www.fairchildsemi.com KH600 1GHz, Differential Input/Output Amplifier Features ■ ■ ■ ■ ■ ■ ■ ■ General Description The KH600 is the first amplifier to combine differential input and output with a bandwidth of DC-1GHz at 2Vpp. The inputs and outputs are 100Ω differential (50Ω single ended). The KH600 operates from ±5V supplies and offers a fixed gain of 14dB (5V/V). DC - 1GHz bandwidth Fixed 14dB (5V/V) gain 100Ω (differential) inputs and outputs -74/-64dBc 2nd/3rd HD at 50MHz 45mA output current 9Vpp into 100Ω differential load 13,000V/µs slew rate Optional supply current and offset voltage adjustment The KH600 also offers optional supply current, differential output offset voltage, and common mode offset voltage adjustments. The KH600 is constructed using Fairchild's in-house thin film resistor/bipolar transistor technology. The KH600 is available in a 12-pin TO8 package. Applications ■ ■ ■ ■ ■ ATE systems High-end instrumentation High bandwidth output amplifier Differential buffer Line driver Typical Application Single Tone Intercept Point 100 90 50Ω 50Ω Distortion (dBm) + Differential 100Ω Source The KH600 includes 50Ω resistors from each input to ground (resulting in a differential input impedance of 100Ω). 80 I2 70 60 50 40 I3 30 20 0 50 100 150 200 250 300 350 Frequency (MHz) 5Vpp Pulse Response 2nd and 3rd Harmonic Distortion 3 -30 Vo = 2Vpp 2 Output voltage (V) Distortion (dBc) -40 -50 -60 3rd -70 2nd -80 1 0 -1 -2 -90 -3 -100 0 50 100 150 200 250 300 Time (2ns/div) Frequency (MHz) REV. 1A February 2001 DATA SHEET KH600 KH600 Electrical Characteristics Parameters (G = +5V/V (14dB), RL = 100Ω (differential), Ta = +25°C, +Vb1 = +Vb2 = +Vs = +5V, -Vb = -Vs = -5V; unless noted) Conditions Case Temperature Frequency Domain Response -3dB bandwidth peaking Vo = 2Vpp DC to 250MHz DC to 500MHz full power bandwidth Vo = 8Vpp linear phase deviation DC to 500MHz gain 1MHz DC input return loss (single-ended 50Ω) DC = 250MHz DC = 500MHz output return loss (single-ended 50Ω) DC = 500MHz Time Domain Response rise and fall time overload recovery slew rate Distortion and Noise Response 2nd harmonic distortion 3rd harmonic distortion input referred noise noise figure DC Performance output offset voltage average drift power supply rejection ratio (±Vs) supply current Output Characteristics output voltage swing output current Recommended Operating Conditions total supply voltage -Vb +Vb1, +Vb2 input voltage (relative to gain) TYP Min & Max +25°C +25°C 1000 0.2 0.5 350 3 14 14.3 22 14 27 2V step 8V step Vin = 4Vpp 8V step MHz dB dB MHz deg dB dB dB dB dB ±0.1 350 1 900 13,000 5Vpp, 50MHz 2Vpp, 50MHz 1Vpp, 200MHz 5Vpp, 50MHz 2Vpp, 50MHz 1Vpp, 200MHz >1MHz 61 74 65 46 64 70 1.35 6.5 I/O’s terminated into 50Ω to GND -18 200 55 67 22 DC ±Vs pins ±Vb pins (+Vb1 shorted to +Vb2) UNITS NOTES 1 ps ns ps V/µs dBc dBc dBc dBc dBc dBc nV/√Hz dB 61 57 ±60 mV µV/°C dB mA mA 70 24 differential 9 ±45 Vpp mA (+Vs to -Vs) 4 to 12 0 to -12 0 to 12 ±2 V V V V 1 1 1 1 1 Min/max ratings are based on product characterization and simulation. Individual parameters are tested as noted. Outgoing quality levels are determined from tested parameters. NOTES: 1) 100% tested at 25°C. Absolute Maximum Ratings total supply voltage maximum junction temperature storage temperature range lead temperature (10 sec) KH600 Package 15V +150°C -65°C to +150°C +300°C 12-pin TO8 TOP VIEW GND +Vb1 +Vs 12 11 10 +In -Vb +OUT 1 9 2 8 3 7 -In -Vs -OUT 4 5 6 GND +Vb2 +Vs NOTE: Case is grounded. 