www.fairchildsemi.com ILC6376/77 0.5A, 300kHz, SO-8 PWM/PFM Step Down Converter with Shutdown Features Description • • • • • • • • • • The ILC6376/77 is a 95% efficient, 300kHz step-down DCDC converter in an SO-8 package; capable of delivering 500mA output current. The device is also capable of driving an external FET for higher output current applications. ±2.5% accurate output voltages Guaranteed 500mA output current 95% efficiency 55µA no load battery input current (ILC6377) 1.5µA shutdown current Built in short circuit and overcurrent protection Undervoltage lockout and soft-start External transistor drive available for higher IOUT 300kHz operation Automatic switchover to PFM mode at low currents for longest battery life (ILC6377) • Fixed 3.3V or 5V or adjustable output • SO-8 package Applications • • • • Cellular Phones Palmtops and PDAs Portable Instrumentation Buck Converter for Industrial / Networking Applications The ILC6376/77 uses a unique p-channel architecture with built-in charge pump to maintain low on-resistance, even at low input voltages. The ILC6376 operates in PWM mode with 300kHz switching frequency. The ILC6377 does the same at high and medium load currents. When the load current drops and the device hits approximately 25% duty cycle, ILC6377 automatically switches over to PFM or pulse skipping mode. PFM (pulse frequency modulation) mode of operation extends efficiency at light loads. Start-up is controlled via an external soft-start capacitor. The device will automatically re-enter start-up mode when an output current overload condition is sensed; thus providing automatic short-circuit protection. Voltage lockout prevents faulty operation below the minimum operating voltage level. In shutdown, the ILC6376/77 consumes only 1.5µA current. The ILC6376/77SOXX offers fixed 3.3V or 5V output while ILC6376/77SOADJ allows adjustable output. Both versions of ILC6376/77 are available in an SO-8 surface mount package. Typical Applications SD1 VIN 1 *CIN S/D 10µF 8 + 2 ILC6376/77 3 4 CSS (TOP VIEW) L 22µH 7 6 VOUT 5 + CL 47µF Fig 1. Typical step-down DC-DC converter application SD1: SS12 Schottky Diode (FAIRCHILD) CL: 10V/47µF Tantalum Capacitor (NICHICON, F93) CSS: 4700pF Ceramic Capacitor CIN: 16V / 10µF Tantalum Capacitor (NICHICON, F93) Rev. 1.5 November 2001 ©2001 Fairchild Semiconductor Corporation ILC6376/77 Pin Assignments VIN 1 8 LX VIN 1 EXT2 2 7 EXT1 EXT2 2 P_BST 3 6 GND P_BST 3 S/D, CSS 4 5 VOUT S/D, CSS 4 ILC6376/77 (TOP VIEW) ILC6376/77 SOXX SO-8 Package ILC6376/77 (TOP VIEW) 8 LX 7 EXT1 6 GND 5 FB ILC6376/77 SOADJ SO-8 Package Pin Definitions Pin Symbol 1 VIN Function 2 EXT2 External gate drive pin (low when P-Ch FET is ON) 3 P-BST P-Ch gate boost 4 S/D, Power Supply Shutdown, also soft-start capacitor pin and VREFoutput Softstart, VREF 5 VOUT / FB 6 GND 7 EXT1 8 LX Output voltage sense pin for ILC6376/77SO-XX; 1V feedback pin for ILC6376/77SO-ADJ Ground connection External gate drive pin (low when P-Ch FET is ON) Inductor Switch Pin Internal Block Diagram VIN VOUT 8 LX 1 5 7 EXT1 + Error Amp - S/D, 4 Softstart, Vref S/D, Vref with Softstart + PWM Comp - GATE DRIVER 2 EXT2 3 P_BST Protection PWM/PFM CONTROLLER RAMP WAVE GENERATOR, OSCILLATOR 6 GND ©2001 Fairchild Semiconductor