MCP1702 250 mA Low Quiescent Current LDO Regulator Features Description • • • • • The MCP1702 is a family of CMOS low dropout (LDO) voltage regulators that can deliver up to 250 mA of current while consuming only 2.0 µA of quiescent current (typical). The input operating range is specified from 2.7V to 13.2V, making it an ideal choice for two to six primary cell battery-powered applications, 9V alkaline and one or two cell Li-Ion-powered applications. • • • • • • 2.0 µA Quiescent Current (typical) Input Operating Voltage Range: 2.7V to 13.2V 250 mA Output Current for Output Voltages ≥ 2.5V 200 mA Output Current for Output Voltages < 2.5V Low Dropout (LDO) voltage - 625 mV typical @ 250 mA (VOUT = 2.8V) 0.4% Typical Output Voltage Tolerance Standard Output Voltage Options: - 1.2V, 1.5V, 1.8V, 2.5V, 2.8V, 3.0V, 3.3V, 4.0V, 5.0V Output voltage range 1.2V to 5.5V in 0.1V Increments (50 mV increments available upon request) Stable with 1.0 µF to 22 µF Output Capacitor Short-Circuit Protection Overtemperature Protection Applications • • • • • • • • • • • • • Battery-powered Devices Battery-powered Alarm Circuits Smoke Detectors CO2 Detectors Pagers and Cellular Phones Smart Battery Packs Low Quiescent Current Voltage Reference PDAs Digital Cameras Microcontroller Power Solar-Powered Instruments Consumer Products Battery Powered Data Loggers Related Literature • AN765, “Using Microchip’s Micropower LDOs”, DS00765, Microchip Technology Inc., 2002 • AN766, “Pin-Compatible CMOS Upgrades to BiPolar LDOs”, DS00766, Microchip Technology Inc., 2002 • AN792, “A Method to Determine How Much Power a SOT-23 Can Dissipate in an Application”, DS00792, Microchip Technology Inc., 2001 © 2007 Microchip Technology Inc. The MCP1702 is capable of delivering 250 mA with only 625 mV (typical) of input to output voltage differential (VOUT = 2.8V). The output voltage tolerance of the MCP1702 is typically ±0.4% at +25°C and ±3% maximum over the operating junction temperature range of -40°C to +125°C. Line regulation is ±0.1% typical at +25°C. Output voltages available for the MCP1702 range from 1.2V to 5.0V. The LDO output is stable when using only 1 µF of output capacitance. Ceramic, tantalum or aluminum electrolytic capacitors can all be used for input and output. Overcurrent limit and overtemperature shutdown provide a robust solution for any application. Package options include the SOT-23A, SOT-89-3, and TO-92. Package Types 3-Pin SOT-23A 3-Pin SOT-89 VIN VIN 3 MCP1702 MCP1702 1 2 1 2 GND VOUT 3 GND VIN VOUT 3-Pin TO-92 123 Bottom View GND VIN VOUT DS22008B-page 1 MCP1702 Functional Block Diagrams MCP1702 VOUT VIN Error Amplifier +VIN Voltage Reference + Overcurrent Overtemperature GND Typical Application Circuits MCP1702 VIN 9V Battery DS22008B-page 2 + CIN 1 µF Ceramic VOUT 3.3V VOUT VIN GND COUT 1 µF Ceramic IOUT 50 mA © 2007 Microchip Technology Inc. MCP1702 1.0 ELECTRICAL CHARACTERISTICS † Notice: Stresses above those listed under “Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operational listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. Absolute Maximum Ratings † VDD...............................................................................+14.5V All inputs and outputs w.r.t. .............(VSS-0.3V) to (VIN+0.3V) Peak Output Current ...................................................500 mA Storage temperature .....................................-65°C to +150°C Maximum Junction Temperature ................................... 150°C Operating Junction Temperature...................-40°C to +125°C ESD protection on all pins (HBM;MM)............... ≥ 4 kV; ≥ 400V DC CHARACTERISTICS Electrical Specifications: Unless otherwise specified, all limits are established for VIN = VOUT(MAX) + VDROPOUT(MAX), Note 1, ILOAD = 100 µA, COUT = 1 µF (X7R), CIN = 1 µF (X7R), TA = +25°C. Boldface type applies for junction temperatures, TJ of -40°C to +125°C. (Note 7) Parameters Sym Min Typ Max Units Conditions Input Operating Voltage VIN Input Quiescent Current Iq 2.7 — 13.2 V Note 1 — 2.0 5 µA IL = 0 mA IOUT_mA 250 — — mA For VR ≥ 2.5V 50 100 — mA For VR < 2.5V, VIN ≥ 2.7V 100 130 — mA For VR < 2.5V, VIN ≥ 2.95V 150 200 — mA For VR < 2.5V, VIN ≥ 3.2V 200 250 — mA For VR < 2.5V, VIN ≥ 3.45V IOUT_SC — 400 — mA VIN = VIN(MIN) (Note 1), VOUT = GND, Current (average current) measured 10 ms after short is applied. VOUT VR-3.0% VR-2.0% VR±0.4 % VR+3.0% VR+2.0% V Note 2 TCVOUT — 50 150 ppm/°C Note 3 Line Regulation ΔVOUT/ (VOUTXΔVIN) -0.3 ±0.1 +0.3 %/V Load Regulation ΔVOUT/VOUT -2.5 ±1.0 +2.5 % Input / Output Characteristics Maximum Output Current Output Short Circuit Current Output Voltage Regulation VOUT Temperature Coefficient Note 1: 2: 3: 4: 5: 6: 7: (VOUT(MAX) + VDROPOUT(MAX)) ≤ VIN ≤ 13.2V, (Note 1) IL = 1.0 mA to 250 mA for VR ≥ 2.5V IL = 1.0 mA to 200 mA for VR < 2.5V, VIN = 3.45V Note 4 The minimum VIN must meet two conditions: VIN ≥ 2.7V and VIN ≥ VOUT(MAX) + VDROPOUT(MAX). VR is the nominal regulator output voltage. For example: VR = 1.2V, 1.5V, 1.8V, 2.5V, 2.8V, 3.0V, 3.3V, 4.0V, or 5.0V. The input voltage VIN = VOUT(MAX) + VDROPOUT(MAX) or VIN = 2.7V (whichever is greater); IOUT = 100 µA. TCVOUT = (VOUT-HIGH - VOUT-LOW) *106 / (VR * ΔTemperature), VOUT-HIGH = highest voltage measured over the temperature range. VOUT-LOW = lowest voltage measured over the temperature range. Load regulation is measured at a constant junction temperature using low duty cycle pulse testing. Changes in output voltage due to heating effects are determined using thermal regulation specification TCVOUT. Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its measured value with an applied input voltage of VOUT(MAX) + VDROPOUT(MAX) or 2.7V, whichever is greater. The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable junction temperature and the thermal resistance from junction to air (i.e., TA, TJ, θJA). Exceeding the maximum allowable power dissipation will cause the device operating junction temperature to exceed the maximum 150°C rating. Sustained junction temperatures above 150°C can impact the device reliability. The junction temperature is approximated by soaking the device under test at an ambient temperature equal to the desired Junction temperature. The test time is small enough such that the rise in the Junction temperature over the ambient temperature is not significant. © 2007 Microchip Technology Inc. DS22008B-page 3 MCP1702 DC CHARACTERISTICS (CONTINUED) Electrical Specifications: Unless otherwise specified, all limits are established for VIN = VOUT(MAX) + VDROPOUT(MAX), Note 1, ILOAD = 100 µA, COUT = 1 µF (X7R), CIN = 1 µF (X7R), TA = +25°C. Boldface type applies for junction temperatures, TJ of -40°C to +125°C. (Note 7) Parameters Dropout Voltage (Note 1, Note 5) Sym VDROPOUT Output Delay Time Output Noise Power Supply Ripple Rejection Ratio Thermal Shutdown Protection Note 1: 2: 3: 4: 5: 6: 7: Min Typ Max Units Conditions — 330 650 mV IL = 250 mA, VR = 5.0V — 525 725 mV IL = 250 mA, 3.3V ≤ VR < 5.0V — 625 975 mV IL = 250 mA, 2.8V ≤ VR < 3.3V — 750 1100 mV IL = 250 mA, 2.5V ≤ VR < 2.8V — — — mV VR < 2.5V, See Maximum Output Current Parameter TDELAY — 1000 — µs VIN = 0V to 6V, VOUT = 90% VR RL = 50Ω resistive eN — 8 PSRR — 44 — dB TSD — 150 — °C µV/(Hz)1/2 IL = 50 mA, f = 1 kHz, COUT = 1 µF f = 100 Hz, COUT = 1 µF, IL = 50 mA, VINAC = 100 mV pk-pk, CIN = 0 µF, VR = 1.2V The minimum VIN must meet two conditions: VIN ≥ 2.7V and VIN ≥ VOUT(MAX) + VDROPOUT(MAX). VR is the nominal regulator output voltage. For example: VR = 1.2V, 1.5V, 1.8V, 2.5V, 2.8V, 3.0V, 3.3V, 4.0V, or 5.0V. The input voltage VIN = VOUT(MAX) + VDROPOUT(MAX) or VIN = 2.7V (whichever is greater); IOUT = 100 µA. TCVOUT = (VOUT-HIGH - VOUT-LOW) *106 / (VR * ΔTemperature), VOUT-HIGH = highest voltage measured over the temperature range. VOUT-LOW = lowest voltage measured over the temperature range. Load regulation is measured at a constant junction temperature using low duty cycle pulse testing. Changes in output voltage due to heating effects are determined using thermal regulation specification TCVOUT. Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its measured value with an applied input voltage of VOUT(MAX) + VDROPOUT(MAX) or 2.7V, whichever is greater. The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable junction temperature and the thermal resistance from junction to air (i.e., TA, TJ, θJA). Exceeding the maximum allowable power dissipation will cause the device operating junction temperature to exceed the maximum 150°C rating. Sustained junction temperatures above 150°C can impact the device reliability. The junction temperature is approximated by soaking the device under test at an ambient temperature equal to the desired Junction temperature. The test time is small enough such that the rise in the Junction temperature over the ambient temperature is not significant. TEMPERATURE SPECIFICATIONS (NOTE 1) Parameters Sym Min Typ Max Units Conditions Temperature Ranges Specified Temperature Range TJ -40 +125 °C Operating Temperature Range TJ -40 +125 °C