2 REV. 1A February 2001 KH600 DATA SHEET KH600 Performance Characteristics (G = +5V/V (14dB), RL = 100Ω (differential), Ta = +25°C, +Vb1 = +Vb2 = +Vs = +5V, -Vb = -Vs = -5V; unless noted) Small Signal AC Response (S21) Input and Output Return Loss (S11/S22) 0 Magnitude (dB) Magnitude (1dB/div) -6 -12 -18 -24 -30 S11 Ch1 -36 -42 -48 -54 S22 Ch2 -60 -66 1 10 100 1000 1 10 Frequency (MHz) Reverse Isolation (S12) Linear Phase Deviation (deg) 5 Magnitude (dB) -16 -22 -28 -34 -40 -46 -52 -58 4 3 2 1 0 -1 1 10 100 1000 1 100 200 Frequency (MHz) 300 400 500 Frequency (MHz) Input Noise Differential Gain vs. Supply Voltage 1.5 6 ±Vb = ±Vs Differential Gain (V/V) Input Refered Noise (nV√Hz) 1000 Linear Phase Deviation -10 1.4 1.3 1.2 1.1 1.0 5 4 3 2 1 0 1 10 100 1000 1 2 Frequency (MHz) 5 6 7 20 Vo = 1Vpp Vo = 1Vpp 0 -20 -20 IMD (dBc) 0 -40 -60 -40 -60 -80 -80 49.65 49.85 50.05 Frequency (MHz) REV. 1A February 2001 4 2 Tone 3rd Order Intermod. Distortion 2 Tone 3rd Order Intermod. Distortion -100 49.45 3 Supply Voltage (±V) 20 IMD (dBc) 100 Frequency (MHz) 50.25 50.45 -100 99.45 99.65 99.85 100.05 100.25 100.45 Frequency (MHz) 3 DATA SHEET KH600 KH600 Performance Characteristics (G = +5V/V (14dB), RL = 100Ω (differential), Ta = +25°C, +Vb1 = +Vb2 = +Vs = +5V, -Vb = -Vs = -5V; unless noted) 2 Tone 3rd Order Intermod. Distortion 2 Tone 3rd Order Intermod. Distortion 20 20 Vo = 5Vpp 0 -20 -20 IMD (dBc) IMD (dBc) Vo = 5Vpp 0 -40 -60 -80 -40 -60 -80 -100 49.45 49.65 49.85 50.05 50.25 50.45 -100 99.45 99.65 Frequency (MHz) 99.85 100.05 2nd Harmonic Distortion vs. Vo -30 -40 -40 Vo = 5Vpp -50 Distortion (dBc) Distortion (dBc) Vo = 5Vpp Vo = 2Vpp -60 -70 Vo = 0.5Vpp -80 -50 Vo = 2Vpp -60 Vo = 1Vpp -70 -80 Vo = 0.5Vpp Vo = 1Vpp -90 -90 -100 -100 0 50 100 150 200 250 300 0 50 Frequency (MHz) 90 23 Power Output (dBm) Distortion (dBm) 24 I2 70 60 50 40 I3 30 150 200 250 300 -1dB Compression 100 80 100 Frequency (MHz) Single Tone Intercept Point 22 21 20 19 18 17 16 20 0 50 100 150 200 250 300 0 350 100 70 23 Supply Current (mA) 24 68 +Vs -Vs 64 300 400 500 Vb Supply Currents vs. Temperature Vs Supply Currents vs. Temperature 72 66 200 Frequency (MHz) Frequency (MHz) Supply Current (mA) 100.45 3rd Harmonic Distortion vs. Vo -30 62 60 22 -Vb 21 +Vb1 shorted to +Vb2 20 19 18 58 -40 -20 0 20 40 Temperature (°C) 4 100.25 Frequency (MHz) 60 80 -40 -20 0 20 40 60 80 Temperature (°C) REV. 1A February 2001 KH600 DATA SHEET KH600 Performance Characteristics (G = +5V/V (14dB), RL = 100Ω (differential), Ta = +25°C, +Vb1 = +Vb2 = +Vs = +5V, -Vb = -Vs = -5V; unless noted) Output Offset vs. Temperature Differential Output Offset vs. Temperature 0 4 3 2 -20 Output (mV) Output (mV) -10 OUT1 OUT2 -30 1 0 -1 -2 -40 Inputs/outputs terminated into 50Ω to GND --3 -50 -4 -40 -20 0 20 40 60 80 -40 Temperature (°C) -20 0 20 40 60 80 Temperature (°C) Clipping Response Low Frequency Gain vs. Temperature 8 14.2 6 4 Output (V) Gain (dB) 14.1 14 2 0 -2 -4 13.9 -6 -8 13.8 0 20 40 60 80 Time (2ns/div) Temperature (°C) REV. 1A February 2001 5 DATA SHEET KH600 +Vs Pin Description +Vb2 Positive bias voltage for OUT2 -Vb Negative bias voltage for OUT1 and OUT2 1 IN1 Input 1, +IN 3 IN2 Input 2, -IN 9 OUT1 Output 1, +OUT 7 OUT2 Output 2, -OUT 4, 12 GND Input termination ground and case 1 2 -Vs 9 U1 KH600 -Vb -Vs 3 8 7 C6 0.01µF 4 2 -Vs 10 5 11 Positive bias voltage for OUT1 +Vs +Vb1 +Vs +Vs GND -Vs -Vs C8 0.01µF +Vs 11 6 Negative supply voltage 12 Positive supply voltage -Vs GND +Vs 8 +OUT +Vb1 6, 10 C1 0.01µF +IN +Vb2 Function GND Name 5 Pin #’s C9 6.8µF C4 0.01µF C10 6.8µF -OUT -IN +Vs Figure 1: Basic Circuit Configuration General Description Standard Operation: +Vb1 = +Vb2 = +Vs = +5V; -Vb = -Vs = -5V C16 6.8µF The KH600 is a 1GHz differential input/output amplifier constructed using Fairchild’s in-house thin film resistor/ bipolar transistor technology. A differential signal on the inputs of the KH600 will generate a differential signal at the outputs. If a single ended input signal is applied to IN1 and a fixed voltage to IN2, the KH600 will produce both a differential and common-mode output signal. To achieve the maximum dynamic range, center the inputs halfway between +Vs and -Vs. C15 0.01µF The KH600 includes 50Ω resistors from each input to ground, resulting in a differential input impedance of 100Ω. Each KH600 output has a 50Ω resistance, synthesized by feedback, providing a 100Ω differential output impedance. +Vb1 + +Vs C1 0.01µF +OUT 11 10 +Vs GND +Vb1 12 +IN 2 U1 KH600 -Vb -Vs +Vs C13 0.01µF -IN C8 0.01µF 6 GND +Vb2 5 C5 0.01µF 4 + 8 7 3 C6 6.8µF -Vs 9 1 -Vb -OUT C4 0.01µF C14 6.8µF +Vs + +Vb2 The KH600 has 3 bias voltage pins that can be used to: ■ Adjust the supply current ■ Trim the differential output offset voltage ■ Adjust the common mode output offset voltage over a ±3V range If these adjustments are not required, short +Vb1 and +Vb2 to +Vs and -Vb to -Vs as shown in Figure 1. Throughout this data sheet, this configuration (+Vb1 = +Vb2 = +Vs = +5V and -Vb = -Vs = -5V) is referred to as the Standard Operating Condition. All of the plots in the Typical Performance section and the specifications in the Electrical Characteristics table utilize the basic circuit configuration shown in Figure 1, unless otherwise indicated. Figure 2 illustrates the optional circuit configuration, utilizing the bias voltage pins. Further discussions regarding these optional adjustments are provided later in this document. 6 +Vs C9 6.8µF +Vs GND GND -Vs -Vs C10 6.8µF Figure 2: Optional Circuit Configuration (including optional supply current and offset adjust) Gain Differential Gain for the KH600 is defined as (OUT1– OUT2)/(IN1–IN2). Applying identical (same phase) signals to both inputs and measuring one output will provide the Common Mode Gain. Figure 3 shows the differential and common mode gains of the KH600. Figure 4 illustrates the response of the KH600 outputs when one input is driven and the other is terminated into 50Ω. REV. 1A February 2001 KH600 DATA SHEET 15 Gain (dB) Differential Gain 10 5 0 Common Mode Gain -5 -10 40 -40 35 -35 -30 30 -Vb 25 -25 20 -20 15 -15 +Vb1 , +Vb2 10 -10 5 -5 0 1M 10M 100M 1G 0 0 -2 -4 Frequency (Hz) 12 -8 Figure 6: Vb Supply Currents vs -Vb Power Dissipation The KH600 runs at “constant” power, which may be calculated by (Total Is)(Vs – (-Vs)). Under standard operating conditions, the power is 890mW. The power dissipated in