1 MIC5239 MIC5239 Micrel Ordering Information Part Number * Voltage Junction Temp. Range Package MIC5239-3.0BMM 3.0V –40°C to +125°C 8-lead MSOP MIC5239-3.0BS 3.0V –40°C to +125°C SOT-223 MIC5239-3.0BM 3.0V –40°C to +125°C 8-lead SOIC MIC5239BMM ADJ –40°C to +125°C 8-lead MSOP MIC5239BM ADJ –40°C to +125°C 8-lead SOIC Pin Configuration EN 1 8 GND EN 1 8 GND FLG 2 7 GND ADJ 2 7 GND IN 3 6 GND IN 3 6 GND OUT 4 5 GND OUT 4 5 GND SOIC-8 (M) MSOP-8 (MM) (Fixed) SOIC-8 (M) MSOP-8 (MM) (Adj.) GND TAB 1 IN 2 3 GND OUT SOT-223 (S) Pin Description Pin Number Pin Number MSOP-8/SOIC-8 SOT-223 Pin Name Pin Function 2 (Fixed) - FLG Error FLAG (Output): Open-collector output is active low when the output is out of regulation due to insufficient input voltage or excessive load. An external pull-up resistor is required. 2 (Adj) - ADJ Adjustable Feedback Input. Connect to voltage divider network. 3 1 IN 4 3 OUT 1 - EN 5–8 2 GND MIC5239 Power supply input. Regulated Output Enable (Input): Logic low = shutdown; logic high = enabled. Ground: Pins 5, 6, 7, and 8 are internally connected in common via the leadframe. 2 January 2002 MIC5239 Micrel Absolute Maximum Ratings (Note 1) Operating Ratings (Note 2) Supply Voltage (VIN) ..................................... –20V to +32V Enable Input Voltage (VEN) .......................... –0.3V to +32V Power Dissipation (PD), Note 3 ............... Internally Limited Junction Temperature (TJ) ....................... –40°C to +125°C Storage Temperature (TS) ....................... –65°C to +150°C Lead Temperature (soldering, 5 sec.) ....................... 260°C ESD Rating, Note 4 Supply Voltage (VIN) ........................................ 2.3V to 30V Enable Input Voltage (VEN) ................................. 0V to 30V Junction Temperature (TJ) ....................... –40°C to +125°C Package Thermal Resistance MSOP (θJA) ......................................................... 80°C/W SOT-223 (θJA) ..................................................... 50°C/W Electrical Characteristics VIN = VOUT + 1V; VEN ≥ 2.0V; IOUT = 100µA; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted. Symbol Parameter Conditions VOUT Output Voltage Accuracy variation from nominal VOUT ∆VOUT/VOUT Line Regulation VIN = VOUT + 1V to 30V ∆VOUT/VOUT Load Regulation ∆V Dropout Voltage, Note 6 IGND Ground Pin Current Min Typ Max Units 1 +2 % % 0.06 0.5 % IOUT = 100µA to 500mA, Note 5 0.5 1 % IOUT = 100µA 50 IOUT = 150mA 260 IOUT = 500mA 350 VEN ≥ 2.0V, IOUT = 100µA 23 40 45 µA µA VEN ≥ 2.0V, IOUT = 150mA 1.3 5 mA VEN ≥ 2.0V, IOUT = 500mA 8.5 15 mA –1 –2 mV 350 400 mV mV mV IGND(SHDN) Ground Pin in Shutdown VEN ≤ 0.6V, VIN = 30V 0.1 1 µA ISC Short Circuit Current VOUT = 0V 850 1200 mA en Output Noise 10Hz to 100kHz, VOUT = 3.0V, CL = 3.3µF 160 µVrms Low Threshold % of VOUT 94 % High Threshold % of VOUT 95 % VOL FLAG Output Low Voltage VIN = VOUT(nom) – 0.12VOUT, IOL = 200µA 150 mV ILEAK FLAG Output Leakage VOH = 30V 0.1 µA VIL Input Low Voltage regulator off VIH Input High Voltage regulator on 2.0 IIN Enable Input Current VEN = 0.6V, regulator off –1.0 –2.0 FLAG Output VFLG Enable Input 0.6 V V 0.01 1.0 2.0 µA µA VEN = 2.0V, regulator on 0.15 1.0 2.0 µA µA VEN = 30V, regulator on 0.5 2.5 5.0 µA µA Note 1. Exceeding the absolute maximum rating may damage the device. Note 2. The device is not guaranteed to function outside its operating rating. Note 3: The maximum allowable power dissipation of any TA (ambient temperature) is PD(max) = (TJ(max) – TA) ÷ θJA. Exceeding the maximum allowable power dissipation will result in excessive die termperature, and the regulator will go into thermal shutdown. The θJA of the MIC5239x.xBMM (all versions) is 80°C/W, the MIC5239-x.xBM (all versions) is 63°C/W, and the MIC5239-x.xBS (all versions) is 50°C/W mounted on a PC board (see “Thermal Characteristics” for further details). January 2002 3 MIC5239 MIC5239 Micrel Note 4. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF. Note 5: Regulation is measured at constant junction temperature using pulse testing with a low duty-cycle. Changes in output voltage due to heating effects are covered by the specification for thermal regulation. Note 6: Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1.0V differential. MIC5239 4 January 2002 MIC5239 Micrel Typical Characteristics (VO = 3V) Power Supply Rejection Ratio 450 DROPOUT VOLTAGE (mV) ILOAD = 500mA 40 30 20 10 0 0.01 0.1 1 10 100 FREQUENCY (Hz) 350 300 250 200 150 100 50 0 0 1000 1.5 ILOAD = 500mA 1 0.5 6000 5000 4000 3000 2000 1000 0 0 Ground Pin Current vs. Temperature 3 GROUND CURRENT (mA) 80 75 70 65 60 55 ILOAD = 10mA 50 -40 -20 0 VIN = 4V GROUND CURRENT (µA) 2 GROUND CURRENT (µA) 100 Ground Pin Current vs. Output Current 7000 0 0 0.5 1 1.5 2 2.5 3 3.5 4 INPUT VOLTAGE (V) 20 40 60 80 100 120 100 200 300 400 500 OUTPUT CURRENT (mA) Ground Pin Current vs. Temperature 2.9 2.8 2.5 2.4 2.3 2.2 2.1 2 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) GROUND CURRENT (mA) 80 70 20 10 0 1.5 January 2002 IOUT = 100µA IOUT = 10µA 2 2.5 3 3.5 INPUT VOLTAGE (V) 22 20 18 16 14 12 10 0 4 IOUT=500mA 6.4 IOUT = 250mA 2.4 0.4 1.5 100 200 300 400 500 OUTPUT CURRENT (µA) Ground Pin Current vs. Temperature ILOAD = 500mA 9.5 9 8.5 8 7.5 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 40 8.4 4.4 VIN = 4V VIN = 12V Ground Pin Current vs. Input Voltage 12.4 10.4 VIN = 30V VIN = 24V 10 14.4 IOUT = 10mA 40 30 26 24 Ground Pin Current vs. Input Voltage Ground Pin Current vs. Input Voltage 60 50 IOUT = 1mA 30 28 10.5 ILOAD = 250mA 2.7 2.6 TEMPERATURE (°C) GROUND CURRENT (µA) 200 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) GROUND CURRENT (mA) 2.5 I LOAD = 250mA GROUND CURRENT (µA) OUTPUT VOLTAGE (V) ILOAD = 100µA IOUT = 500mA 300 100 200 300 400 500 OUTPUT CURRENT (mA) 8000 Dropout Voltage vs. Temperature 400 9000 3.5 100 90 500 Ground Pin Current vs. Output Current Dropout Characteristics 3 600 400 GROUND CURRENT (µA) PSRR (dB) 50 Dropout Voltage vs. Output Current DROPOUT VOLTAGE (mV) 60 2 2.5 3 3.5 INPUT VOLTAGE (V) 5 4 35 IOUT = 1mA IOUT = 100µA 30 25 20 15 10 4 IOUT = 10µA 9 14 19 24 INPUT VOLTAGE (V) 29 MIC5239 MIC5239 Micrel 3.05 100 3.04 3.03 80 60 40 20 0 -20 VEN = 5V RLOAD = 30Ω -10 0 SUPPLY VOLTAGE (V) Output Voltage vs. Temperature ILOAD = 100µA 3.02 3.01 3 2.99 2.98 2.97 2.96 2.95 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 10 SHORT CIRCUIT CURRENT (mA) 120 OUTPUT VOLTAGE (V) INPUT CURRENT (mA) Input Current 900 Short Circuit Current 800 700 600 500 400 300 200 100 VIN = 4V 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) OUTPUT CURRENT OUTPUT VOLTAGE (500mA/div.) (500mV/div.) Load Transient Response 500mA 0mA VIN = 4V VOUT = 3V COUT = 4.7µF ceramic TIME (400µs/div.) MIC5239 6 January 2002 MIC5239 Micrel Functional Diagram IN OUT EN ENABLE FLAG VREF GND Block Diagram - Fixed Voltages OUT IN EN R1 ENABLE ADJ R2 GND Block Diagram - Adjustable Voltages January 2002 7 MIC5239 MIC5239 Micrel Error Detection Comparator Output The FLAG pin is an open collector output which goes low when the output voltage drops 5% below it’s internally programmed level. It senses conditions such as excessive load (current limit), low input voltage, and over temperature conditions. Once the part is disabled via the enable input, the error flag output is not valid. Overvoltage conditions are not reflected in the error flag output. The error flag output is also not valid for input voltages less