Storage Temperature Range TA -65 +150 °C θJA — 336 — °C/W θJC — 110 — °C/W θJA — 52 — °C/W θJC — 10 — °C/W θJA — 131.9 — °C/W θJC — 66.3 — °C/W Thermal Package Resistance Thermal Resistance, 3L-SOT-23A Thermal Resistance, 3L-SOT-89 Thermal Resistance, 3L-TO-92 Note 1: EIA/JEDEC JESD51-7 FR-4 0.063 4-Layer Board EIA/JEDEC JESD51-7 FR-4 0.063 4-Layer Board The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable junction temperature and the thermal resistance from junction to air (i.e., TA, TJ, θJA). Exceeding the maximum allowable power dissipation will cause the device operating junction temperature to exceed the maximum 150°C rating. Sustained junction temperatures above 150°C can impact the device reliability. DS22008B-page 4 © 2007 Microchip Technology Inc. MCP1702 2.0 TYPICAL PERFORMANCE CURVES Note: The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power supply range) and therefore outside the warranted range. Note: Unless otherwise indicated: VR = 2.8V, COUT = 1 µF Ceramic (X7R), CIN = 1 µF Ceramic (X7R), IL = 100 µA, TA = +25°C, VIN = VOUT(MAX) + VDROPOUT(MAX). Note: Junction Temperature (TJ) is approximated by soaking the device under test to an ambient temperature equal to the desired junction temperature. The test time is small enough such that the rise in Junction temperature over the Ambient temperature is not significant. 120.00 VOUT = 1.2V 4.00 GND Current (µA) Quiescent Current (µA) 5.00 +130°C 3.00 0°C +90°C +25°C 2.00 1.00 -45°C Temperature = +25°C 100.00 VOUT = 1.2V VIN = 2.7V 80.00 60.00 40.00 20.00 0.00 0.00 2 4 6 8 10 12 14 0 40 80 Input Voltage (V) FIGURE 2-1: Voltage. Quiescent Current vs. Input FIGURE 2-4: Current. +130°C 3.00 +25°C +90°C 2.00 0°C 1.00 -45°C 0.00 200 Temperature = +25°C 100.00 VOUT = 5.0V VIN = 6.0V 80.00 60.00 40.00 VOUT = 2.8V VIN = 3.8V 20.00 0.00 3 5 7 9 11 13 0 50 100 Input Voltage (V) FIGURE 2-2: Voltage. Quiescent Current vs.Input FIGURE 2-5: Current. Quiescent Current (µA) +130°C 3.00 +90°C 2.00 +25°C 200 250 0°C -45°C Ground Current vs. Load 3.00 VOUT = 5.0V 4.00 150 Load Current (mA) 5.00 Quiescent Current (µA) 160 Ground Current vs. Load 120.00 VOUT = 2.8V GND Current (µA) Quiescent Current (µA) 5.00 4.00 120 Load Current (mA) VOUT = 2.8V VIN = 3.8V 2.50 IOUT = 0 mA VOUT = 5.0V VIN = 6.0V 2.00 1.50 VOUT = 1.2V VIN = 2.7V 1.00 0.50 0.00 1.00 6 7 8 9 10 11 12 13 14 Input Voltage (V) FIGURE 2-3: Voltage. Quiescent Current vs.Input © 2007 Microchip Technology Inc. -45 -20 5 30 55 80 105 130 Junction Temperature (°C) FIGURE 2-6: Quiescent Current vs. Junction Temperature. DS22008B-page 5 MCP1702 Note: Unless otherwise indicated: VR = 2.8V, COUT = 1 µF Ceramic (X7R), CIN = 1 µF Ceramic (X7R), IL = 100 µA, TA = +25°C, VIN = VOUT(MAX) + VDROPOUT(MAX). VOUT = 1.2V ILOAD = 0.1 mA 1.23 -45°C 0°C 1.22 1.21 1.20 +130°C +90°C +25°C 1.19 1.23 Output Voltage (V) Output Voltage (V) 1.24 1.18 VOUT = 1.2V 0°C 1.22 -45°C 1.21 +25°C 1.20 +90°C +130°C 1.19 1.18 2 4 6 8 10 12 0 14 20 2.85 +130°C +90°C 2.81 2.80 2.79 0°C -45°C +25°C 2.78 2.77 100 VOUT = 2.8V 2.82 +130°C +90°C 2.81 2.80 2.79 +25°C 2.78 0°C -45°C 2.77 3 4 5 6 7 8 9 10 11 12 13 14 0 50 Input Voltage (V) FIGURE 2-8: Voltage. Output Voltage vs. Input +90°C FIGURE 2-11: Current. 150 250 VOUT = 5.0V 5.03 +130°C 5.02 5.00 -45°C 0°C 4.98 200 Output Voltage vs. Load 5.04 Output Voltage (V) 5.04 100 Load Current (mA) VOUT = 5.0V ILOAD = 0.1 mA 5.06 Output Voltage (V) 80 Output Voltage vs. Load 2.83 2.83 2.82 FIGURE 2-10: Current. Output Voltage (V) Output Voltage (V) Output Voltage vs. Input VOUT = 2.8V ILOAD = 0.1 mA 2.84 60 Load Current (mA) Input Voltage (V) FIGURE 2-7: Voltage. 40 +25°C +130°C 5.02 +90°C 5.01 5.00 4.99 0°C 4.98 4.97 4.96 -45°C +25°C 4.96 6 7 8 9 10 11 12 13 14 0 Input Voltage (V) FIGURE 2-9: Voltage. DS22008B-page 6 Output Voltage vs. Input 50 100 150 200 250 Load Current (mA) FIGURE 2-12: Current. Output Voltage vs. Load © 2007 Microchip Technology Inc. MCP1702 Note: Unless otherwise indicated: VR = 2.8V, COUT = 1 µF Ceramic (X7R), CIN = 1 µF Ceramic (X7R), IL = 100 µA, TA = +25°C, VIN = VOUT(MAX) + VDROPOUT(MAX). Dropout Voltage (V) 1.40 VOUT = 1.8V 1.30 +130°C +90°C 1.20 +25°C 1.10 1.00 0°C 0.90 -45°C 0.80 0.70 0.60 100 120 140 160 180 200 Load Current (mA) Dropout Voltage (V) FIGURE 2-13: Current. Dropout Voltage vs. Load 1.00 0.90 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 0.00 FIGURE 2-16: Dynamic Line Response. FIGURE 2-17: Dynamic Line Response. VOUT = 2.8V +130°C +90°C +25°C +0°C -45°C 0 25 50 75 100 125 150 175 200 225 250 Load Current (mA) Dropout Voltage vs. Load 0.50 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 VOUT = 5.0V +130°C +90°C +25°C +0°C -45°C 0 25 50 75 100 125 150 175 200 225 250 600.00 Short Circuit Current (mA) Dropout Voltage (V) FIGURE 2-14: Current. VOUT = 2.8V ROUT < 0.1 500.00 400.00 300.00 200.00 100.00 0.00 4 Dropout Voltage vs. Load © 2007 Microchip Technology Inc. 8 10 12 14 Input Voltage (V) Load Current (mA) FIGURE 2-15: Current. 