MIC39100/39101/39102 Micrel MIC39100/39101/39102 1A Low-Voltage Low-Dropout Regulator General Description Features The MIC39100, MIC39101, and MIC39102 are 1A low-dropout linear voltage regulators that provide low-voltage, high-current output from an extremely small package. Utilizing Micrel’s proprietary Super βeta PNP™ pass element, the MIC39100/1/2 offers extremely low dropout (typically 410mV at 1A) and low ground current (typically 11mA at 1A). The MIC39100 is a fixed output regulator offered in the SOT-223 package. The MIC39101 and MIC39102 are fixed and adjustable regulators, respectively, in a thermally enhanced power 8-lead SOIC package. The MIC39100/1/2 is ideal for PC add-in cards that need to convert from standard 5V to 3.3V, 3.3V to 2.5V or 2.5V to 1.8V. A guaranteed maximum dropout voltage of 630mV over all operating conditions allows the MIC39100/1/2 to provide 2.5V from a supply as low as 3.13V and 1.8V from a supply as low as 2.43V. The MIC39100/1/2 is fully protected with overcurrent limiting, thermal shutdown, and reversed-battery protection. Fixed voltages of 5.0V, 3.3V, 2.5V, and 1.8V are available on MIC39100/1 with adjustable output voltages to 1.24V on MIC39102. For other voltages, contact Micrel. • Fixed and adjustable output voltages to 1.24V • 410mV typical dropout at 1A Ideal for 3.0V to 2.5V conversion Ideal for 2.5V to 1.8V conversion • 1A minimum guaranteed output current • 1% initial accuracy • Low ground current • Current limiting and thermal shutdown • Reversed-battery protection • Reversed-leakage protection • Fast transient response • Low-profile SOT-223 package • Power SO-8 package Applications • • • • • • • LDO linear regulator for PC add-in cards PowerPC™ power supplies High-efficiency linear power supplies SMPS post regulator Multimedia and PC processor supplies Battery chargers Low-voltage microcontrollers and digital logic Typical Applications 100k VIN 3.3V MIC39100 IN OUT GND VIN 3.3V 2.5V 10µF tantalum ENABLE SHUTDOWN 2.5V/1A Regulator Error Flag Output MIC39101 IN OUT EN FLG R1 2.5V 10µF tantalum GND 2.5V/1A Regulator with Error Flag VIN 2.5V ENABLE SHUTDOWN MIC39102 IN EN OUT ADJ GND 1.5V R1 R2 10µF tantalum 1.5V/1A Adjustable Regulator Super βeta PNP is a 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 August 2005 1 M9999-082505-B MIC39100/39101/39102 Micrel Ordering Information Part Number Voltage Junction Temp. Range Package Standard RoHS Compliant MIC39100-1.8BS MIC39100-1.8WS* 1.8V -40°C to +125°C SOT-223 MIC39100-2.5BS MIC39100-2.5WS* 2.5V -40°C to +125°C SOT-223 MIC39100-3.3BS MIC39100-3.3WS* 3.3V -40°C to +125°C SOT-223 MIC39100-5.0BS MIC39100-5.0WS* 5.0V -40°C to +125°C SOT-223 MIC39101-1.8BM MIC39101-1.8YM 1.8V -40°C to +125°C SOIC-8 MIC39101-2.5BM MIC39101-2.5YM 2.5V -40°C to +125°C SOIC-8 MIC39101-3.3BM MIC39101-3.3YM 3.3V -40°C to +125°C SOIC-8 MIC39101-5.0BM MIC39101-5.0YM 5.0V -40°C to +125°C SOIC-8 MIC39102BM MIC39102YM Adj. -40°C to +125°C SOIC-8 * RoHS compliant with ‘high-melting solder’ exemption. Pin Configuration GND TAB 1 IN 2 3 GND OUT MIC39100-x.x Fixed SOT-223 (S) EN 1 8 GND EN 1 8 GND IN 2 7 GND IN 2 7 GND OUT 3 6 GND OUT 3 6 GND FLG 5 GND ADJ 4 5 GND 4 MIC39101-x.x Fixed SOIC-8 (M) MIC39102 Adjustable SOIC-8 (M) Pin Description Pin No. Pin No. Pin No. MIC39100 MIC39101 MIC39102 1 3 1 1 2 3 M9999-082505 5–8 Pin Function EN Enable (Input): CMOS-compatible control input. Logic high = enable, logic low or open = shutdown. 