Corporation 2 ILC6376/77 Absolute Maximum Ratings (TA=25°C) Parameter VIN Input Voltage Pin Symbol Ratings Units VIN -0.3 to +12 V VOUT VFB -0.3 to +12 -0.3 to VIN +0.3 V Voltage on LX pin VLX VIN - VLX = -0.3 to +12 V Peak Switch Current on LX pin ILX 700 mA VDP_BST VIN - VP_BST = -0.3 to +12 V VOUT Pin (ILC6376/77SOXX) FB Pin (ILC6376/77SOADJ) Voltage on P_BST pin Current EXT1, EXT2 pins IEXT1, IEXT2 ±50 mA Voltage on all other pins ~ -0.3 to VIN + 0.3 V PD 300 mW Operating Ambient Temperature TOPR -30~+80 °C Storage Temperature TSTG -40~+125 °C Continuous Total Power Dissipation Electrical Characteristics ILC6376/77SO33 VOUT = 3.3V, VIN = 4V, FOSC=300kHz, IOUT = 130mA, TA = 25°C, unless otherwise specified. Circuit configuration figure 1. Parameter Output Voltage Input Voltage Output Maximum Current Input Current Supply Symbol VOUT VIN IOUT(MAX) IIN Shutdown Current LX Switch On - Resistance IS/D Rds(on) LX Switch Leakage Current ILXL Oscillator Frequency FOSC Max Duty Cycle PFM Duty Cycle Efficiency Undervoltage Lockout MAXDTY PFMDTY EFFI VUVLO Soft-Start Time Shutdown Input Voltage EXT1, EXT2 Hi OnResistance EXT1, EXT2 Low OnResistance TSS VSD REXtHI REXtLOW Conditions VIN 3.5V, No Loads Min. 3.218 Typ. 3.300 500 600 1480 50 1.5 0.64 ILC6376 ILC6377 VS/D = 0V Open Loop Measurement, VS/D = VIN, VLX = VIN - 0.2V, VOUT = 3V Open Loop Measurement, VOUT = VIN, VLX = 0V Measurement Waveform at EXT pin VIN = 3.6V IOUT = 20mA Max. 3.383 10 2190 86 2.5 0.85 µA µA Ω 2.0 µA kHz 255 300 345 No Load (ILC6377) 15 100 25 95 35 Minimum VIN when Vref does not start up VREF rises to 0V from 0.9V High = Regulator “ON” Low = Regulator “OFF” 3V applied to VOUT with no external components 3.6V applied to VOUT with no external components 0.9 6.0 0.65 Units V V mA 1.8 % % % V 10.0 16.0 msec V 35 0.2 47 Ω 29 37 Ω ©2001 Fairchild Semiconductor Corporation 3 ILC6376/77 Electrical Characteristics ILC6376/77SO50 Unless Otherwise specified all limits are at VOUT = 5.0V, VIN = 6V, FOSC=300kHz, IOUT = 200mA, TA = 25°C. Circuit configuration figure 1. Parameter Output Voltage Input Voltage Output Maximum Current Symbol Conditions Units V 10 V 3740 ILC6377 71 110 VS/D = 0V 1.5 2.5 µA Open Loop Measurement, VS/D = VIN, VLX =VIN - 0.2V, VOUT = 4.5V 0.44 0.58 Ω 2.0 µA 345 kHz IS/D ILXL FOSC Max Duty Cycle MAXDTY PFM Duty Cycle PFMDTY Efficiency EFFI Undervoltage Lockout VUVLO Open Loop Measurement, VOUT = VIN, VLX = 0V Measure Waveform at EXT pin VIN = 5.3V IOUT = 20mA 255 No Load (ILC6377) 15 Minimum VIN when VREF does not start up 0.9 25 VREF rises to 0V from 0.9V 6.0 Shutdown Input Voltage VS/D High = Regulator “ON” Low = Regulator “OFF” 0.65 10.0 µA % 35 95 TSS EXT1, EXT2 Low OnResistance 300 100 Soft-Start Time EXT1, EXT2 Hi OnResistance mA 2540 Shutdown Current Rds(on) 600 ILC6376 VIN 5.25V, No Load Oscillator Frequency Max. 5.125 500 IOUT(MAX) IIN LX Switch Leakage Current Typ. 4.875 5.000 VIN Input Supply Current LX Switch On-Resistance Min. VOUT % % 1.8 V 16 msec V 0.2 REXtHI Open Loop Measurement 24 32 Ω REXtLOW Open Loop Measurement 20 26 Ω ©2001 Fairchild Semiconductor Corporation 4 ILC6376/77 Electrical Characteristics ILC6376/77SOADJ Unless Otherwise specified all limits are at VOUT programmed to 5.0V, VIN = 