6 FIGURE 2-18: Input Voltage. Short Circuit Current vs. DS22008B-page 7 MCP1702 0.20 0.15 0.10 0.05 0.00 -0.05 -0.10 -0.15 -0.20 -0.25 -0.30 0.20 VIN = 6V VIN = 4V VIN = 10V Line Regulation (%/V) Load Regulation (%) Note: Unless otherwise indicated: VR = 2.8V, COUT = 1 µF Ceramic (X7R), CIN = 1 µF Ceramic (X7R), IL = 100 µA, TA = +25°C, VIN = VOUT(MAX) + VDROPOUT(MAX). VIN = 12V VIN = 13.2V VOUT = 1.2V ILOAD = 0.1 mA to 200 mA VOUT = 1.2V VIN = 2.7V to 13.2V 0.16 0.12 1 mA 0.08 0 mA 0.04 100 mA 0.00 -45 -20 5 30 55 80 105 130 -45 -20 5 Temperature (°C) 0.40 0.30 0.20 0.10 0.00 -0.10 -0.20 -0.30 -0.40 -0.50 -0.60 Temperature. VOUT = 2.8V ILOAD = 1 mA to 250 mA VIN = 6V VIN = 10V VIN = 3.8V 105 130 VIN = 13.2V 0.20 0.16 VOUT = 2.8V VIN = 3.8V to 13.2V 250 mA 200 mA 0.12 0.08 0 mA 100 mA 0.04 0.00 -45 -20 5 30 55 80 105 130 -45 -20 5 Temperature (°C) 0.40 0.30 Temperature. VOUT = 5.0V ILOAD = 1 mA to 250 mA VIN = 6V 0.20 0.10 VIN = 10V VIN = 8V 0.00 55 80 105 130 Line Regulation vs. FIGURE 2-23: VIN = 13.2V -0.10 0.16 Line Regulation (%/V) Temperature. 30 Temperature (°C) Load Regulation vs. FIGURE 2-20: Load Regulation (%) 80 Line Regulation vs. FIGURE 2-22: Line Regulation (%/V) Load Regulation (%) Temperature. 55 Temperature (°C) Load Regulation vs. FIGURE 2-19: 30 0.14 VOUT = 5.0V VIN = 6.0V to 13.2V 0.12 0 mA 200 mA 250 mA 0.10 0.08 100 mA 0.06 -45 -20 5 30 55 80 105 130 -45 -20 Temperature (°C) FIGURE 2-21: Temperature. DS22008B-page 8 Load Regulation vs. 5 30 55 80 105 130 Temperature (°C) FIGURE 2-24: Temperature. Line Regulation vs. © 2007 Microchip Technology Inc. MCP1702 Note: Unless otherwise indicated: VR = 2.8V, COUT = 1 µF Ceramic (X7R), CIN = 1 µF Ceramic (X7R), IL = 100 µA, TA = +25°C, VIN = VOUT(MAX) + VDROPOUT(MAX). 0 PSRR (dB) -10 -20 -30 -40 -50 -60 VR=1.2V COUT=1.0 μF ceramic X7R VIN=2.7V CIN=0 μF IOUT=1.0 mA -70 -80 -90 0.01 0.1 1 10 Frequency (kHz) 100 1000 FIGURE 2-25: Power Supply Ripple Rejection vs. Frequency. FIGURE 2-28: Power Up Timing. FIGURE 2-29: Dynamic Load Response. FIGURE 2-30: Dynamic Load Response. 0 PSRR (dB) -10 -20 -30 -40 -50 -60 VR=5.0V COUT=1.0 μF ceramic X7R VIN=6.0V CIN=0 μF IOUT=1.0 mA -70 -80 -90 0.01 0.1 1 10 Frequency (kHz) 100 1000 FIGURE 2-26: Power Supply Ripple Rejection vs. Frequency. 100 VR=5.0V, VIN=6.0V IOUT=50 mA Noise (μV/ H ¥ z) 10 1 VR=2,8V, VIN=3.8V 0.1 VR=1.2V, VIN=2.7V 0.01 0.001 0.01 FIGURE 2-27: 0.1 1 10 Frequency (kHz) 100 1000 Output Noise vs. Frequency. © 2007 Microchip Technology Inc. DS22008B-page 9 MCP1702 3.0 PIN DESCRIPTIONS The descriptions of the pins are listed in Table 3-1. TABLE 3-1: PIN FUNCTION TABLE Pin No. SOT-23A Pin No. SOT-89 Pin No. TO-92 Symbol 1 1 1 GND Ground Terminal 2 3 3 VOUT Regulated Voltage Output 3 2, Tab 2 VIN Unregulated Supply Voltage – – – NC No connection 3.1 Ground Terminal (GND) Regulator ground. Tie GND to the negative side of the output and the negative side of the input capacitor. Only the LDO bias current (2.0 µA typical) flows out of this pin; there is no high current. The LDO output regulation is referenced to this pin. Minimize voltage drops between this pin and the negative side of the load. 3.2 Regulated Output Voltage (VOUT) Connect VOUT to the positive side of the load and the positive terminal of the output capacitor. The positive side of the output capacitor should be physically located as close to the LDO VOUT pin as is practical. The current flowing out of this pin is equal to the DC load current. DS22008B-page 10 Function 3.3 Unregulated Input Voltage Pin (VIN) Connect VIN to the input unregulated source voltage. Like all LDO linear regulators, low source impedance is necessary for the stable operation of the LDO. The amount of capacitance required to ensure low source impedance will depend on the proximity of the input source capacitors or battery type. For most applications, 1 µF of capacitance will ensure stable operation of the LDO circuit. For applications that have load currents below 100 mA, the input capacitance requirement can be lowered. The type of capacitor used can be ceramic, tantalum