the package is completely constant, independent of signal level. In other words, the KH600 runs class A. OUT1 8 OUT2 4 2 0 1M 10M 100M 1G Frequency (Hz) Figure 4: Gain with Single-Ended Input Applied to IN1 Supply Current The KH600 draws supply current from the 2 Vs pins as well as the 3 Vb pins. Under Standard Conditions, the total supply current is typically 89mA. Changing the voltages on the bias voltage pins will change their respective supply currents as shown in Figures 5 and 6. Power Supply Rejection Ratio (PSRR) The KH600 has 5 supply pins, +Vs, -Vs, +Vb1, +Vb2, and -Vb. All of these sources must be considered when measuring the PSRR. Figure 7 shows the response of +Vs and -Vs, looking at OUT2. +Vs and -Vs have the same effect on OUT1. -20 ±Vb = ±5V -40 -60 dB 10 Gain (dB) -6 -Vb (V) Figure 3: Differential and Common Mode Gain 6 -Vb Supply Currents (mA) +Vb Supply Currents (mA) 20 +Vs -80 -Vs -100 -25 -120 -Vb 20 -20 15 -15 +Vb2 10 -10 +Vb1 5 -5 0 0 -5 -Vb Supply Currents (mA) +Vb Supply Currents (mA) 25 5 0 2 4 6 8 +Vb1 (V) Figure 5: Vb Supply Currents vs +Vb1 Changing the voltage on the +Vb1 pin will alter the supply current for +Vb1 only, +Vb2 and -Vb stay constant at typically 11mA and 22mA respectively. See Figure 5. The same principle applies for +Vb2. And Figure 6 illustrates the effect of changing -Vb. REV. 1A February 2001 -140 100k 1M 10M 100M 1G Frequency (Hz) Figure 7: ±Vs PSRR Figure 8 shows the response of OUT1 and OUT2 when +Vb1 changes. The PSRR of the Vb pins is “bad”, which means that they have a large effect on the response of the KH600 when their voltages are changed. This is the desired effect of the bias voltage pins. As Figure 8 indicates, changing +Vb1 has a greater effect on OUT1 than it does on OUT2. Changing +Vb1 has a direct effect on OUT1. Changing +Vb2 has a direct effect on OUT2. See the Trimming Differential Output Offset Voltage section for more details. 7 DATA SHEET KH600 160 0 Total supply Current (mA) -20 ±Vs = ±5V -40 OUT1 dB -60 -80 OUT2 -100 -120 ±Vs = ±5V 140 120 100 80 60 40 20 0 -140 100k 1M 10M 100M 0 1G 2 4 6 8 Vb (V) Frequency (Hz) Figure 8: +Vb PSRR Figure 9: Total Supply Current vs. Vb Single-to-Differential Operation The KH600 is specifically designed for differential-todifferential operation. However, the KH600 can be used in a single-to-differential configuration with some performance degradation. The unused input should be terminated into 50Ω. When driven single-ended, there will be a slight imbalance in the differential output voltages, see Figure 4. This imbalance is approximately 2.88dB. To compensate for this imbalance, attenuate the higher gain output. (If the signal is applied to IN1, attenuate OUT1.) Supply current is relatively independent of the voltages on +Vs and -Vs as shown in Figure 10. Total supply Current (mA) 100 Unused Inputs and/or Outputs For optimal performance, terminate any unused inputs and/or outputs with 50Ω. 80 70 60 50 40 30 20 ±Vb = ±5V 10 0 0 8 4 6 8 Figure 10: Total Supply Current vs. Vs 1100 1000 900 800 700 600 500 40 To adjust the supply current, apply voltages of equal magnitude, but opposite polarity, to the bias voltage pins. For example, setting +Vb1, +Vb2 to +5VDC and -Vb to -5VDC (as shown in Figure 2) results in the standard supply current condition. Setting +Vb1, +Vb2 to +5.5V and -Vb to -5.5V results in an approximate 10% increase in supply current. Figure 9 shows the how the total supply current of the KH600 is effected by changes in the bias voltages (Vb = +Vb1 = +Vb2 = |-Vb|). 