® SP8537 Micropower Sampling 10-Bit A/D Converter ■ ■ ■ ■ ■ ■ ■ ■ Low Cost 10-Bit Serial Sampling ADC 8-Pin NSOIC Plastic Package Low Power @ 250µA including Automatic Shutdown: 1nA(typ) Programmable Input Configuration: Full differential or 2 channel single-ended Single Supply 3.0V to 5.5V operation Half Duplex Digital Serial Interface Sample Rate: 33.9µS DESCRIPTION The SP8537 is a very low power 10-Bit data acquisition chip. TheSP8537 typically draws 250µA of supply current when sampling at 29.5 kHz. Supply current drops linearly as the sample rate is reduced. The ADC automatically powers down when not performing conversions, drawing only leakage current. The SP8537 is available in 8-Pin NSOIC packages, specified over Commercial, Industrial and Extended temperature ranges. The SP8537 is best suited for Battery-Operated Systems, Portable Data Acquisition Instrumentation, Battery Monitoring, and Remote Sensing applications. The serial port allows efficient data transfer to a wide range of microprocessors and microcontrollers over 3 or 4 wires. VCC GND REFL REFH Internal VCC 10 REFL DAC REFH Csample P CH0 COMPARATOR MUX SAR PARALLEL TO SERIAL SHIFT REGISTER Dout CH1 Csample N DIN INPUT DATA REG CS TIMING & CONTROL LOGIC CLK SP8537 Block Diagram SP8537DS/03 SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 1 © Copyright 2000 Sipex Corporation ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. (TA=+25˚C unless otherwise noted) ..................................................... VCC to GND ................................................................................. 7.0V Vin to GND .............................................................. -0.3 to VCC +0.3V Digital input to GND ................................................ -0.3 to VCC +0.3V Digital output to GND .............................................. -0.3 to VCC +0.3V Operating Temperature Range Commercial (J, K Version) ........................................... 0˚C to 70˚C Industrial (A, B Version) .......................................... -40˚C to +85˚C Lead Temperature (Solder 10Sec) ............................................ +300˚C Storage Temperature .................................................. -65˚C to +150˚C Power Dissipation to 70˚C ........................................................ 500mW SPECIFICATIONS Unless otherwise noted the following specifications apply for VCC=5V or 3.3V with limits applicable for Tmin to Tmax. Typical applies for Ta=25˚C. PARAMETERS DC ACCURACY Resolution Integral Linearity K,B VCC=5.0V VCC=3.3V MIN. TYP. MAX. MIN. TYP. MAX. 10 10 UNITS Bits +0.5 +1.0 +0.5 +1.0 LSB Differential Linearity Error K,B +0.6 +2.0 +0.6 +2.0 LSB Gain Error K,B +0.2 +2.0 +0.2 +2.0 LSB Offset Error K,B +0.6 +2.0 +0.6 +3.0 LSB ANALOG INPUT Input Signal FS Range Input Impedance On Channel Off Channel Input Bias Current Analog Input Range 0 VCC 0 CONDITIONS VCC 20 100 3 100 .001 1 -.05 VCC+.05 -.05 20 100 3 100 .001 1 VCC+.05 pF MΩ pF MΩ µA Volts In Parallel with 100MΩ In Parallel with 100MΩ MULTIPLEXER Crosstalk (fD = Nyquist) Feedthrough (fD = Nyquist) -90 -90 -90 -90 dB dB Off to On Channel Off to On Channel fD= Disturbance CONVERSION SPEED Sample Time 1.5 1.5 See Timing Diagrams Conversion Time 10 10 clock cycles clock cycles kHz µS µS µS Complete Cycle Clock Period Clock High Time Clock Low Time SP8537DS/03 29.5 2.25 1.0 1.0 6.66 10 4.5 4.5 SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 2 See Timing Diagrams See Timing Diagrams See Timing Diagrams See Timing Diagrams See Timing Diagrams © Copyright 2000 Sipex Corporation SPECIFICATIONS (cont.) Unless otherwise noted the following specifications apply for VCC=5V or 3.3V with limits applicable for Tmin