or aluminum electrolytic. The low ESR characteristics of the ceramic will yield better noise and PSRR performance at highfrequency. © 2007 Microchip Technology Inc. MCP1702 4.0 DETAILED DESCRIPTION 4.1 Output Regulation 4.3 A portion of the LDO output voltage is fed back to the internal error amplifier and compared with the precision internal bandgap reference. The error amplifier output will adjust the amount of current that flows through the P-Channel pass transistor, thus regulating the output voltage to the desired value. Any changes in input voltage or output current will cause the error amplifier to respond and adjust the output voltage to the target voltage (refer to Figure 4-1). 4.2 Overtemperature The internal power dissipation within the LDO is a function of input-to-output voltage differential and load current. If the power dissipation within the LDO is excessive, the internal junction temperature will rise above the typical shutdown threshold of 150°C. At that point, the LDO will shut down and begin to cool to the typical turn-on junction temperature of 130°C. If the power dissipation is low enough, the device will continue to cool and operate normally. If the power dissipation remains high, the thermal shutdown protection circuitry will again turn off the LDO, protecting it from catastrophic failure. Overcurrent The MCP1702 internal circuitry monitors the amount of current flowing through the P-Channel pass transistor. In the event of a short-circuit or excessive output current, the MCP1702 will turn off the P-Channel device for a short period, after which the LDO will attempt to restart. If the excessive current remains, the cycle will repeat itself. MCP1702 VOUT VIN Error Amplifier +VIN Voltage Reference + Overcurrent Overtemperature GND FIGURE 4-1: Block Diagram. © 2007 Microchip Technology Inc. DS22008B-page 11 MCP1702 5.0 FUNCTIONAL DESCRIPTION The MCP1702 CMOS LDO linear regulator is intended for applications that need the lowest current consumption while maintaining output voltage regulation. The operating continuous load range of the MCP1702 is from 0 mA to 250 mA (VR ≥ 2.5V). The input operating voltage range is from 2.7V to 13.2V, making it capable of operating from two or more alkaline cells or single and multiple Li-Ion cell batteries. 5.1 Input The input of the MCP1702 is connected to the source of the P-Channel PMOS pass transistor. As with all LDO circuits, a relatively low source impedance (10Ω) is needed to prevent the input impedance from causing the LDO to become unstable. The size and type of the capacitor needed depends heavily on the input source type (battery, power supply) and the output current range of the application. For most applications (up to 100 mA), a 1 µF ceramic capacitor will be sufficient to ensure circuit stability. Larger values can be used to improve circuit AC performance. DS22008B-page 12 5.2 Output The maximum rated continuous output current for the MCP1702 is 250 mA (VR ≥ 2.5V). For applications where VR < 2.5V, the maximum output current is 200 mA. A minimum output capacitance of 1.0 µF is required for small signal stability in applications that have up to 250 mA output current capability. The capacitor type can be ceramic, tantalum or aluminum electrolytic. The esr range on the output capacitor can range from 0Ω to 2.0Ω. 5.3 Output Rise time When powering up the internal reference output, the typical output rise time of 500 µs is controlled to prevent overshoot of the output voltage. There is also a startup delay time that ranges from 300 µs to 800 µs based on loading. The startup time is separate from and precedes the Output Rise Time. The total output delay is the Startup Delay plus the Output Rise time. © 2007 Microchip Technology Inc. MCP1702 6.0 APPLICATION CIRCUITS AND ISSUES 6.1 The MCP1702 is most commonly used as a voltage regulator. It’s low quiescent current and low dropout voltage makes it ideal for many battery-powered applications. GND VIN VIN (2.8V to 3.2V) VOUT COUT 1 µF Ceramic FIGURE 6-1: 6.1.1 CIN 1 µF Ceramic Typical Application Circuit. = PTOTAL = Package Type = SOT-23A VIN maximum = 3.2V VOUT typical = 1.8V IOUT = 150 mA maximum Power Calculations 6.2.1 Maximum continuous junction temperature Total device power dissipation RθJA Thermal resistance from junction to ambient = Maximum ambient temperature The maximum power dissipation capability for a package can be calculated given the junction-toambient thermal resistance and the maximum ambient temperature for the application. The