6V, FOSC=300kHz, IOUT = 200mA, TA = 25°C. Circuit configuration figure 1. Parameter Feedback Voltage (pin 5) Output Voltage Output Maximum Current Symbol Conditions VFB VOUT RFB1 + RFB2 < 2MΩ Min. Typ. Max. Units .995 1.000 1.015 V 1.5 500 IOUT(MAX) 6 600 V mA Input Supply Current IIN VIN 5.25V, No Load 71 110 µA Shutdown Current IS/D VS/D = 0V 1.5 2.5 µA Open Loop Measurement, VS/D = VIN, VLX = VIN - 0.2V, VOUT = 4.5V 0.44 0.58 Ω 2.0 µA 345 kHz LX Switch On-Resistance LX Leak Current Oscillator Frequency Rds(on) ILXL FOSC Max Duty Cycle MAXDTY PFM Duty Cycle PFMDTY Efficiency EFFI Undervoltage Lockout VUVLO Open Loop Measurement, VOUT = VIN, VLX = 0V Measure Waveform at EXT pin VIN = 5.3V IOUT = 20mA 255 100 No Load (ILC6377) 15 Minimum VIN when VREF does not start up 0.9 TSS VREF rises to 0V from 0.9V 6.0 Shutdown Input Voltage VS/D High = Regulator “ON” Low = Regulator “OFF” 0.65 EXT1, EXT2 Low OnResistance 25 % 35 95 Soft-Start Time EXT1, EXT2 Hi OnResistance 300 10.0 % % 1.8 V 16.0 msec V 0.2 REXtHI Open Loop Measurement 24 32 Ω REXtLOW Open Loop Measurement 20 26 Ω ©2001 Fairchild Semiconductor Corporation 5 ILC6376/77 SD1 VIN 1 *CIN S/D 10µF 8 + 2 ILC6376/77 3 (TOP VIEW) 4 CSS L 22µH 7 6 VOUT 5 + CL 47µF Fig 1. Typical step-down DC-DC converter application SD1: SS12 Schottky Diode (FAIRCHILD) CL: 10V/47µF Tantalum Capacitor (NICHICON, F93) CSS: 4700pF Ceramic Capacitor CIN: 16V / 10µF Tantalum Capacitor (NICHICON, F93) Figure 1 shows a typical fixed output voltage step-down DC-DC converter application circuit for ILC6376/77SOXX. External component selection Over-current and short-circuit protection Proper selection of external components is important for achieving high performance. The output inductor selected should have low DC resistance on the order of 0.2Ω or less and saturation current rating of 1A or higher. Recommended inductors are Sumida CD54 (22µH, 0.18Ω max DC resistance) or Coilcraft DO3308P-223 (22µH, 0.18Ω max DC resistance) or equivalent. In the event of an over-current or short-circuit condition, the ILC6376/77 cycles the soft-start pin in a hiccup mode to provide fault protection. When the output voltage decreases due to overload, the ILC6376/77 will operate continuously at the maximum duty cycle. If the period of maximum duty cycle operation exceeds TPRO (typically 5 msec), pin 4 will be pulled low; thus discharging the external soft-start capacitor CSS. This action inhibits the regulator’s PWM action. Next, the ILC6376/77’s soft-start circuitry starts recharging CSS and initiates a controlled start-up. If the overload condition continues to exist, the above sequence of events will repeat; thus continuing to cycle the soft-start function. The catch diode should be a schottky diode with low forward drop and rated at 1A or greater current, SS12 or it’s equivalent is recommended. Input and output capacitors should be tantalum capacitors with low equivalent series resistance (ESR) and voltage rating higher than the actual application. Soft-start Pin 4 of ILC6376/77 functions as the soft-start pin as well as the shutdown pin. A soft-start capacitor (from pin 4 to ground) controls the rate at which the power supply starts up; thus preventing large overshoots at the output as well as