2 IN Supply (Input) 3 OUT Regulator Output FLG Flag (Output): Open-collector error flag output. Active low = output undervoltage. 4 ADJ Adjustment Input: Feedback input. Connect to resitive voltage-divider network. 5–8 GND Ground 4 2, TAB Pin Name 2 August 2005 MIC39100/39101/39102 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 SOT-223 (θJC) ..................................................... 15°C/W SOIC-8 (θJC) ........................................................ 20°C/W Electrical Characteristics(Note 12) VIN = VOUT + 1V; VEN = 2.25V; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted Symbol Parameter Condition VOUT Output Voltage 10mA 10mA ≤ IOUT ≤ 1A, VOUT + 1V ≤ VIN ≤ 8V Line Regulation Load Regulation ΔVOUT/ΔT ppm/°C VDO Output Voltage Temp. Coefficient, Min IOUT = 10mA, VOUT + 1V ≤ VIN ≤ 16V Max Units 1 2 % % 0.06 0.5 % VIN = VOUT + 1V, 10mA ≤ IOUT ≤ 1A, 0.2 1 % 40 100 IOUT = 100mA, ΔVOUT = –1% 140 200 250 IOUT = 500mA, ΔVOUT = –1% 275 Note 5 Dropout Voltage, Note 6 IOUT = 750mA, ΔVOUT = –1% IOUT = 1A, ΔVOUT = –1% IGND Typ –1 –2 Ground Current, Note 7 mV 330 500 mV 410 550 630 mV mV IOUT = 100mA, VIN = VOUT + 1V 400 µA 4 mA IOUT = 750mA, VIN = VOUT + 1V 6.5 mA 11 20 mA VOUT = 0V, VIN = VOUT + 1V 1.8 2.5 A 0.8 V 30 75 µA µA 2 4 µA µA IOUT = 500mA, VIN = VOUT + 1V IOUT = 1A, VIN = VOUT + 1V IOUT(lim) Current Limit VEN Enable Input Voltage logic low (off) IEN Enable Input Current VEN = 2.25V Enable Input mV mV logic high (on) 2.25 1 V 15 VEN = 0.8V Flag Output IFLG(leak) Output Leakage Current VOH = 16V 0.01 1 2 µA µA VFLG(do) Output Low Voltage VIN = 2.250V, IOL, = 250µA, Note 9 210 300 400 mV mV VFLG Low Threshold High Threshold Hysteresis August 2005 % of VOUT 93 % 99.2 % of VOUT 1 3 % % M9999-082505-B MIC39100/39101/39102 Symbol Parameter Micrel Condition Min Typ Max Units 1.228 1.215 1.203 1.240 1.252 1.265 1.277 V V V 40 80 120 nA nA MIC39102 Only Reference Voltage Note 10 Adjust Pin Bias Current Reference Voltage ppm/°C Note 7 20 Temp. Coefficient Adjust Pin Bias Current Temp. Coefficient 0.1 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. nA/°C Output voltage temperature coefficient is ΔVOUT(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. Note 9. VEN ≤ 0.8V, VIN ≤ 8V, and VOUT = 0V. For a 2.5V device, VIN = 2.250V (device is in dropout). Note 10. VREF ≤ VOUT ≤ (VIN – 1V), 2.25V ≤ VIN ≤ 16V, 10mA ≤ IL ≤ 1A, TJ = TMAX. Note 11. Thermal regulation is defined as the change in output voltage at a time t after a change in power dissipation is applied, excluding load or line regulation effects. Specifications are for a 200mA load pulse at VIN = 16V for t = 10ms. Note 12. Specification for packaged product only. M9999-082505 4 August 2005 MIC39100/39101/39102 Micrel Typical Characteristics P ower S upply R ejec tion R atio PSRR (dB) 40 60 40 40 20 I OUT = 1A C OUT = 47µF C IN = 0 0 1E+1 1k 1E+4 10k 1E+5 1M 10 1E+2 100k 1E+6 100 1E+3 FREQUENCY (Hz) 20 I OUT = 1A C OUT = 10µF C IN = 0 0 1E+1 1k 1E+4 10k 1E+5 1M 10 1E+2 100k 1E+6 100 1E+3 FREQUENCY (Hz) P ower S upply R ejec tion R atio Dropout V oltage vs . Output C urrent Dropout V oltage vs . T emperature I OUT = 1A C OUT = 47µF C IN = 0 0 1E+1 1k 1E+4 10k 1E+5 1M 10 1E+2 100k 1E+6 100 1E+3 FREQUENCY (Hz) Dropout C harac teris tic s (2.5V ) 2.8 2.6 OUTPUT VOLTAGE (V) 2.2 I LOAD =750mA I LOAD =1A 1.6 2 3.5 G round C urrent vs . S upply V oltage (2.5V ) 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 2.3 2.6 2.9 3.2 SUPPLY VOLTAGE (V) August 2005 450 350 300 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 14 3.0 I LOAD =750mA I LOAD =1A 3.2 3.6 4.0 SUPPLY VOLTAGE (V) 8 10 8 G round C urrent vs . S upply V oltage (2.5V ) 1.8V 2.5V 3.3V 6 4 2 0 0 4.4 200 400 600 800 OUTPUT CURRENT (mA) 1000 G round C urrent vs . S upply V oltage (3.3V ) 1.4 1.2 25 I LOAD =1A 20 15 10 5 0 G round C urrent vs . Output C urrent 12 3.2 2.6 2.5V 400 I LOAD =100mA 2.8 1.8V 3.3V 30 I LOAD =10mA 2 4 6 SUPPLY VOLTAGE (V) 500 Dropout C harac teris tic s (3.3V ) 35 I LOAD =100mA 0 250 500 750 1000 1250 OUTPUT CURRENT (mA) 2.4 2.8 GROUND CURRENT (mA) 1.4 T A = 25°C 3.4 2.4 1.8 1.8V 3.6 I LOAD =100mA 2.0 3.3V 0 I LOAD = 1A 550 2.5V GROUND CURRENT (mA) 20 600 DROPOUT VOLTAGE (mV) 40 500 450 400 350 300 250 200 150 100 50 0 GROUND CURRENT (mA) V IN = 3.3V V OUT = 2.5V 60 OUTPUT VOLTAGE (V) V IN = 3.3V V OUT = 2.5V 20 I OUT = 1A C OUT = 10µF C IN = 0 0 1E+1 1k 1E+4 10k 1E+5 1M 10 1E+2 100k 1E+6 100 1E+3 FREQUENCY (Hz) 80 GROUND CURRENT (mA) P ower S upply R ejec tion R atio 80 V IN = 5V V OUT = 3.3V 60 DROPOUT VOLTAGE (mV) PSRR (dB) 60 PSRR (dB) 80 V IN = 5V V OUT = 3.3V PSRR (dB) 80 P ower S upply R ejec tion R atio 0 2 4 6 SUPPLY VOLTAGE (V) 5 8 1.0 I LOAD =100mA 0.8 0.6 I LOAD =10mA 0.4 0.2 0 0 2 4 6 SUPPLY VOLTAGE (V) 8 M9999-082505-B MIC39100/39101/39102 1.0 I LOAD =1A 30 20 10 0 0 2 4 6 SUPPLY VOLTAGE (V) I LOAD =10mA 0.6 3.3V 0.4 0.2 2.5V 1.8V 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 8 G round C urrent vs . T emperature 20 0.8 GROUND CURRENT (mA) 40 G round C urrent vs . T emperature GROUND CURRENT (mA) G round C urrent vs . S upply V oltage (3.3V ) 50 GROUND CURRENT (mA) Micrel 3.40 Output V oltage vs . T emperature 5.0 4.5 4.0 3.5 3.0 2.5 2.0 2.5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 3.20 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 12 V IN = 5V 5 FLAG VOLTAGE (V) 3.25 E rror F lag P ull-Up R es is tor 6 F LAG HIG H (OK ) 4 3 2 F LAG LOW (F AULT ) 1 0 0.01 3.30 0.1 M9999-082505 1 10 100 1000 10000 RESISTANCE (kΩ) 10 SHORT CIRCUIT CURRENT (A) 5 T ypical 3.3V Device E nable C urrent vs . T emperature 8 6 4 2 0 -40 -20 0 20 40 60 80 100 120 140 TEMPERATURE (°C) 6 2.0 3.3V 1.8V S hort C irc uit vs . T emperature 3.3V 1.5 2.5V 1.0 1.8V 0.5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) 250 V IN = V OUT + 1V V E N = 2.4V 200 FLAG VOLTAGE (mV) 3.3V OUTPUT VOLTAGE (V) 10 3.35 ENABLE CURRENT (µA) GROUND CURRENT (mA) 1.8V 2.5V 2.5V 1.5 1.0 I LOAD = 500mA 0.5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) I LOAD = 1A 15 G round C urrent vs . T emperature F lag-L ow V oltage vs . T emperature F LAG -LOW V OLT AG E 150 100 V IN = 2.25V R P ULL-UP = 22kΩ 50 