following equation can be used to determine the package maximum internal power dissipation. EQUATION 6-3: APPLICATION INPUT CONDITIONS Input Voltage Range = 2.8V to 3.2V 6.2 TJ(MAX) TAMAX MCP1702 IOUT 150 mA T J ( MAX ) = P TOTAL × Rθ JA + T AMAX Where: Typical Application VOUT 1.8V EQUATION 6-2: Where: ( T J ( MAX ) – T A ( MAX ) ) P D ( MAX ) = --------------------------------------------------Rθ JA PD(MAX) = Maximum device power dissipation TJ(MAX) = Maximum continuous junction temperature TA(MAX) RθJA Maximum ambient temperature = Thermal resistance from junction to ambient POWER DISSIPATION The internal power dissipation of the MCP1702 is a function of input voltage, output voltage and output current. The power dissipation, as a result of the quiescent current draw, is so low, it is insignificant (2.0 µA x VIN). The following equation can be used to calculate the internal power dissipation of the LDO. EQUATION 6-4: T J ( RISE ) = P D ( MAX ) × Rθ JA Where: TJ(RISE) = Rise in device junction temperature over the ambient temperature PTOTAL = Maximum device power dissipation EQUATION 6-1: P LDO = ( V IN ( MAX ) ) – V OUT ( MIN ) ) × I OUT ( MAX ) ) Where: PLDO = LDO Pass device internal power dissipation VIN(MAX) = Maximum input voltage VOUT(MIN) = LDO minimum output voltage The maximum continuous operating junction temperature specified for the MCP1702 is +125°C. To estimate the internal junction temperature of the MCP1702, the total internal power dissipation is multiplied by the thermal resistance from junction to ambient (RθJA). The thermal resistance from junction to ambient for the SOT-23A pin package is estimated at 336°C/W. © 2007 Microchip Technology Inc. RθJA Thermal resistance from junction to ambient EQUATION 6-5: T J = T J ( RISE ) + T A Where: TJ = Junction Temperature TJ(RISE) = Rise in device junction temperature over the ambient temperature TA Ambient temperature DS22008B-page 13 MCP1702 6.3 Voltage Regulator Internal power dissipation, junction temperature rise, junction temperature and maximum power dissipation are calculated in the following example. The power dissipation, as a result of ground current, is small enough to be neglected. 6.3.1 Junction Temperature Estimate To estimate the internal junction temperature, the calculated temperature rise is added to the ambient or offset temperature. For this example, the worst-case junction temperature is estimated below. POWER DISSIPATION EXAMPLE Package Package Type = SOT-23A = TJRISE + TA(MAX) TJ = 113.3°C Maximum Package Power Dissipation at +40°C Ambient Temperature 2.8V to 3.2V LDO Output Voltages and Currents VOUT = 1.8V IOUT = 150 mA Maximum Ambient Temperature TA(MAX) = SOT-23 (336.0°C/Watt = RθJA) Input Voltage VIN TJ = +40°C PLDO(MAX) = (VIN(MAX) - VOUT(MIN)) x IOUT(MAX) PLDO = (3.2V - (0.97 x 1.8V)) x 150 mA PLDO = 218.1 milli-Watts Device Junction Temperature Rise The internal junction temperature rise is a function of internal power dissipation and the thermal resistance from junction to ambient for the application. The thermal resistance from junction to ambient (RθJA) is derived from an EIA/JEDEC standard for measuring thermal resistance for small surface mount packages. The EIA/ JEDEC specification is JESD51-7, “High Effective Thermal Conductivity Test Board for Leaded Surface Mount Packages”. The standard describes the test method and board specifications for measuring the thermal resistance from junction to ambient. The actual thermal resistance for a particular application can vary depending on many factors, such as copper area and thickness. Refer to AN792, “A Method to Determine How Much Power a SOT-23 Can Dissipate in an Application”, (DS00792), for more information regarding this subject. TJ(RISE) = PTOTAL x RqJA TJRISE = 218.1 milli-Watts x 336.0°C/Watt TJRISE = 73.3°C DS22008B-page 14 = (125°C - 40°C) / 336°C/W PD(MAX) = 253 milli-Watts SOT-89 (52°C/Watt = RθJA) PD(MAX) = (125°C - 40°C) / 52°C/W PD(MAX) = 1.635 Watts TO92 (131.9°C/Watt = RθJA) Internal Power Dissipation Internal Power dissipation is the product of the LDO output current times the voltage across the LDO (VIN to VOUT). PD(MAX) 6.4 PD(MAX) = (125°C - 40°C) / 131.9°C/W PD(MAX) = 644 milli-Watts Voltage Reference The MCP1702 can be used not only as a regulator, but also as a low quiescent current voltage reference. In many microcontroller applications, the initial accuracy of the reference can be calibrated using production test equipment or by using a ratio measurement. When the initial accuracy is