than 2.3V. The error output has a low voltage of 400mV at a current of 200µA. In order to minimize the drain on the source used for the pull-up, a value of 200k to 1MΩ is suggested for the error flag pull-up. This will guarantee a maximum low voltage of 0.4V for a 30V pull-up potential. An unused error flag can be left unconnected. Application Information The MIC5239 provides all of the advantages of the MIC2950: wide input voltage range, load dump (positive transients up to 60V), and reversed-battery protection, with the added advantages of reduced quiescent current and smaller package. Additionally, when disabled, quiescent current is reduced to 0.1µA. Enable A low on the enable pin disables the part, forcing the quiescent current to less than 0.1µA. Thermal shutdown and the error flag are not functional while the device is disabled. The maximum enable bias current is 2µA for a 2.0V input. An open collector pull-up resistor tied to the input voltage should be set low enough to maintain 2V on the enable input. Figure 1 shows an open collector output driving the enable pin through a 200k pull-up resistor tied to the input voltage. In order to avoid output oscillations, slow transitions from low to high should be avoided. 200k VIN 5V 4.75V Output Voltage VALID ERROR Error FLAG Output Input Voltage VOUT 200k FLG GND COUT 5V 1.3V 0V Thermal Shutdown The MIC5239 has integrated thermal protection. This feature is only for protection purposes. The device should never be intentionally operated near this temperature as this may have detrimental effects on the life of the device. The thermal shutdown may become inactive while the enable input is transitioning a high to a low. When disabling the device via the enable pin, transition from a high to low quickly. This will insure that the output remains disabled in the event of a thermal shutdown. Current Limit Figure 4 displays a method for reducing the steady state short circuit current. The duration that the supply delivers current is set by the time required for the error flag output to discharge the 4.7µF capacitor tied to the enable pin. The off time is set by the 200K resistor as it recharges the 4.7µF capacitor, enabling the regulator. This circuit reduces the short circuit current from 800mA to 40mA while allowing for regulator restart once the short is removed. Figure 1. Remote Enable Input Capacitor An input capacitor may be required when the device is not near the source power supply or when supplied by a battery. Small, surface mount, ceramic capacitors can be used for bypassing. Larger values may be required if the source supply has high ripple. Output Capacitor The MIC5239 has been designed to minimize the effect of the output capacitor ESR on the closed loop stability. As a result, ceramic or film capacitors can be used at the output. Figure 2 displays a range of ESR values for a 10µF capacitor. Virtually any 10µF capacitor with an ESR less than 3.4Ω is sufficient for stability over the entire input voltage range. Stability can also be maintained throughout the specified load and line conditions with 4.7µF film or ceramic capacitors. OUTPUT CAPACITOR ESR (Ω) NOT VALID Figure 3. Error FLAG Output Timing SHUTDOWN ENABLE 5 1N4148 4 200k 3 MIC5239 IN OUT VIN 5V Stable Region 2 1 0 TJ = 25°C VOUT = 10µF 5 10 15 SHUTDOWN ENABLE 20 25 VERR VOUT 200k EN FLG GND COUT 4.7µF 30 Figure 4. Remote Enable with Short-Circuit Current Foldback INPUT VOLTAGE (V) Figure 2. Output Capacitor ESR MIC5239 NOT VALID VERR MIC5239 IN OUT EN 0V 8 January 2002 MIC5239 Micrel Thermal Characteristics The MIC5239 is a high input voltage device, intended to provide 500mA of continuous output current in two very small profile packages. The power