0 -40 -20 0 20 40 60 80 100 120 140 TEMPERATURE (°C) August 2005 MIC39100/39101/39102 Micrel Functional Characteristics August 2005 7 M9999-082505-B MIC39100/39101/39102 Micrel Functional Diagrams OU T IN OV I LIMIT 1.240V Ref. 18V Thermal Shutdown MIC39100 GND MIC39100 Fixed Regulator Block Diagram OU T IN O.V. ILIMIT 1.180V FL AG Ref. 18V 1.240V EN Thermal Shutdown GND MIC39101 MIC39101 Fixed Regulator with Flag and Enable Block Diagram OU T IN O.V. ILIMIT Ref. 18V 1.240V ADJ EN Thermal Shutdown GND MIC39102 MIC39102 Adjustable Regulator Block Diagram M9999-082505 8 August 2005 MIC39100/39101/39102 Micrel Applications Information 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, surface mount, ceramic chip capacitors can be used for bypassing. Larger values will help to improve ripple rejection by bypassing the input to the regulator, further improving the integrity of the output voltage. Error Flag The MIC39101 features an error flag (FLG), which monitors the output voltage and signals an error condition when this voltage drops 5% below its expected value. The error flag is an open-collector output that pulls low under fault conditions and may sink up to 10mA. Low output voltage signifies a number of possible problems, including an overcurrent fault (the device is in current limit) or low input voltage. The flag output is inoperative during overtemperature conditions. A pull-up resistor from FLG to either VIN or VOUT is required for proper operation. For information regarding the minimum and maximum values of pull-up resistance, refer to the graph in the typical characteristics section of the data sheet. Enable Input The MIC39101 and MIC39102 versions feature an active-high enable input (EN) that allows on-off control of the regulator. Current drain reduces to “zero” when the device is shutdown, with only microamperes of leakage current. The EN input has TTL/CMOS compatible thresholds for simple logic interfacing. EN may be directly tied to VIN and pulled up to the maximum supply voltage Transient Response and 3.3V to 2.5V or 2.5V to 1.8V Conversion The MIC39100/1/2 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 or 1.8V without operating in dropout, NPN-based regulators require an input voltage of 3.7V at the very least. The MIC39100 regulator will provide excellent performance with an input as low as 3.0V or 2.5V respectively. This gives the PNP based regulators a distinct advantage over older, NPN based linear regulators. Minimum Load Current The MIC39100/1/2 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. The MIC39100/1/2 is a high-performance low-dropout voltage regulator suitable for moderate to high-current voltage regulator applications. Its 630mV 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, 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% of the load current. The MIC39100/1/2 regulator is fully protected from damage due to fault conditions. Linear current limiting is provided. 