calibrated, the thermal stability and line regulation tolerance are the only errors introduced by the MCP1702 LDO. The low-cost, low quiescent current and small ceramic output capacitor are all advantages when using the MCP1702 as a voltage reference. Ratio Metric Reference 2 µA Bias MCP1702 VIN CIN VOUT 1 µF GND PIC® Microcontroller COUT 1 µF VREF ADO AD1 Bridge Sensor FIGURE 6-2: voltage reference. Using the MCP1702 as a © 2007 Microchip Technology Inc. MCP1702 6.5 Pulsed Load Applications For some applications, there are pulsed load current events that may exceed the specified 250 mA maximum specification of the MCP1702. The internal current limit of the MCP1702 will prevent high peak load demands from causing non-recoverable damage. The 250 mA rating is a maximum average continuous rating. As long as the average current does not exceed 250 mA, pulsed higher load currents can be applied to the MCP1702. The typical current limit for the MCP1702 is 500 mA (TA +25°C). © 2007 Microchip Technology Inc. DS22008B-page 15 MCP1702 7.0 PACKAGING INFORMATION 7.1 Package Marking Information 3-Pin SOT-23A Example: Standard Extended Temp Symbol XXNN Voltage * Symbol Voltage * HA 1.2 HF 3.0 HB 1.5 HG 3.3 HC 1.8 HH 4.0 HD 2.5 HJ 5.0 HE 2.8 — — * Custom output voltages available upon request. Contact your local Microchip sales office for more information. 3-Lead SOT-89 HANN Example Standard Extended Temp XXXYYWW NNN Symbol Voltage * HA0619 256 Example 1702 1202E e3 TO^^ 619256 XXXXXX XXXXXX XXXXXX YWWNNN Legend: XX...X Y YY WW NNN e3 * DS22008B-page 16 Symbol HA 1.2 HF 3.0 HB 1.5 HG 3.3 HC 1.8 HH 4.0 HD 2.5 HJ 5.0 HE 2.8 — — * Custom output voltages available upon request. Contact your local Microchip sales office for more information. 3-Lead TO-92 Note: Voltage * Customer-specific information Year code (last digit of calendar year) Year code (last 2 digits of calendar year) Week code (week of January 1 is week ‘01’) Alphanumeric traceability code Pb-free JEDEC designator for Matte Tin (Sn) This package is Pb-free. The Pb-free JEDEC designator ( e3 ) can be found on the outer packaging for this package. In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line, thus limiting the number of available characters for customer-specific information. © 2007 Microchip Technology Inc. MCP1702 3-Lead Plastic Small Outline Transistor (CB) [SOT-23A] Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging D e1 e 2 1 E E1 N b A c A2 φ L A1 Units Dimension Limits Number of Pins MILLIMETERS MIN NOM MAX N 3 Lead Pitch e 0.95 BSC Outside Lead Pitch e1 Overall Height A 0.89 – Molded Package Thickness A2 0.90 – 1.30 Standoff A1 0.00 – 0.15 Overall Width E 2.10 – 3.00 Molded Package Width E1 1.20 – 1.80 Overall Length D 2.70 – 3.10 Foot Length L 0.15 – 0.60 Foot Angle φ 0° – 30° Lead Thickness c 0.09 – 0.26 1.90 BSC 1.45 Lead Width b 0.30 – 0.51 Notes: 1. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.127 mm per side. 2. Dimensioning and tolerancing per ASME Y14.5M. BSC: Basic Dimension. Theoretically exact value shown without tolerances. Microchip Technology Drawing C04-130B © 2007 Microchip Technology Inc. DS22008B-page 17 MCP1702 3-Lead Plastic Small Outline Transistor Header (MB) [SOT-89] Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging D D1 E H L 1 N 2 b b1 b1 e E1 e1 A C Units Dimension Limits Number of Leads MILLIMETERS MIN N MAX 3 Pitch e 1.50 BSC Outside Lead Pitch e1 3.00 BSC Overall Height A 1.40 1.60 Overall Width H 3.94 4.25 Molded Package Width at Base E 2.29 2.60 Molded Package Width at Top E1 2.13 2.29 Overall Length D 4.39 4.60 Tab Length D1 1.40 1.83 Foot Length L 0.79 1.20 Lead Thickness c 0.35 0.44 Lead 2 Width b 0.41 0.56 Leads 1 & 3 Width b1 0.36 0.48 Notes: 1. Dimensions D and E do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.127 mm per side. 2. Dimensioning and tolerancing per ASME Y14.5M. BSC: Basic Dimension. Theoretically exact value shown without tolerances. Microchip Technology Drawing C04-029B DS22008B-page 18 © 2007 Microchip Technology Inc. MCP1702 3-Lead Plastic Transistor Outline (TO) [TO-92] Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging E A N 1 L 1 2 3 b e c D R Units Dimension Limits Number of Pins INCHES MIN N MAX 3 Pitch e Bottom to Package Flat D .125 .050 BSC .165 Overall Width E .175 .205 Overall Length A .170 .210 Molded Package Radius R .080 .105 Tip to Seating Plane L .500 – Lead Thickness c .014 .021 Lead Width b .014 .022 Notes: 1. Dimensions A and E do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .005" per side. 