large in-rush current. The value for CSS should be 100pF or greater. Shutdown The ILC6376/77 is placed in shutdown mode by taking pin 4 to ground. In shutdown, the quiescent current of the device is under 2µA. When using the shutdown feature, pin 4 must be driven from an open collector or open drain output without employing an external pull-up resistor, as shown in figure 2. Note that very little power is dissipated with this method of fault protection versus constant current limit protection. Even though the internal power MOSFET is pulsed on and off at high peak current, the DC current is low; thus leading to low power dissipation even under short-circuit conditions. Keep in mind that the duration of maximum duty cycle condition is used to trigger the ILC6376/77’s fault protection circuit. As such, a small input-output (V IN - VOUT) differential voltage may trigger the device’s fault protection circuitry even at low output current. Undervoltage Lockout The undervoltage lockout feature prevents faulty operation by disabling the operation of the regulator when input voltage is below the minimum operating voltage, VUVLO. When the input voltage is lower than VUVLO the device disables the internal P-channel MOSFET and provides “high” output at both EXT1 and EXT2 outputs. ©2001 Fairchild Semiconductor Corporation 6 ILC6376/77 To pin 8 EXT1 SD1 VIN *CIN 1 + 2 S/D VOUT 8 ILC6376/77 3 (TOP VIEW) 4 6 L 7 CFB RFB1 5 6 RFB2 VOUT 5 + CSS CL Fig.2 1Amp output current application using external MOSFET The EXT1 and EXT2 pins are provided so as to drive external transistors; thus allowing design flexibility. The EXT1 output drive signal has the same timing as the gate drive to the internal P-channel MOSFET i.e. EXT1 output is low as long as the internal MOSFET is on. Both EXT1 and EXT2 pins are capable of driving 1000pF gate capacitance. For example, a high output current application circuit using an external P-channel MOSFET is shown in figure 2. RFB1 + RFB2 < 2MW 1 C FB chosen so that 1kHz < 2 x π x CFB x RFB1 < 20kHz Fig.4 Adjustable output using ILC6376/77SOADJ (Note: rest of circuit is same as Fig.1) Adjustable Output (ILC6376/77SOADJ) For adjustable output voltage ILC6376/77SOADJ should be used. All connections to the ILC6376/77SOADJ are the same as ILC6376/77SOXX, except for the feedback voltage divider network shown in figure 4. The output voltage, VOUT, can be calculated from the following equation: VOUT = VFB (1 + RFB1/RFB2), where VFB is approximately 1V and RFB1 + RFB2 < 2MΩ 1 CBST 2200pF 2 3 8 ILC6376/77 (TOP VIEW) 4 SD2 MBR0520L Schottky 7 6 5 Voltage between Vin and P_BST must be less than 10V. Figure 3. P-Channel Negative Boost Circuit P-Channel Boost Circuit The ILC6376/77 includes a unique P-Channel MOSFET architecture with built-in charge pump to maintain low onresistance even at low input voltages. As shown in figure 3, a 2200pF ceramic capacitor and a schottky diode (MBR0520L or equivalent) allows the gate voltage of the internal P-Channel MOSFET to be driven negative; thus reducing the switch on-resistance. This technique can be employed to increase efficiency at low input voltages and high output currents. Note that the voltage between VIN and P_BST should not exceed 10V, otherwise damage to