MSOP-8 allow the device to dissipate about 50% more power than their standard equivalents. Power MSOP-8 Thermal Characteristics 400 300 200 0.25 0.50 0.75 1.00 1.25 1.50 POWER DISSIPATION (W) Figure 6. Copper Area vs. Power-MSOP Power Dissipation (∆ (∆TJA) Figure 6 shows copper area versus power dissipation with each trace corresponding to a different temperature rise above ambient. From these curves, the minimum area of copper necessary for the part to operate safely can be determined. The maximum allowable temperature rise must be calculated to determine operation along which curve. ∆T = TJ(max) – TA(max) TJ(max) = 125°C TA(max) = maximum ambient operating temperature For example, the maximum ambient temperature is 50°C, the ∆T is determined as follows: ∆T = 125°C – 50°C ∆T = 75°C Using Figure 6, the minimum amount of required copper can be determined based on the required power dissipation. Power dissipation in a linear regulator is calculated as follows: PD = (VIN – VOUT) IOUT + VIN · IGND If we use a 3V output device and a 28V input at moderate output current of 25mA, then our power dissipation is as follows: PD = (28V – 3V) × 25mA + 28V × 250µA PD = 625mW + 7mW PD = 632mW From Figure 6, the minimum amount of copper required to operate this application at a ∆T of 75°C is 110mm2. Quick Method Determine the power dissipation requirements for the design along with the maximum ambient temperature at which the device will be operated. Refer to Figure 7, which shows safe operating curves for three different ambient temperatures: 25°C, 50°C and 85°C. From these curves, the minimum amount of copper can be determined by knowing the maximum power dissipation required. If the maximum ambient temperature is 50°C and the power dissipation is as above, 639mW, the curve in Figure 7 shows that the required area of copper is 110mm2. The θJA of this package is ideally 80°C/W, but it will vary depending upon the availability of copper ground plane to which it is attached. θJA ground plane heat sink area AMBIENT printed circuit board Figure 5. Thermal Resistance Using the power MSOP-8 reduces the θJC dramatically and allows the user to reduce θCA. The total thermal resistance, θJA (junction-to-ambient thermal resistance) is the limitingfactor in calculating the maximum power dissipation capability of the device. Typically, the power MSOP-8 has a θJC of 80°C/W, this is significantly lower than the standard MSOP-8 which is typically 200°C/W. θCA is reduced because pins 5 through 8 can now be soldered directly to a ground plane which significantly reduces the case-to-sink thermal resistance and sink to ambient thermal resistance. Low-dropout linear regulators from Micrel are rated to a maximum junction temperature of 125°C. It is important not to exceed this maximum junction temperature during operation of the device. To prevent this maximum junction temperature from being exceeded, the appropriate ground plane heat sink must be used. January 2002 500 0 0 MSOP-8 θCA 600 100 One of the secrets of the MIC5239’s performance is its power MSOP-8 package featuring half the thermal resistance of a standard MSOP-8 package. Lower thermal resistance means more output current or higher input voltage for a given package size. Lower thermal resistance is achieved by joining the four ground leads with the die attach paddle to create a singlepiece electrical and thermal conductor. This concept has been used by MOSFET manufacturers for years, proving very reliable and cost effective for the user. Thermal resistance consists of two main elements, θJC (junction-to-case thermal resistance) and θCA (case-to-ambient thermal resistance). See Figure 5. θJC is the resistance from the die to the leads of