2. Dimensioning and tolerancing per ASME Y14.5M. BSC: Basic Dimension. Theoretically exact value shown without tolerances. Microchip Technology Drawing C04-101B © 2007 Microchip Technology Inc. DS22008B-page 19 MCP1702 NOTES: DS22008B-page 20 © 2007 Microchip Technology Inc. MCP1702 APPENDIX A: REVISION HISTORY Revision B (May 2007) • All Pages: Corrected minor errors in document. • Page 4: Added junction-to-case information to Temperature Specifications table. • Page 16: Updated Package Outline Drawings in Section 7.0 “Packaging Information”. • Page 21: Updated Revison History. • Page 23: Corrected examples in ”Product Identification System”. Revision A (September 2006) • Original Release of this Document. © 2007 Microchip Technology Inc. DS22008B-page 21 MCP1702 NOTES: DS22008B-page 22 © 2007 Microchip Technology Inc. MCP1702 PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office. PART NO. Device X- XX X X X/ XX Tape Output Feature Tolerance Temp. Package and Reel Voltage Code Device: MCP1702: 2 µA Low Dropout Positive Voltage Regulator Tape and Reel: T Output Voltage *: 12 = 1.2V “Standard” 15 = 1.5V “Standard” 18 = 1.8V “Standard” 25 = 2.5V “Standard” 28 = 2.8V “Standard” 30 = 3.0V “Standard” 33 = 3.3V “Standard” 40 = 4.0V “Standard” 50 = 5.0V “Standard” *Contact factory for other output voltage options. = Tape and Reel Extra Feature Code: 0 = Fixed Tolerance: 2 = 2.0% (Standard) Temperature: E = -40°C to +125°C Package Type: CB = 3-Pin SOT-23A (equivalent to EIAJ SC-59) MB = 3-Pin SOT-89 TO = 3-Pin TO-92 © 2007 Microchip Technology Inc. Examples: a) MCP1702T-1202E/CB: 1.2V LDO Positive Voltage Regulator, SOT-23A-3 pkg. b) MCP1702T-1802E/MB: 1.8V LDO Positive Voltage Regulator, SOT-89-3 pkg. c) MCP1702T-2502E/CB: 2.5V LDO Positive Voltage Regulator, SOT-23A-3 pkg. d) MCP1702T-3002E/CB: 3.0V LDO Positive Voltage Regulator, SOT-23A-3 pkg. e) MCP1702T-3002E/MB: 3.0V LDO Positive Voltage Regulator, SOT-89-3 pkg. f) MCP1702T-3302E/CB: 3.3V LDO Positive Voltage Regulator, SOT-23A-3 pkg. g) MCP1702T-3302E/MB: 3.3V LDO Positive Voltage Regulator, SOT-89-3 pkg. h) MCP1702T-4002E/CB: 4.0V LDO Positive Voltage Regulator, SOT-23A-3 pkg. i) MCP1702-5002E/TO: j) MCP1702T-5002E/CB: 5.0V LDO Positive Voltage Regulator, SOT-23A-3 pkg. k) MCP1702T-5002E/MB: 5.0V LDO Positive Voltage Regulator, SOT-89-3 pkg. 5.0V LDO Positive Voltage Regulator, TO-92 pkg. DS22008B-page 23 MCP1702 NOTES: DS22008B-page 24 © 2007 Microchip Technology Inc. Note the following details of the code protection feature on Microchip devices: • Microchip products meet the specification contained in their particular Microchip Data Sheet. • Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions. • There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft of intellectual property. • Microchip is willing to work with the customer who is concerned about the integrity of their code. • Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable.” Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act. Information contained in this publication regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights. Trademarks The Microchip name and logo, the Microchip logo, Accuron, dsPIC, KEELOQ, KEELOQ logo, microID, MPLAB, PIC, PICmicro, PICSTART, PRO MATE, PowerSmart, rfPIC, and SmartShunt are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. AmpLab, FilterLab, Linear Active Thermistor, Migratable Memory, MXDEV, MXLAB, PS logo, SEEVAL, SmartSensor and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. Analog-for-the-Digital Age, Application Maestro, CodeGuard, dsPICDEM, dsPICDEM.net, dsPICworks, ECAN, ECONOMONITOR, FanSense, FlexROM, fuzzyLAB, In-Circuit Serial Programming, ICSP, ICEPIC, Mindi, MiWi, MPASM, MPLAB Certified logo, MPLIB, MPLINK, PICkit, PICDEM, PICDEM.net, PICLAB, PICtail, PowerCal, PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, rfPICDEM, Select Mode, Smart Serial, SmartTel, Total Endurance, UNI/O, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. © 2007, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. Microchip received ISO/TS-16949:2002 certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona, Gresham, Oregon and Mountain View, California. The Company’s quality system processes and procedures are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping devices, Serial EEPROMs, microperipherals, nonvolatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001:2000 certified. © 2007 Microchip Technology Inc. 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