2 Supply Voltage (±V) -3dB Bandwidth (MHz) Adjusting Supply Current The KH600 operates class A, so maximum output current is directly proportional to supply current. Adjusting the voltages on +Vb1 and +Vb2 in opposition to -Vb controls supply current. The default supply current of the KH600 has been optimized for best bandwidth and distortion performance. The main reason for adjusting supply current is to either reduce power or increase maximum output current. Adjusting the supply current will not significantly improve bandwidth or distortion and may actually degrade them. 90 60 80 100 120 140 Total Supply Current (mA) Figure 11: -3dB Bandwidth vs. Is REV. 1A February 2001 KH600 DATA SHEET -40 800 2Vpp @ 50MHz 600 3rd 400 -60 Output (mV) Distortion (dB) -50 -70 -80 OUT2 200 0 OUT1 -200 2nd -90 -400 -100 -600 40 60 80 100 120 140 0 2 Total Supply Current (mA) 4 6 8 +Vb2 (V) Figure 12: Harmonic Distortion vs. Total Is Figure 15: Output vs. +Vb2 -10 800 5Vpp @ 50MHz -20 600 3rd -40 400 Output (mV) Distortion (dB) -30 -50 -60 -70 2nd 200 OUT1, OUT2 0 -80 -200 -90 -400 -100 40 60 80 100 120 140 -600 -8 Total Supply Current (mA) -4 -2 0 -Vb (V) Figure 13: Harmonic Distortion vs. Total Is Figure 16: Output vs. -Vb Adjusting Common Mode Output Offset Voltage Short +Vb1 to +Vb2 and vary +Vb and -Vb to adjust common mode output offset voltage. The recommended values for achieving a given output offset are shown in Figure 17. These values were chosen to give the best distortion performance. The exact values are not crucial. 6 4 800 +Vb1, +Vb2 2 +Vs = +7.5V -Vs = -3.5V 0 Volts (V) Trimming Differential Output Offset Voltage Vary +Vb1 and +Vb2 to adjust differential offset voltage. +Vb1 controls OUT1 and +Vb2 controls OUT2. The output voltage moves in a direction opposite to the direction of the bias voltage. Figure 14 shows the resulting voltage change at OUT1 and OUT2 when the voltage on +Vb1 is changed. Figure 15 shows the resulting voltage change at OUT1 and OUT2 when the voltage on +Vb2 is changed. OUT1 and OUT2 change at the same rate when -Vb is changed, as shown in Figure 16. Therefore, changing the voltage on -Vb has no effect on differential output offset voltage. Output (mV) -6 -2 -4 600 -6 400 -8 -Vb -10 OUT1 200 -12 0 0 OUT2 1 2 3 4 Common Mode Voltage (V) -200 Figure 17: Vb vs. Common Mode Voltage -400 -600 0 2 4 6 8 +Vb1 (V) Figure 14: Output vs. +Vb1 REV. 1A February 2001 9 DATA SHEET KH600 For common mode voltages of 0 to -3.5V swap the Vb’s and change the polarity. See the example below. Desired Common Mode Voltage +Vb1 and +Vb2 (V) -Vb (V) 2 Volts 2 -8 -2 Volts 8 -2 Harmonic Distortion (dBc) -40 +Vs = +7.5V -Vs = -3.5V 2Vpp, 50MHz -45 HD2 Layout Considerations General layout and supply bypassing play major roles in high frequency performance. Fairchild has evaluation boards to use as a guide for high frequency layout and as aid in device testing and characterization. Follow the steps below as a basis for high frequency layout: -50 HD3 -55 -60 HD3 -65 -70 HD2 -75 -80 0 1 2 3 Pay close attention to your