LMX2323 PLLatinum™ 2.0 GHz Frequency Synthesizer for RF Personal Communications General Description Features The LMX2323 is a high performance frequency synthesizer with integrated 32/33 dual modulus prescaler designed for RF operation up to 2.0 GHz. Using a proprietary digital phase locked loop technique, the LMX2323’s linear phase detector characteristics can generate very stable, low noise control signals for UHF and VHF voltage controlled oscillators. Serial data is transferred into the LMX2323 via a three-line MICROWIRE™ interface (Data, LE, Clock). Supply voltage range is from 2.7V to 5.5V. The LMX2323 features very low curent consumption, typically 3.5mA at 3V. The charge pump provides 4 mA output current. The LMX2323 is manufactured using National’s ABiC V BiCMOS process and is packaged in a 16-pin TSSOP. n RF operation up to 2.0 GHz n 2.7V to 5.5V operation n Low current consumption: Icc = 3.5mA (typ) at Vcc=3.0V n Digital Lock Detect n Dual modulus prescaler: 32/33 n Internal balanced, low leakage charge pump Applications n Cellular telephone systems (GSM, NADC, CDMA, PDC, PHS) n Personal wireless communications (DCS-1800, DECT, CT-1+) n Wireless local area networks (WLANs) n DCS/PCS infrastructure equipment n Other wireless communication systems Functional Block Diagram DS101362-1 TRI-STATE ® is a registered trademark of National Semiconductor Corporation. MICROWIRE™ and PLLatinum™ are trademarks of National Semiconductor Corporation. © 2000 National Semiconductor Corporation DS101362 www.national.com LMX2323 PLLatinum 2.0 GHz Frequency Synthesizer for RF Personal Communications October 2000 LMX2323 Connection Diagram DS101362-2 Top View Order Number LMX2323TM, LMX2323TMX See NS Package Number MTC16 Pin Descriptions Pin No. Pin Name I/O 1 OSCIN I 3 VP — Power supply for charge pump. Must be ≥ VCC. 4 VCC — Power supply voltage input. Input may range from 2.7V to 5.5V. Bypass capacitors should be placed as close as possible to this pin and be connected directly to the ground plane. 5 CPo O Internal charge pump output. For connection to a loop filter for driving the voltage control input of an external oscillator. 6 GND — 7 fINB I Description Oscillator input. A CMOS inverting gate input. The input has a VCC/2 input threshold and can be driven from an external CMOS or TTL logic gate. Ground. RF prescaler complimentary input. In single-ended mode, a bypass capacitor should be placed as close as possible to this pin and be connected directly to the ground plane. The LMX2323 can be driven differentially when a bypass capacitor is omitted. 8 fIN I RF prescaler input. Small signal input from the voltage controlled oscillator. 9 Clock I High impedance CMOS Clock input. Data is clocked in on the rising edge, into the various counters and registers. 10 Data I Binary serial data input. Data entered MSB first. LSB is control bit. High impedance CMOS input. 11 LE I Load Enable input. When Load Enable transitions HIGH, data is loaded into either the N or R register (control bit dependent). See timing diagram. 12 CE I PLL Enable. A LOW on CE powers down the device asynchronously and TRI-STATE ® s the charge pump output. 14 LD O Lock detect output. This pin can be programmed to provide R counter output, N counter output, digital lock detect (CMOS logic) or analog lock detect (open drain). 2, 13, 15, 16 NC www.national.com No Connect. 2 LMX2323 Absolute Maximum Ratings (Note 1) Recommended Operating Conditions (Note 1) Power Supply Voltage (VCC) −0.3V to 6.5V VCC to 6.5V Power Supply for Charge Pump (VP) Voltage on Any Pin with −0.3V to VCC + 0.5V GND = 0V (VI) −65˚C to +150˚C Storage Temperature Range (TS) +260˚C Lead Temperature (solder, 4 sec.) (TL) ESD - Whole Body Model (Note 2) 2 kV Power Supply Voltage (VCC) Power Supply for Charge pump (VP) Operating Temperature (TA) 2.7V to 5.5V VCC to 5.5V −40˚C to +85˚C Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Conditions indicate conditions for which the device is intended to be functional. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: This device is a high performance RF integrated circuit and is ESD sensitive. Handling and assembly of this device should be done on ESD protected workstations. Electrical Characteristics VCC = 3.0V, VP = 3.0V; −40˚C < TA < 85˚C except as specified. Symbol Parameter Conditions Min Typ Max Units GENERAL ICC Power Supply Current VCC = 3.0V 3.5 ICC VCC = 2.7V to 5.5V ICC-PWDN VCC = 5.5V (Note 3) fIN RF Operating Frequency fOSC Oscillator Frequency fφ Phase Detector Frequency PfIN RF Input Sensitivity VOSC mA 7.0 10 mA 20 µA 0.1 2.0 GHz 5 40 MHz 10 MHz 2.7V≤Vcc≤ 3.0V -15 0 dBm 3.0 < Vcc≤5.0V -10 0 dBm VCC-0.3 VPP (Note 6) dBc/Hz Oscillator Sensitivity 0.4 0.8 fIN = 900 MHz, VOSC ≥ 0.8 VPP −86 fIN = 900 MHz, VOSC ≥ 0.4 VPP −82 fIN = 1800 MHz, VOSC ≥ 0.8 VPP −82 fIN = 1800 MHz, VOSC ≥ 0.4 VPP −80 Charge Pump Output Current VCPo = VP/2 −4.3 mA VCPo = VP/2 4.3 mA ICPo-Tri Charge Pump TRI-STATE Current 0.5 ≤ VCPo ≤ VP - 0.5 ICPo vs VCPo Charge Pump Output Current Magnitude Variation vs Voltage 0.5 ≤ VCPo ≤ VP - 0.5 TA = 25˚C 10 % ICPo-sink vs ICPo-source Charge Pump Output Current Sink vs Source Mismatch VCPo = VP/2 TA = 25˚C 5 % ICPo vs T Charge Pump Output Current Magnitude Variation vs Temperature VCPo = VP/2 8 % Phase Noise (Note 4) CHARGE PUMP ICPo-source ICPo-sink −2.5 2.5 nA DIGITAL INTERFACE (DATA, CLK,LE, CE) VOH High-Level Output Voltage IOH = −500 µA IOL = −500 µA VOL Low-Level Output Voltage VIH High-Level Input Voltage (Note 5) VIL Low-Level Input Voltage (Note 5) IIH High-Level Input Current (Clock, Data, Load Enable) VIH = VCC = 5.5V IIL Low-Level Input Current (Clock, Data, Load Enable) VIL = 0, VCC = 5.5V IIH Oscillator Input Current VIH = VCC = 5.5V IIL Oscillator Input Current VIL = 0, VCC = 5.5V VCC−0.4 V 0.4 0.8Vcc 3 V V 0.2Vcc V −1.0 1.0 µA −1.0 1.0 µA 100 µA −100 µA www.national.com LMX2323 Electrical Characteristics (Continued) VCC = 3.0V, VP = 3.0V; −40˚C < TA < 85˚C except as specified. Symbol Parameter Conditions Min Typ Max Units MICROWIRE TIMING tCS Data to Clock Set Up Time tCH Data to Clock Hold Time See Data Input Timing 10 ns tCWH Clock Pulse Width High See Data Input Timing 50 ns tCWL Clock Pulse Width Low See Data Input Timing 50 ns tES Clock to Enable Set Up Time See Data Input Timing 50 ns tEW Enable Pulse Width See Data Input Timing 50 ns See Data Input Timing 50 ns Note 3: This ICC-PWDN represents CLK, DATA, LE and CE being tied to either higher than 0.8 VCC or lower than 0.2 VCC. Note 4: Phase noise is measured 1 kHz off from the carrier frequency. Comparison frequency is 200 kHz. OSCIN frequency is 13 MHz. Note 5: Except fIN and OSCIN. Note 6: Typical values are determined from measurements on the reference evaluation boards. A 3 dB (3 sigma) degradation is estimated from statistical distribution in manufacturing. Units will NOT be tested in production. Charge Pump Current Specification Definitions DS101362-4 I1 = CP sink current at VCPo = VP − ∆V I2 = CP sink current at VCPo = VP/2 I3 = CP sink current at VCPo = ∆V I4 = CP source current at VCPo = VP − ∆V I5 = CP source current at VCPo = VP/2 I6 = CP source current at VCPo = ∆V ∆V = Voltage offset from positive and negative rails. Dependent on VCO tuning range relative to VCC and ground. Typical values are between 0.5V and 1.0V. 1. ICPo vs VCPo = Charge Pump Output Current magnitude variation vs Voltage = [1⁄2 * {|I1| − |I3|}] / [1⁄2 * {|I1| + |I3|}] * 100% and [1⁄2 * {|I4| − |I6|}] / [1⁄2 * {|I4| + |I6|}] * 100% 2. ICPo-sink vs ICPo-source = Charge Pump Output Current Sink vs Source Mismatch = [|I2| − |I5|] / [1⁄2 * {|I2| + |I5|}] * 100% 3. ICPo vs TA = Charge Pump Output Current magnitude variation vs Temperature = [|I2 @ temp| − |I2 @ 25˚C|] / |I2 @ 25˚C| * 100% and [|I5 @ temp| − |I5 @ 25˚C|] / |I5 @ 25˚C| * 100% www.national.com 4 LMX2323 Typical Performance Characteristics ICCvs VCC Charge Pump Current vs VCPo Output DS101362-13 DS101362-14 RF Input Sensitivity vs Frequency Oscillator Input Sensitivity DS101362-16 DS101362-15 5 www.national.com LMX2323 1.5 CHARGE PUMP 1.0 Functional Description The phase detector’s current source output pumps charge into an external loop filter, which then converts the charge into the VCO’s control voltage. The charge pumps steer the charge pump output, CPo, to VP (pump-up) or Ground (pump-down). When locked, CPo is primarily in a TRI-STATE mode with small corrections. The RF charge pump output current magnitude is set to 4.0 mA. The charge pump output can also be used to output divider signals as detailed in section 2.2.3. The basic phase-lock-loop (PLL) configuration consists of a high-stability crystal reference oscillator, a frequency synthesizer such as the National Semiconductor LMX2323, a voltage controlled oscillator (VCO), and a passive loop filter. The frequency synthesizer includes a phase detector, current mode charge pump, as well as programmable reference [R] and feedback [N] frequency dividers. The VCO frequency is established by dividing the crystal reference signal down via the R counter to obtain a frequency that sets the comparison frequency. This reference signal, fr, is then presented to the input of a phase/frequency detector and compared with another signal, fp, the feedback signal, which was obtained by dividing the VCO frequency down by way of the N counter. The phase/frequency detector’s current source outputs pump charge into the loop filter, which then converts the charge into the VCO’s control voltage. The phase/frequency comparator’s function is to adjust the voltage presented to the VCO until the feedback signal’s frequency (and phase) match that of the reference signal. When this “phase-locked” condition exists, the RF VCO’s frequency will be N times that of the comparison frequency, where N is the divider ratio. 1.6 MICROWIRE SERIAL INTERFACE The programmable functions are accessed through the MICROWIRE serial interface. The interface is made of three functions: clock, data and latch enable (LE). Serial data for the various counters is clocked in from data on the rising edge of clock, into the 18-bit shift register. Data is entered MSB first. The last bit decodes the internal register address. On the rising edge of LE, data stored in the shift register is loaded into one of the two appropriate latches (selected by address bits). A complete programming description is included in the following sections. 1.7 LOCK DETECT OUTPUT A digital filtered lock detect function is included through an internal digital filter to produce a CMOS logic output available on the LD output pin if selected. The lock detect output is high when the error between the phase detector inputs is less than 15 ns for five consecutive comparison cycles. The lock detect output is low when the error between the phase detector input is more than 30 ns for one comparison cycle. An open drain, analog lock detect status generated from the phase detector is also available on the LD output pin, if selected. The analog lock detect output goes high when the charge pump is inactive. It goes low when the charge pump is active during a comparison cycle. When the PLL is in power down mode, the LD output is always high. 1.1 OSCILLATOR The reference oscillator frequency for the PLL is provided by an external reference TCXO through the OSCIN pin. OSCIN block can operate to 40 MHz. The inputs have a VCC/2 input threshold and can be driven from an external CMOS or TTL logic gate. 1.2 REFERENCE DIVIDER (R COUNTER) The R Counter is clocked through the oscillator block. The maximum input frequency is 40 MHz and the maximum output frequency is 10 MHz. The R Counter is a 10-bit CMOS binary counter with a divide range from 2 to 1,023. See programming description 2.2.1. 