to Tmax. Typical applies for Ta=25˚C. PARAMETERS DIGITAL INPUTS Input Low Voltage, VIL Input High Voltage, VIH Input Current IIN Input Capacitance DIGITAL OUTPUTS Data Format Data Coding VOH VOL VCC=5.0V VCC=3.3V MIN. TYP. MAX. MIN. TYP. MAX. UNITS 0.8 2.0 0.8 2.0 +2.0 +2.0 3.0 3.0 4.0 2.0 0.4 0.4 Volts Volts µA pF Volts Volts AC ACCURACY Spurious free Dynamic Range (SFDR) 71 72 dB Total Harmonic Distortion (THD) -67 -68 dB Signal to Noise & Distortion (SINAD) 59 59 dB Signal to Noise (SNR) 60 60 dB SAMPLING DYNAMICS Acquisition Time to 0.05% 2 -3dB Small Signal BW Aperture Delay Aperture Jitter Common-Mode Rejection Ratio POWER SUPPLIES VCC Supply Current Operation Mode 70 3.38 5 20 150 80 2 70 6.00 4 30 150 80 MHz nS pS dB See Timing Diagram VDD=5V ±5%, IOH=-0.4mA VDD=5V ±5%, IOH=+1.6mA For all FFT’s (Full Differential Mode) If VCC = 5V fsample = 25kHz fin = 12kHz If VCC = 3.3V fsample = 6.66kHz fin = 2.8kHz fCM = 12.5kHz @ 5 volts 2.8kHz @ 3.3 volts Volts +3.0 +5.0 +5.5 +3.0 +3.3 +5.5 250 400 100 300 µA (CS=0) 29.5kHz, 5 volt conversion rate. 6.66kHz 3.3 volts (CS=1) 0.001 0.5 0.001 0.5 µA Power Dissipation Operating Mode Shutdown Mode 1.25 0.33 0.99 1.7 mW µW SP8537DS/03 VDD=5V +5% VDD=5V +5% µs Shutdown Mode TEMPERATURE RANGE Commercial Industrial Storage CONDITIONS 2 2.5 0˚ to +70˚C -40˚ to +85˚C -65˚ to +150˚C 0˚ to +70˚C -40˚ to +85˚C -65˚ to +150˚C ˚C ˚C ˚C SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 3 © Copyright 2000 Sipex Corporation SPECIFICATIONS (cont.) Recommended Operating Conditions MIN. +3.0 VCC=3.3V TYP. MAX. +3.3 +5.5 PARAMETERS Supply Voltage fCLK Clock Frequency tCYC Total Cycle Time 33.9 150.2 µS tCLK Clock Period 2.25 10.0 µS ten SCLK to DOUT Enable ▼ MIN. +3.0 VCC=5.0V TYP. MAX. +5.0 +5.5 SYMBOL VCC 444 ▼ 100 UNITS Volts kHz 80 200 150 300 nS tDIS CSN to DOUT Hi-Z 80 200 150 300 nS tR DOUT Rise Time 5 25 10 50 nS tF DOUT Fall Time 5 25 10 50 nS tHDO DOUT Valid After SCLK 80 200 150 300 nS thDI Hold Time DIN After CLK^ 50 tsuCS Setup Time CSv Before CLK^ 100 tsuDI Setup Time, DIN Stable Before CLK^ 100 tWHCLK CLK High Time 1 4.5 µS tWLCLK CLK Low Time 1 4.5 µS tWHCS CS High Time between Data Transfers Cycles 100 150 nS tSAMPLE S/H Acquisition Time 1.5 1.5 SCLK Cycles tCONV ADC Conversion Time 10 10 SCLK Cycles ▼ 0 50 10 150 SP8537 GND 4 nS 15 nS PIN ASSIGNMENTS Pin 1- CS - Chip Select. CS 1 CH1 3 nS 150 PIN DESCRIPTION CH0 2 0 8 VCC/VREF 7 SCLK Pin 3- CH1 - Channel 1 6 DOUT Pin 4- GND - Ground 5 DIN Pin 2- CH0 - Channel 0 Pin 5- DIN - Data In Pin 6 - DOUT - Data Out Pin 7- SCLK - Serial Clock Pin 8- VCC/VREF - Supply & Reference Voltage SP8537DS/03 SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 4 © Copyright 2000 Sipex Corporation DESCRIPTION The device uses a capacitive DAC architecture which provides the sampling behavior. This results in full Nyquist performance at the fastest throughput rate (29.5 KHz) the device is capable of. The SP8537 is a 10 bit sampling ADC with a programmable two channel multiplexer and serial data interface. The ADC samples and converts 10 bits of data in 33.9 µS with a 5V supply voltage applied. The SP8537 will also operate at a 3.3V supply at 150.2µS throughput. The device automatically shuts down to a +0.5 µA (MAX) level as soon as the chip is deselected (CS=1). Serial data output is available in an MSB first format. The power supply voltage is variable from 3.0V to 5.5V which provides supply flexibility. At the 5.0V supply level, conversion plus sampling time is 33.9µS and supply current is 250µA (1.25 mW). With a 3.3V supply the conversion plus sampling time is 150.2µS and current is reduced to 150µA (0.5 mW). FEATURES The device features automatic shutdown and will shutdown to a +0.5 µA power level as CS is brought high (de-selected). Power is proportional to conversion duty cycle and varies from 250 µA at 34µS (Duty cycle = 100%) to 6.25µa at 1.4 ms (Duty cycle = 2.5%). Two program bits, which are shifted into the device prior to conversion, determine the input configuration. In the single ended MUX configuration the input signal will be applied to either channel 0 or channel 1 and will be ground referenced. The maximum full scale range is VCC. In the full differential mode, the signal will be applied between channel 0 and channel 1. The signals applied at each input may both be dynamic. This is in contrast with pseudo differential devices which must have input low held at a constant level during conversion. The converter will provide significant common mode rejection when used in full differential manner. Both inputs must remain between ground and VCC for proper conversion. MUX ADDRESSING Mux Addressing SGL/DIFF ODD/SIGN 0 0 0 1 1 0 1 1 Examples: Conversion rate 34 µS 68 µS 136 µS 1.4 mS Channel # 0 1 VINH VINL VINL VINH VINH VINH GND ICC @ 5V 250 µA 125 µA 62.5 µA 6.25 µA Duty Cycle 100% 50% 25% 2.5% Comments Full Differential Mode VINL VINL Single Ended Mux Mode ADC TRANSFER FUNCTION INPUT VOLTAGE (VINH-VINL)* INPUT VOLTAGE AT VCC/VREF = 5V OUTPUT CODE 0 LSB 1 LSB 512 LSB 1022 LSB 1023 LSB 0V 0.0049V 2.5000V 4.9902V 4.9951V 0000000000 0000000001 1000000000 1111111110 1111111111 * See Mux Addressing Table for a definition of VINH - VINL. SP8537DS/03 SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 5 © Copyright 2000 Sipex Corporation Full Differential Sampling The device is configured such that it delivers serial data MSB first requiring 15 clock periods for a full conversion. Please refer to the timing diagram. The SP8537 can be configured for single-ended sampling (i.e. CH0-ground or CH1-ground) or full differential sampling (CH0-CH1 or CH1CH0). In the full differential sampling configuration, both inputs are sampled and held simultaneously. Because of the balanced differential sampling, dynamic common mode noise riding along the input signal is cancelled above and beyond DC noise. This is a significant improvement over psuedo-differential sampling schemes, where the low side of the input must remain constant during the conversion, and therefore only DC noise (i.e. signal offset) is cancelled. If AC common mode noise is left to be converted along with the differental component, the output signal will be degraded. Circuit Operation The device will ignore any leading zeros applied to the DIN pin even if CS is low. After Chip Select Bar (CS) is brought low and the START bit is clocked in to the converter, the conversion sequence is initiated. Two additional bits are clocked in immediately following the START bit: SGL/DIFF and ODD/SIGN. The second and third bits clocked in determine the MUX configuration (see MUX addressing table). Please refer to the timing diagram. The SGL/DIFF bit when zero sets the input MUX for full differential mode and when one, sets the input MUX for single ended mode. The ODD/SIGN bit when zero sets channel zero as the positive input (ground referred for single ended operation and referred to channel one in differential mode). With the ODD/SIGN bit one, channel one will be the positive input (ground referred for single ended operation and referred to channel zero in differential mode). Full differential sampling allows flexibility in converting the input signal. If the signal low-side is already tied to a ground elsewhere in the system, it can be hardwired to the low side channel (i.e. CH0 or CH1) which acts as a signal ground sense, breaking a potential ground loop. It is also possible to drive the