the device may occur. For high input voltage applications the schottky diode should be replaced by a low voltage zener diode so that the P_BST pin is clamped to a safe negative voltage. The feedback compensation capacitor should be chosen such that the pole frequency f is between 1kHz and 20kHz: 1 1kHz < 2 x π x CFB x RFB1 < 20kHz The pole frequency should generally be set at 5kHz. The value of CFB calculated from the above equation may require some adjustment depending on the output inductor (L) and output capacitor (CL) values chosen. Example for 3V output: RFB1 = 400kΩ RFB2 = 200kΩ CFB = 100pF PC Board Layout As with all switching DC-DC converter designs, good PC board layout is critical for optimum performance. The heavy lines indicated in figure 1 schematic should be wide printed circuit board traces and should be kept as short as is practical. A large ground plane with as much copper area as is allowable should be used. All external components should be mounted as close to the IC as possible. For ILC6376/77SOADJ, the feedback resistors and their associated wiring should be kept away from the inductor location and the vicinity of inductive flux. ©2001 Fairchild Semiconductor Corporation 7 ILC6376/77 Typical Performance Characteristics General conditions for all curves: Circuit 1; L = 20µH (Sumida, CD54), CIN = 47µF (tantalum) with 0.1µF (ceramic), CL = 47µH (tantalum) SS12 schottky diode, CSS = 4700pF (ceramic), TA = 25°C unless otherwise noted. Output Voltage vs. Output Current Output Voltage vs. Output Current ILC6377SO33 L = 22µH (CD54) 3.5 3.4 5.0V VIN = 3.96 3.3 8.0V 3.2 3.1 OUTPUT VOLTAGE: VOUT(V) OUTPUT VOLTAGE: VOUT(V) 3.5 10.0V 3.4 3.3 VIN = 3.96V, 5.0V,8.0V 3.2 3.1 3.0 3.0 0.1 1 10 0.1 1000 100 5.0V VIN = 3.96 3.3 8.0V 3.2 3.1 3.5 OUTPUT VOLTAGE: VOUT(V) OUTPUT VOLTAGE: VOUT(V) L = 10µH (CD54) 3.4 0.1 ILC6377SO-33 L = 47µH (CD105) 3.4 5.0V VIN = 4.0V 3.3 3.2 8.0V 3.1 1 10 100 0.1 1000 Output Voltage vs. Output Current 10.0V OUTPUT VOLTAGE: VOUT(V) 5.4 5.2 10 1000 100 Output Voltage vs. Output Current L = 22µH (CD54) ILC6377SO50 1 OUTPUT CURRENT: IOUT(mA) OUTPUT CURRENT: IOUT(mA) OUTPUT VOLTAGE: VOUT(V) 1000 100 3.0 3.0 5.4 10 Output Voltage vs. Output Current Output Voltage vs. Output Current ILC6377SO33 1 OUTPUT CURRENT: IOUT(mA) OUTPUT CURRENT: IOUT(mA) 3.5 L = 22µH (CD54) ILC6376SO33 6.0V 5.0 8.0V 4.8 4.6 ILC6376SO50 L =22µH (CD54) 5.2 10.0V 5.0 6.0V 8.0V 4.8 4.6 4.4 4.4 0.1 1 10 100 OUTPUT CURRENT: IOUT(mA) 1000 0.1 1 10 100 1000 OUTPUT CURRENT: IOUT(mA) ©2001 Fairchild Semiconductor Corporation 8 ILC6376/77 Typical Performance Characteristics General conditions for all curves: Circuit 1; L = 20µH (Sumida, CD54), CIN = 47µF (tantalum) with 0.1µF (ceramic), CL = 47µH (tantalum) SS12 schottky diode, CSS = 4700pF (ceramic), TA = 25°C unless otherwise noted. Efficiency vs. Output Current Efficiency vs. Output Current L = 22µH (CD54) ILC6377SO33 100 100 ILC6376SO33 EFFICIENCY: EFFI(%) EFFICIENCY: EFFI(%) VIN = 4.0V 80 5.0V 8.0V 60 40 20 0 0.1 1 10 VIN = 4.0V 10.0V 60 8.0V 40 20 1 10 1000 100 OUTPUT CURRENT: IOUT(mA) OUTPUT CURRENT: IOUT(mA) Efficiency vs. Output Current Efficiency vs. Output Current L = 10µH (CD54) ILC6377SO33 100 80 0 0.1 1000 100 L = 22µH (CD54) 5.0V 100 L = 47µH (CD105) ILC6377SO33 80 EFFICIENCY: EFFI(%) EFFICIENCY: EFFI(%) VIN = 3.96V 5.0V 8.0V 60 40 20 0 0.1 1 10 5.0V 60 40 20 L = 22µH (CD54) 100 EFFICIENCY: EFFI(%) EFFICIENCY: EFFI(%) 100 1000 L = 22µH (CD54) ILC6376SO50 5.0V 80 10.0 8.0V VIN = 6.0V 60 40 20 0 0.1 10 Efficiency vs. Output Current Efficiency vs. Output Current ILC6377SO50 1 OUTPUT CURRENT: IOUT(mA) OUTPUT CURRENT: IOUT(mA) 100 8.0V VIN = 4.0V 0 0.1 1000 100 80 1 10 100 OUTPUT CURRENT: IOUT(mA) 1000 80 VIN = 3.96V 8.0V 10.0V 60 40 20 0 0.1 1 10 100 1000 OUTPUT CURRENT: IOUT(mA) ©2001 Fairchild Semiconductor Corporation 9 ILC6376/77 Typical Performance Characteristics General conditions for all curves: Circuit 1; L = 20µH (Sumida, CD54), CIN = 47µF (tantalum) with 0.1µF (ceramic), CL = 47µH (tantalum) SS12 schottky diode, CSS = 4700pF (ceramic), TA = 25°C unless otherwise noted. Output vs. Ambient Temperature 3.40 ILC6377SO33 100 SUPPLY CURRENT: IIN(µA) OUTPUT VOLTAGE (V) Stand-by Current vs. Ambient Temperature ILC6377SO33 3.35 3.30 3.26 3.20 -40 -20 0 20 40 60 80 60 40 20 0 -40 80 -20 Output Voltage vs. Ambient Temperature 60 80 On Resistance vs. Ambient Temperature ILC6377SO33 ILC6377SO33 SWITCH RESISTANCE: RDS(ON)(Ω) STAND-BY CURRENT (µA) 40 AMBIENT TEMP.: TA (˚C) AMBIENT TEMP.: TA (˚C) 3.40 20 0 3.35 3.30 3.25 3.20 1.2 1.0 0.8 0.6 0.4 0.2 -40 -20 0 20 40 60 -40 80 -20 AMBIENT TEMP.: TA (˚C) 60 80 ILC6377SO33 3.40 PFM DUTY RATIO: PFMDTY(%) OSCILLATION FREQUENCY: FOSC(kHz) ILC6377SO33 350 300 250 200 -40 40 PFM Duty Ration vs. Ambient Temperature Oscillation Frequency vs. Ambient Temperature 400 20 0 AMBIENT TEMP.: TA (˚C) -20 0 20 40 AMBIENT TEMP.: TA (˚C) 60 80 3.35 3.30 3.25 3.20 -40 -20 0 20 40 60 80 AMBIENT TEMP.: TA (˚C) ©2001 Fairchild Semiconductor Corporation 10 ILC6376/77 Typical Performance Characteristics General conditions for all curves: Circuit 1; L = 20µH (Sumida, CD54), CIN = 47µF (tantalum) with 0.1µF (ceramic), CL = 47µH (tantalum) SS12 schottky diode, CSS = 4700pF (ceramic), TA = 25°C unless otherwise noted. Minimum Operating Voltage vs. Ambient Temperature Efficiency vs. Ambient Temperature ILC6377SO33 ILC6377SO33 MIN. OPERATING VOLTAGE: VOUT(V) EFFICIENCY: EFFI(%) 100 90 80 70 60 50 -40 -20 0 20 40 60 1.8 1.6 1.4 1.2 1.0 0.8 80 -40 -20 AMBIENT TEMP.: TA (˚C) 0 20 40 60 80 AMBIENT TEMP.: TA (˚C) Soft-Start Time vs. Ambient Temperature CE "H" Voltage vs. Ambient Temperature ILC6377SO33 ILC6377SO33 16 CE "H" VOLTAGE: VCEL(V) SOFT-START TIME: TSS(ms) 1.0 12 8 4 0 -40 -20 0 20 40 60 80 AMBIENT TEMP.: TA (˚C) 0.8 0.6 0.4 0.2 0 -40 -20 0 20 40 60 80 AMBIENT TEMP.: TA (˚C) CE "L" Voltage vs. Ambient Temperature ILC6377SO33 CE "L" VOLTAGE: VCEL(V) 1.0 0.8 0.6 0.4 0.2 0.8 -40 -20 0 20 40 60 80 AMBIENT TEMP.: TA (˚C) ©2001 Fairchild Semiconductor Corporation 11 ILC6376/77 Ordering Information ILC6376SO33 3.3V, 300kHz step-down PWM converter ILC6376SO50 5V, 300kHz step-down PWM converter ILC6376ADJ Adjustable, 300kHz step-down PWM converter ILC6377SO33 3.3V, 300kHz step-down PWM/PFM converter ILC6377SO50 5V, 300kHz step-down PWM/PFM converter ILC6377SOADJ Adjustable, 300kHz step-down PWM/PFM converter DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 11/21/01 0.0m 001 Stock#DSxxxxxxxx 2001 Fairchild Semiconductor Corporation