1.3 PROGRAMMABLE DIVIDER (N COUNTER) The N counter is clocked by the small signal fIN input. The LMX2323 RF N counter is a 15-bit integer divider. The N counter is configured as a 5-bit A Counter and a 10-bit B Counter, offering a continuous integer divide range from 992 to 32,767. The LMX2323 is capable of operating from 100 MHz to 2.0 GHz with a 32/33 prescaler. 1.8 POWER CONTROL The PLL can be power controlled in two ways. The first method is by setting the CE pin LOW. This asynchronously powers down the PLL and TRI-STATEs the charge pump output, regardless of the PWDN bit status. The second method is by programming through MICROWIRE, while keeping the CE HIGH. Programming the PWDN bit in the N register HIGH (CE = HIGH) will disable the N counter and de-bias the fIN input (to a high impedance state). The R counter functionality also becomes disabled. The reference oscillator block powers down when the power down bit is asserted. The OSCIN pin reverts to a high impedance state when this condition exists. Power down forces the charge pump and phase comparator logic to a TRI-STATE condition. A power down counter reset function resets both N and R counters. Upon powering up the N counter resumes counting in “close” alignment with the R counter (the maximum error is one prescaler cycle). The MICROWIRE control register remains active and capable of loading and latching in data during all of the power down modes. 1.3.1 Prescaler The RF inputs to the prescaler consist of the fIN and fINB pins which are the complimentary inputs of a differential pair amplifier. The differential fIN configuration can operate to 2 GHz. The input buffer drives the N counter’s ECL D-type flip-flops in a dual modulus configuration. The LMX2323 has a 32/33 prescaler ratio. The prescaler clocks the subsequent CMOS flip-flop chain comprising the fully programmable A and B counters. 1.4 PHASE/FREQUENCY DETECTOR The phase/frequency detector is driven from the N and R counter outputs. The maximum frequency at the phase detector inputs is 10 MHz. The phase detector outputs control the charge pumps. The polarity of the pump-up or pumpdown control is programmed using PD_POL, depending on whether RF VCO characteristics are positive or negative (see programming description 2.2.2). The phase detector also receives a feedback signal from the charge pump, in order to eliminate dead zone. www.national.com 6 LMX2323 2.0 Programming Description 2.1 MICROWIRE INTERFACE The MICROWIRE interface is comprised of an 18-bit shift register, a R register and a N register. The shift register consists of a 17-bit DATA field and a 1-bit address (ADDR) field as shown below. When Latch Enable transitions HIGH, data stored in the shift register is loaded into either the R or N register depending on the ADDR bit as described in Table 2.1.1. The data is loaded MSB first. The DATA field assignment for the R and N registers are shown in Table 2.1.2 below. MSB LSB DATA [16:0] ADDR 17 1 0 2.1.1 Address Bit Truth Table When LE is transitioned high, data is transferred from the 18-bit shift register into either the 14-bit R register, or the 17-bit N register depending upon the state of the ADDR bit. ADDR DATA Location 0 N register 1 R register 2.1.2 Register Content Truth Table MSB 17 SHIFT REGISTER BIT LOCATION 16 15 14 13 N Register R Register 12 11 10 9 8 7 LSB 6 NB_CNTR X X LD_OUT 5 4 3 2 NA_CNTR PD_POL CP_TRI 1 0 CTL_WORD 0 R_CNTR 1 2.2 R REGISTER If the Address Bit (ADDR) is 1, when LE is transitioned high data is transferred from the 18-bit shift register into the 14-bit R register. The R register contains a latch which sets the PLL 10-bit R counter divide ratio. The divide ratio is programmed using the bits R_CNTR as shown in 2.2.1 10-Bit