the package. θCA is the resistance from the leads to the ambient air and it includes θCS (case-tosink thermal resistance) and θSA (sink-to-ambient thermal resistance). θJC 700 100°C COPPER AREA (mm2) 800 40°C 50°C 55°C 65°C 75°C 85°C 900 9 MIC5239 MIC5239 Micrel Power SOIC-8 Thermal Characteristics 900 COPPER AREA (mm2) 800 700 T = 125°C J 85°C The power-SOIC-8 package follows the same idea as the power-MSOP-8 package, using four ground leads with the die attach paddle to create a single-piece electrical and thermal conductor, reducing thermal resistance and increasing power dissipation capability. Quick Method Determine the power dissipation requirements for the design along with the maximum ambient temperature at which the device will be operated. Refer to Figure 9, which shows safe operating curves for three different ambient temperatures, 25°C, 50°C, and 85°C. From these curves, the minimum amount of copper can be determined by knowing the maximum power dissipation required. If the maximum ambient temperature is 50°C, and the power dissipation is 632mW, the curve in Figure 9 shows that the required area of copper is less than 100mm2,when using the power SOIC-8. Adjustable Regulator Application 50°C 25°C 600 500 400 300 200 100 0 0 0.25 0.50 0.75 1.00 1.25 1.50 POWER DISSIPATION (W) Figure 7. Copper Area vs. Power-MSOP Power Dissipation (TA) 700 ∆TJA = 100°C COPPER AREA (mm2) 800 40°C 50°C 55°C 65°C 75°C 85°C 900 600 500 400 300 200 MIC5239BM/MM 100 0 0 VIN 0.25 0.50 0.75 1.00 1.25 1.50 POWER DISSIPATION (W) 2 4 3 IN EN ADJ GND Figure 8. Copper Area vs. Power-SOIC ∆TJA) Power Dissipation (∆ VOUT OUT 1 R1 1µF R2 5-8 COPPER AREA (mm2) 900 800 TJ = 125°C 700 85°C Figure 10. Adjustable Voltage Application 50°C 25°C The MIC5239BM can be adjusted from 1.24V to 20V by using two external resistors (Figure 10). The resistors set the output voltage based on the following equation: 600 500 400 300 R1 ) R2 Where VREF = 1.23V. Feeback resistor R2 should be no larger than 300kΩ. VOUT = VREF (1 + 200 100 0 0 0.25 0.50 0.75 1.00 1.25 1.50 POWER DISSIPATION (W) Figure 9. Copper Area vs. Power-SOIC Power Dissipation (TA) The same method of determining the heat sink area used for the power-MSOP-8 can be applied directly to the powerSOIC-8. The same two curves showing power dissipation versus copper area are reproduced for the power-SOIC-8 and they can be applied identically. MIC5239 10 January 2002 MIC5239 Micrel Package Information 3.15 (0.124) 2.90 (0.114) CL 3.71 (0.146) 7.49 (0.295) 3.30 (0.130) 6.71 (0.264) CL 2.41 (0.095) 2.21 (0.087) 1.04 (0.041) 0.85 (0.033) 4.7 (0.185) 4.5 (0.177) 0.10 (0.004) 0.02 (0.0008) DIMENSIONS: MM (INCH) 6.70 (0.264) 6.30 (0.248) 1.70 (0.067) 16° 1.52 (0.060) 10° 10° MAX 0.38 (0.015) 0.25 (0.010) 0.84 (0.033) 0.64 (0.025) 0.91 (0.036) MIN SOT-223 (S) 0.122 (3.10) 0.112 (2.84) 0.199 (5.05) 0.187 (4.74) DIMENSIONS: INCH (MM) 0.120 (3.05) 0.116 (2.95) 0.036 (0.90) 0.032 (0.81) 0.043 (1.09) 0.038 (0.97) 0.012 (0.30) R 0.012 (0.03) 0.0256 (0.65) TYP 0.008 (0.20) 0.004 (0.10) 5° MAX 0° MIN 0.007 (0.18) 0.005 (0.13) 0.012 (0.03) R 0.039 (0.99) 0.035 (0.89) 0.021 (0.53) 8-Lead MSOP (MM) January 2002 11 MIC5239 MIC5239 Micrel 0.026 (0.65) MAX) PIN 1 0.157 (3.99) 0.150 (3.81) DIMENSIONS: INCHES (MM) 0.020 (0.51) 0.013 (0.33) 0.050 (1.27) TYP 0.064 (1.63) 0.045 (1.14) 45° 0.0098 (0.249) 0.0040 (0.102) 0.197 (5.0) 0.189 (4.8) 0°–8° SEATING PLANE 0.010 (0.25) 0.007 (0.18) 0.050 (1.27) 0.016 (0.40) 0.244 (6.20) 0.228 (5.79) 8-Lead SOIC (M) MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 TEL USA + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB 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. © 2002 Micrel Incorporated MIC5239 12 January 2002