inputs balanced differential, as long as both inputs are within the power rails. In this configuration, both the high and low signals have the same impedance looking back to ground, and therefore pick up the same noise along the physical path from signal source (i.e. sensor, transducer, battery) to converter. This noise becomes common mode, and is cancelled out by the differential sampling of the SP8537. The SP8537 is a SAR converter with full differential multiplexed front end, capacitive DAC, precision comparator, Successive Approximations Register, control logic and data output register. After the input is sampled and held the conversion process begins. The DAC MSB is set and its output is compared with the signal input, if the DAC output is less than the input, the comparator outputs a one which is latched into the SAR and simultaneously made available at the ADC serial output pin. Each bit is tested in a similar manner until the SAR contains a code which represents the signal input to within +1/2 LSB. During this process the SAR content has been shifted out of the ADC serially. In the MSB first format the data will appear at the DOUT pin MSB through LSB in 15 clock periods. Note that the Chip Select Bar pin must be toggled high between conversions. The DOUT pin will be in a high impedance state whenever Chip Select Bar is high. After Chip Select Bar has been toggled and brought low again, the converter is ready to accept another START bit and begin a new conversion. SP8537DS/03 Layout Considerations To preserve the high resolution and linearity of the SP8537 attention must be given to circuit board layout, ground impedance and bypassing. A circuit board layout which includes separate analog and digital ground planes will prevent the coupling of noise into sensitive converter circuits and will help to preserve the dynamic performance of the device. In single ended mode, the analog input signal should be referenced to the ground pin of the converter. This prevents any voltage drops that occur in the power supply's common return from appearing in series with the input signal. SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 6 © Copyright 2000 Sipex Corporation combination of a 6.8µF tantalum and a 0.1µF ceramic capacitor. To maintain maximum system accuracy, the supply connected to the VCC pin should be well isolated from digital supplies and wide load variations. A separate conductor from the supply regulator to the A/D converter will limit the effects of digital switching elsewhere in the system. Power supply noise can degrade the converters performance. Especially corrupting are noise and spikes from a switching power supply. In full differential mode, the high and low side board traces should run close to each other, with the same layout. This will insure that any noise coupling will be common mode, and cancelled by the converters (patent pending) full differential architecture. If separate analog and digital ground planes are not possible, care should be used to prevent coupling between analog and digital signals. If analog and digital lines must cross, they should do so at right angles. Parallel analog and digital lines should be separated by a circuit board trace which is connected to common. To avoid introducing distortion when driving the A/D converter input, the input signal source should be able to charge the SP8537's equivalent 20 pF of input capacitance from zero volts to the signal level in 1.5 clock periods. The SP8537 VCC pin is also the reference pin for the device. This means that noise on the VCC pin will be proportionally represented as noise in the converters output data. A noise signal of 4.88mV (at a 5V supply) will produce 1 LSB of