Programmable Reference Divider Ratio (R Counter). The ratio must be ≥ 2. The PD_POL and CP_TRI bits control the phase detector polarity and charge pump TRI-STATE respectively, as shown in 2.2.2 R[11], R[12] Truth Table. X denotes a don’t care condition. First Bit SHIFT REGISTER BIT LOCATION 17 16 X X 15 14 13 LD_OUT 12 11 PD_POL CP_TRI 10 9 8 Last Bit 7 6 5 4 3 2 1 0 R_CNTR [9:0] 1 2.2.1 10-Bit Programmable Reference Divider Ratio (R Counter) R_CNTR Divide Ratio 9 8 7 6 5 4 3 2 1 0 2 0 0 0 0 0 0 0 0 1 0 3 0 0 0 0 0 0 0 0 1 1 • 1,023 • 1 • 1 • 1 • 1 • 1 • 1 • 1 • 1 • 1 • 1 Note: Divide ratio: 2 to 1,023 (Divide ratios less than 2 are prohibited). R_CNTR — These bits select the divide ratio of the programmable reference dividers. 2.2.2 R[11], R[12] Truth Table Bit Location Function 0 1 CP_TRI R[11] Charge Pump TRI-STATE Normal Operation TRI-STATE PD_POL R[12] Phase Detector Polarity Negative Positive Note: Depending upon VCO characteristics, R[12] shoud be set accordingly. When VCO characteristics are positive, R[12] should be set HIGH. When VCO characteristics are negative, R[12] should be set LOW. 7 www.national.com LMX2323 2.0 Programming Description (Continued) 2.2.3 LD_OUT Truth Table (R[13]-[15]) R[15] R[14] R[13] Digital Lock Detect LD Pin Output 0 0 0 Analog Lock Detect 0 0 1 R Divider Output 0 1 0 N Divider Output 0 1 1 Test Mode 1 0 0 Note: Do not use Test mode in normal operation. Test mode is for factory testing purpose only. It allows direct testing of the digital lock detect by using the CLK and Data as the R and N counter outputs. The Lock Detect Digital Filter compares the phase difference of the inputs from the phase detector to a RC generated delay of approximately 15 ns. To enter the locked state (LD = High), the phase error must be less than the 15 ns RC delay for 5 consecutive reference cycles. Once in lock, the RC delay is changed to approximately 30 ns. To exit the locked state, the phase error must be greater than the 30 ns RC delay. When the PLL is in power down mode, LD is forced to High state. A flow chart of the digital filter is shown as below: www.national.com 8 LMX2323 2.0 Programming Description (Continued) DS101362-5 2.3 N REGISTER If the address bit is LOW (ADDR = 0), when LE is transitioned high, data is transferred from the 18-bit shift register into the 17-bit N register. The N register consists of the 5-bit swallow counter (A counter), the 10-bit programmable counter (B counter) and the control word. Serial data format is shown below in 2.3.1 5-Bit Swallow Counter Divide Ratio (A Counter) and 2.3.2 10-Bit Programmable Counter Divide Ratio (B Counter). The pulse swallow function which determines the divide ratio is described in section 2.3.3 Pulse Swallow Function. First Bit 17 16 SHIFT REGISTER BIT LOCATION 15 14 13 12 11 10 9 8 7 NB_CNTR [9:0] Last Bit 6 5 NA_CNTR [4:0] 9 4 3 2 1 CTL_WORD [1:0] 0 0 www.national.com LMX2323 2.0 Programming Description (Continued) 2.3.1 5-Bit Swallow Counter Divide Ratio (A Counter) Swallow Count NA_CNTR (A) 4 3 2 1 0 0 0 0 0 0 0 1 0 0 0 0 1 • 31 • 1 • 1 • 1 • 1 1 • Notes: Swallow Counter Value: 0 to 31 NB_CNTR ≥ NA_CNTR 2.3.2 10-Bit Programmable Counter Divide Ratio (B Counter) NB_CNTR Divide Ratio 9 8 7 6 5 4 3 2 1 0 3 0 0 0 0 0 0 0 0 1 1 4 0 0 0 0 0 0 0 1 0 0 • 1023 • 1 • 1 • 1 • 1 • 1 • 1 • 1 • 1 • 1 • 1 Notes: Divide ratio: 3 to 1,023 (Divide ratios less than 3 are prohibited). NB_CNTR ≥ NA_CNTR 2.3.3 Pulse Swallow Function The N divider counts such that it divides the VCO RF frequency by (P+1) A times, and then divides by P (B - A) times. The B value (NB_CNTR) must be ≥ 3. The continuous divider ratio is from 992 to 32,767. Divider ratios less than 992 are achievable as long as the binary counter value is greater than the swallow counter value (NB_CNTR ≥ NA_CNTR). fVCO = N x (fOSC/R) N = (P x B) + A fVCO: Output frequency of external