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. V IN C IN MIC39100-x.x IN OUT GND V OUT C OUT Figure 1. Capacitor Requirements Output Capacitor The MIC39100/1/2 requires an output capacitor to maintain stability and improve transient response. Proper capacitor selection is important to ensure proper operation. The MIC39100/1/2 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. Ultra-low-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. August 2005 9 M9999-082505-B MIC39100/39101/39102 Micrel Adjustable Regulator Design VIN MIC39102 IN OUT Using the power SOIC-8 reduces the θJC dramatically and allows the user to reduce θCA. The total thermal resistance, θJA (junction-to-ambient thermal resistance) is the limiting factor in calculating the maximum power dissipation capability of the device. Typically, the power SOIC-8 has a θJC of 20°C/W, this is significantly lower than the standard SOIC-8 which is typically 75°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. VOUT R1 EN ENABLE SHUTDOWN ADJ GND COUT R2 R1 V OUT = 1.240V 1 + R2 Figure 2. Adjustable Regulator with Resistors The MIC39102 allows programming the output voltage anywhere between 1.24V and the 16V 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 SOIC-8 Where VO 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). Power SOIC-8 Thermal Characteristics One of the secrets of the MIC39101/2’s performance is its power SO-8 package featuring half the thermal resistance of a standard SO-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 3. 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 (caseto-sink thermal resistance) and θSA (sink-to-ambient thermal resistance). JA JC AMBIENT printed circuit board Figure 3. Thermal Resistance Figure 4 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. 800 T = 125°C J 700 T A = 85°C COPPER AREA (mm2) °C COPPER AREA (mm2) 700 4 5 5 6 7 8 ∆T J A = 1 900 800 °C °C °C °C °C °C 900 600 500 400 300 200 100 0 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 4. Copper Area vs. Power-SOIC Power Dissipation M9999-082505 ground plane heat sink area CA 0 0.25 0.50 0.75 1.00 1.25 1.50 POWER DISSIPATION (W) Figure 5. Copper Area vs. Power-SOIC Power Dissipation 10 August 2005 MIC39100/39101/39102 Micrel ΔT = TJ(max) – TA(max) TJ(max) = 125°C TA(max) = maximum ambient operating temperature For example, the maximum ambient temperature is 50°C, the ΔT is determined as follows: ΔT = 125°C – 50°C ΔT = 75°C Using Figure 4, 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 2.5V output device and a 3.3V input at an output current of 1A, then our power dissipation is as follows: PD = (3.3V – 2.5V) × 1A + 3.3V × 11mA PD = 800mW + 36mW PD = 836mW From Figure 4, the minimum amount of copper required to operate this application at a ΔT of 75°C is 160mm2. August 2005 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 5, 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, 836mW, the curve in Figure 5 shows that the required area of copper is 160mm2. The θJA of this package is ideally 63°C/W, but it will vary depending upon the availability of copper ground plane to which it is attached. 11 M9999-082505-B MIC39100/39101/39102 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) 8-Lead SOIC (M) MICREL INC. TEL 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA + 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. © 2005 Micrel Incorporated M9999-082505 12 August 2005