peak-to-peak output voltage requirement. As you change the common mode voltage, you may need to increase or shift ±Vs in order to achieve your output requirements. A 2V margin is recommended. For example, if your output requirement is 5Vpp and you will be changing the common mode from 1V to 3V set Vs = +7.5 and -Vs to -3.5V. This example calls for a supply voltage of greater than 10V. This will not effect supply current because as Figure 10 indicates, changing ±Vs has no effect on supply current. 4 ■ Include all recommended 6.8µF and 0.01µF bypass capacitors ■ Place the 6.8µF capacitors within 0.75 inches of the power pin ■ Place the 0.01µF capacitors within 0.1 inches of the power pin ■ Remove the ground plane under and around the part, especially near the input and output pins to reduce parasitic capacitance ■ Minimize all trace lengths to reduce series inductances ■ A 10pF to 50pF bypass capacitor can be used between pins 5 and 6 and between pins 10 and 11 to reduce crosstalk from the positive supply Common Mode Output Voltage (V) Figure 18: 2Vpp HD vs. Common Mode Voltage Harmonic Distortion (dBc) -30 +Vs = +7.5V -Vs = -3.5V 5Vpp, 50MHz -35 -40 HD3 HD2 -45 -50 -55 -60 -65 -70 -75 -80 0 1 2 3 4 Common Mode Output Voltage (V) Figure 19: 5Vpp HD vs. Common Mode Voltage g 140 Refer to the evaluation board layouts shown in Figure 21 for more information. Evaluation Board Information The following evaluation boards are available to aid in the testing and layout of this device: Supply Current (mA) +Vs = +7.5V -Vs = -3.5V Evaluation Board 120 100 Is, -Is 80 Description Products KEB007 Basic KH600 Eval Bd KH600 KEB009 KH600 Eval Bd with offset and Icc Adjust Option KH600 60 40 0 1 2 3 4 Common Mode Output Voltage (V) Figure 20: Resulting Is and -Is Do not include capacitors C2, C3, C7, C11, and C12 that are shown on the KEB007 evaluation board. Evaluation board schematics and layouts are shown in Figure 21. Refer to the schematic shown in Figure 1 for the KEB007 board and Figure 2 for the KEB009 board. Figures 18 and 19 illustrate how the common mode voltage effects harmonic distortion. Figure 20 show the resulting Is and -Is supply currents. 10 REV. 1A February 2001 KH600 DATA SHEET KH600 Evaluation Board Layout Figure 21a: KEB007 (top side) Figure 21b: KEB007 (bottom side) Figure 21c: KEB009 (top side) Figure 21d: KEB009 (bottom side) REV. 1A February 2001 11 DATA SHEET KH600 KH600 Package Dimensions L A e1 e2 7 φD e D1 8 9 6 10 5 11 4 12 k φb 3 2 1 α F k1 TO-8 SYMBOL INCHES Minimun Maximum MILIMETERS Minimum Maximum A 0.142 0.181 3.61 4.60 φb 0.016 0.019 0.41 0.48 φD 0.595 0.605 15.11 15.37 φD1 0.543 0.555 13.79 14.10 e 0.400 BSC 10.16 BSC e1 0.200 BSC 5.08 BSC e2 0.100 BSC 2.54 BSC F 0.016 0.030 0.41 0.76 k 0.026 0.036 0.66 0.91 k1 0.026 0.036 0.66 0.91 L 0.310 0.340 7.87 8.64 α 45° BSC NOTES: Seal: cap weld Lead finish: gold per MIL-M-38510 Package composition: Package: metal Lid: Type A per MIL-M-38510 45° BSC Ordering Information Part No. KH600AI Temperature -40°C to +85°C Package 12-pin TO8 Eval. Board KEB007, KEB009 DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICES 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. www.fairchildsemi.com 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. © 2001 Fairchild Semiconductor Corporation