voltage controlled oscillator (VCO) fOSC: Output frequency of the external reference frequency oscillator R: Preset divide ratio of binary 10-bit programmable reference counter (2 to 1023) N: Preset divide ratio of main 15-bit programmable integer N counter (992 to 32,767) B: Preset divide ratio of binary 10-bit programmable B counter (3 to 1023) A: Preset value of binary 5-bit swallow A counter (0 ≤ A ≤ 31, A ≤ B) P: Preset modulus of dual modulus prescaler (P = 32) 2.3.4 CTL_WORD MSB LSB N2 N1 CNT_RST PWDN 2.3.4.1 Reserve Word Truth Table CE CNT_RST PWDN 1 0 0 Normal Operation Function 1 0 1 Synchronous Powerdown 1 1 0 Counter Reset 1 1 1 Asynchronous Powerdown 0 X X Asynchronous Powerdown Notes: X denotes don’t care. 1. The Counter Reset bit when activated allows the reset of both N and R counters. Upon powering up the N counter resumes counting in “close” alignment with the R counter. (The maximum error is one prescaler cycle). www.national.com 10 2. (Continued) Both synchronous and asynchronous power down modes are available with the LMX2323 to be able to adapt to different types of applications. The MICROWIRE control register remains active and capable of loading and latching in data during all of the powerdown modes. Synchronous Power down Mode The PLL loops can be synchronously powered down by setting the counter reset mode bit to LOW (N[2] = 0) and its power down mode bit to HIGH (N[1] = 1). The power down function is gated by the charge pump. Once the power down mode and counter reset mode bits are loaded, the part will go into power down mode upon the completion of a charge pump pulse event. Asynchronous Power down Mode The PLL loops can be asynchronously powered down by setting the counter reset mode bit to HIGH (N[2] = 1) and its power down mode bit to HIGH (N[1] = 1). The power down function is NOT gated by the charge pump. Once the power down and counter reset mode bits are loaded, the part will go into power down mode immediately. The R and N counters are disabled and held at load point during the synchronous and asynchronous power down modes. This will allow a smooth acquisition of the RF signal when the PLL is programmed to power up. Upon powering up, both R and N counters will start at the ‘zero’ state, and the relationship between R and N will not be random. Serial Data Input Timing DS101362-6 Notes: Parenthesis data indicates programmable reference divider data. Data shifted into register on clock rising edge. Data is shifted in MSB first. Test Conditions: The Serial Data Input Timing is tested using a symmetrical waveform around VCC/2. The test waveform has an edge rate of 0.6 V/ns with amplitudes of 2.2V @ VCC = 2.7V and 2.6V @ VCC = 5.5V. Phase Comparator and Internal Charge Pump Characteristics DS101362-7 Notes: Phase difference detection range: −2π to +2π The minimum width pump up and pump down current pulses occur at the CPo pin when the loop is locked. PD_POL = 1 fr: Phase comparator input from the R divider fp: Phase comparator input from the N divider CPo: Charge pump output 11 www.national.com LMX2323 2.0 Programming Description LMX2323 PLLatinum 2.0 GHz Frequency Synthesizer for RF Personal Communications Physical Dimensions inches (millimeters) unless otherwise noted 16-Pin Thin Shrink Small Outline Package Order Number LMX2323TM, LMX2323TMX NS Package Number MTC16 LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL 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 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 to the user. National Semiconductor Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: [email protected] www.national.com National Semiconductor Europe Fax: +49 (0) 180-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 2. A critical component is 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. 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