error in the output data. The VCC pin should be bypassed to the ground pin with a parallel LSB First Conversion MSB First Conversion SP8537 Timing Diagram SP8537DS/03 SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 7 © Copyright 2000 Sipex Corporation Icc versus Sampling Rate (clock rate = 500kHz) Vcc = 5V Icc versus Sampling Rate (clock rate = 100kHz) Vcc = 3.3V 80.0 70.0 50.0 Icc (µA) Icc (µA) 60.0 40.0 30.0 20.0 10.0 0.0 10 100 1000 200.0 180.0 160.0 140.0 120.0 100.0 80.0 60.0 40.0 20.0 0.0 10000 10 conversion time (µs) 100 10000 conversion time (µs) Vcc = 3.30V Vcc = 5.00V +1.0LSB +1.0LSB INLE INLE -1.0LSB +1.0LSB -1.0LSB +1.0LSB DNLE DNLE -1.0LSB -1.0LSB 0 512 0 1023 FFT 20 dB/div Vcc =5V 0dB FFT -20dB -160dB 0HZ SP8537DS/03 1.74kHz/div 13.9kHz 512 1023 FFT 20 dB/div Vcc =3V Spectral Density dB Spectral Density dB 1000 0dB FFT -20dB -160dB 0HZ SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 8 0.348kHx/div 2.78kHz © Copyright 2000 Sipex Corporation Gain Error vs. Temperature 2.00 240 1.50 LSB µA Icc vs. Temperature 250 230 1.00 220 0.50 210 0.00 200 -50 0 50 100 -50 0 Spurious Free Dynamic Range 1.00 80.00 0.75 75.00 70.00 dB LSB Offset vs. Temperature 0.50 65.00 0.25 60.00 55.00 0 -50 0 50 100 50.00 1000 10000 Frequency temperature (C) dB 70.00 68.00 66.00 64.00 62.00 60.00 58.00 56.00 54.00 52.00 50.00 1000 10000 Frequency 100000 Signal to Noise Ratio SINAD dB 100 temperature (C) temperature (C) 70.00 68.00 66.00 64.00 62.00 60.00 58.00 56.00 54.00 52.00 50.00 100000 1000 100 -55.00 CMRR (dB) -60.00 -65.00 -70.00 -75.00 10000 Frequency 100000 Input CMRR, Vcc = 5V Total Harmonic Distortion -50.00 dB 50 80 60 40 20 0 -80.00 1000 SP8537DS/03 10000 Frequency 100000 1E1 1E2 1E3 1E4 1E5 1E6 1E7 1E8 Input CMFrequency SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 9 © Copyright 2000 Sipex Corporation PACKAGE: PLASTIC SMALL OUTLINE (SOIC) (NARROW) E H h x 45° D A Ø e B DIMENSIONS (Inches) Minimum/Maximum (mm) SP8537DS/03 A1 L 8–PIN 14–PIN 16–PIN A 0.053/0.069 (1.346/1.748) 0.053/0.069 (1.346/1.748) 0.053/0.069 (1.346/1.748) A1 0.004/0.010 (0.102/0.249 0.004/0.010 (0.102/0.249) 0.004/0.010 (0.102/0.249) B 0.014/0.019 (0.35/0.49) 0.013/0.020 (0.330/0.508) 0.013/0.020 (0.330/0.508) D 0.189/0.197 (4.80/5.00) 0.337/0.344 0.386/0.394 (8.552/8.748) (9.802/10.000) E 0.150/0.157 (3.802/3.988) 0.150/0.157 (3.802/3.988) 0.150/0.157 (3.802/3.988) e 0.050 BSC (1.270 BSC) 0.050 BSC (1.270 BSC) 0.050 BSC (1.270 BSC) H 0.228/0.244 (5.801/6.198) 0.228/0.244 (5.801/6.198) 0.228/0.244 (5.801/6.198) h 0.010/0.020 (0.254/0.498) 0.010/0.020 (0.254/0.498) 0.010/0.020 (0.254/0.498) L 0.016/0.050 (0.406/1.270) 0.016/0.050 (0.406/1.270) 0.016/0.050 (0.406/1.270) Ø 0°/8° (0°/8°) 0°/8° (0°/8°) 0°/8° (0°/8°) SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 10 © Copyright 2000 Sipex Corporation PACKAGE: PLASTIC DUAL–IN–LINE (NARROW) E1 E D1 = 0.005" min. (0.127 min.) A1 = 0.015" min. (0.381min.) D A = 0.210" max. (5.334 max). C A2 L B1 B e = 0.100 BSC (2.540 BSC) Ø eA = 0.300 BSC (7.620 BSC) ALTERNATE END PINS (BOTH ENDS) DIMENSIONS (Inches) Minimum/Maximum (mm) 8–PIN 14–PIN 16–PIN 18–PIN 20–PIN 22–PIN A2 0.115/0.195 (2.921/4.953) 0.115/0.195 (2.921/4.953) 0.115/0.195 (2.921/4.953) 0.115/0.195 (2.921/4.953) 0.115/0.195 (2.921/4.953) 0.115/0.195 (2.921/4.953) B 0.014/0.022 (0.356/0.559) 0.014/0.022 (0.356/0.559) 0.014/0.022 (0.356/0.559) 0.014/0.022 (0.356/0.559) 0.014/0.022 (0.356/0.559) 0.014/0.022 (0.356/0.559) B1 0.045/0.070 (1.143/1.778) 0.045/0.070 (1.143/1.778) 0.045/0.070 (1.143/1.778) 0.045/0.070 (1.143/1.778) 0.045/0.070 (1.143/1.778) 0.045/0.070 (1.143/1.778) C 0.008/0.014 (0.203/0.356) 0.008/0.014 (0.203/0.356) 0.008/0.014 (0.203/0.356) 0.008/0.014 (0.203/0.356) 0.008/0.014 (0.203/0.356) 0.008/0.014 (0.203/0.356) D 0.355/0.400 0.735/0.775 0.780/0.800 0.880/0.920 0.980/1.060 1.145/1.155 (9.017/10.160) (18.669/19.685) (19.812/20.320) (22.352/23.368) (24.892/26.924) (29.083/29.337) E 0.300/0.325 (7.620/8.255) 0.300/0.325 (7.620/8.255) 0.300/0.325 (7.620/8.255) 0.300/0.325 (7.620/8.255) 0.300/0.325 (7.620/8.255) 0.300/0.325 (7.620/8.255) E1 0.240/0.280 (6.096/7.112) 0.240/0.280 (6.096/7.112) 0.240/0.280 (6.096/7.112) 0.240/0.280 (6.096/7.112) 0.240/0.280 (6.096/7.112) 0.240/0.280 (6.096/7.112) L 0.115/0.150 (2.921/3.810) 0.115/0.150 (2.921/3.810) 0.115/0.150 (2.921/3.810) 0.115/0.150 (2.921/3.810) 0.115/0.150 (2.921/3.810) 0.115/0.150 (2.921/3.810) Ø 0°/ 15° (0°/15°) 0°/ 15° (0°/15°) 0°/ 15° (0°/15°) 0°/ 15° (0°/15°) 0°/ 15° (0°/15°) 0°/ 15° (0°/15°) SP8537DS/03 SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 11 © Copyright 2000 Sipex Corporation ORDERING INFORMATION Model ........................................................ Linearity (LSB) ..................... Temperature Range ............................................................... Package SP8537BN .......................................................... ±1.0 .................................... –40˚C to +85˚C .............................................. 8-pin, 0.3" Plastic DIP SP8537KN .......................................................... ±1.0 ..................................... –0˚C to +70˚C ............................................... 8-pin, 0.3" Plastic DIP SP8537BS .......................................................... ±1.0 .................................... –40˚C to +85˚C ......................................... 8-pin, 0.15" Plastic SOIC SP8537KS .......................................................... ±1.0 ..................................... –0˚C to +70˚C .......................................... 8-pin, 0.15" Plastic SOIC Please consult the factory for pricing and availability on a Tape-On-Reel option. The information furnished herein by Sipex has been carefully reviewed for accuracy and reliability. Its application or use, however, is solely the responsibility of the user. No responsibility for use of this information is assumed by Sipex, and this information shall not explicitly or implicitly become part of the terms and conditions of any subsequent sales agreement with Sipex. By the sale or transfer of this information, Sipex assumes no responsibility for any infringement of patents or other rights of third parties which may result from its use. No license or other proprietary rights are granted by implication or otherwise under any patent or patent rights of Sipex Corporation. Life Support Policy: Sipex Corporation does not authorize or warrant any Sipex product for use in life support devices and/or systems without the express written approval of the President of Sipex Corporation. Life support devices or systems are devices which: - are intended for surgical implant into the body or - are intended to support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the appropriate documentation can be reasonably expected to result in significant injury to the user. Corporation SIGNAL PROCESSING EXCELLENCE Sipex Corporation Headquarters and Sales Office 22 Linnell Circle Billerica, MA 01821 TEL: (978) 667-8700 FAX: (978) 670-9001 e-mail: [email protected] Sales Office 233 South Hillview Drive Milpitas, CA 95035 TEL: (408) 934-7500 FAX: (408) 935-7600 Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described hereing; neither does it convey any license under its patent rights nor the rights of others. SP8537DS/03 SP8537 Micropower Sampling 10–Bit Voltage A/D Converter 12 © Copyright 2000 Sipex Corporation