ANALOG Low Cost Signal DEVICES Conditioning 8-Bit ADC AD670 1.1 Scope. This specification covers the detail requirements for a complete single supply 8-bit resolution A/D converter with an instrumentation input amplifier, and complete microprocessor interface. 1.2 Part Number. The complete part number per Table 1 of this specification is as follows: Device Part Number! -1 AD670SCX)/883B NOTE 'See paragraph 1.2.3 for package identifier. 1.2.3 Case Outline. See Appendix 1 of General Specification ADI-M-1000: package outline: & Package Description D D-20 20-Pin DIP E E-20A 20-Terminal LCC 1.3 Absolute Maximum Ratings. (T,= + 25C unless otherwise noted) Veco toGround 26. ee ee ee ee OV to +7.5V Digital Inputs (Pins 11-15) 2. ee ee ee 0.5V to Voc +0.5V Digital Outputs (Pins 1-9). 2. 2. ee ee ee Momentary Short to Vcp or Ground Analog Inputs (Pins 16-19) 2... ee ee ee ee 30V to +30V Power Dissipation... 1. 1 ee et 450mW Storage Temperature Range... 2 0. ee ee ee - 65C to + 150C Lead Temperature Range (Soldering to Specs) ... 6 1 ee ee es + 300C 1.5 Thermal Characteristics. Thermal Resistance @j- = 25C/W Oya = 85C/W REV. C ANALOG-TO-DIGITAL CONVERTERS 6-25 ANALOG-TO-DIGITAL CONVERTERS aAD670 SPECIFICATIONS Table 1. Design Sub Sub Sub Sub Limit Group |Group |Group | Group Test Symbol} Device] @+2SC | 1 2,3 9 10,11 | Test Condition Units Relative Accuracy RA -1 V2 12 1 + LSB max Differential Nonlinearity* DNL | -1 8 8 8 + Bits max Gain Error? Ag -1 1.5 1.5 2.5 + LSB max Unipolar Offset Error Org -1 1 1 2 2.55V Input Range + LSB max Bipolar Zero Error Bpoz | -1 1 1 2 +1.28V FS + LSB max Input Resistance Rw -1 8 8 8 2.55V Input Range kQ min 12 12 12 2.55V Input Range kQ max Input Bias Current Ig -1 750 750 750 255mV Input Range +nA max Input Offset Current los -1 200 200 200 +nA max Absolute Input Signal Range* | Vaps -) 0.34 0.34 0.15 255mV Input Range -Vmin Veo-3.3 | Veco- 3.3] Vec - 3.5 255mV Input Range + Vmax 3.4 3.4 1.5 2.55V Input Range Vmin Vec Vec Voc 2.55V Input Range +V max Common-Mode Rejection CMR | -} I 18 2 255mV + LSB max Three-State Leakage Current | Ioz -1 40 40 40 +pA max Power Supply Rejection Ratio | PSRR | -1 0.015 0.015 0.015 2.55V FS + %FS/% max Voc = +4.75V to +5.5V Power Supply Current lec -1 45 45 45 +mA max Digital Input High Voltage Vin -1 2.0 2.0 2.0 +Vmin Digital Input Low Vir -1 0.8 0.8 0.7 +V max Digital Input High Current lu -1 100 100 100 +A max Digital Input Low Current li -1 100 100 100 ~ pA min Digital Output Low Voltage Von. -1 0.4 0.4 0.4 lo. = 1.6mA + Vmax Digital Output High Voltage Vou -1 2.4 2.4 2.4 Tou = 0.5mA +Vmin Conversion Time TC -1 10 10 13 Ss max Write/Start Pulse Width tw -1 300 300 300 See Note 6 ns min Input Data Setup Time tps -} 200 ns min Input Data Hold Time tou -) 10 ns min Read/Write Setup Before Control trwe -1 0 ns min Status Delay toc 1 700 ns max Delay From Status to Data Read tsp -1 250 ns max Bus Access Time trp -1 250 250 ns max Data Hold Time toy -1 25 ns max Output Float Delay tor -1 150 150 ns max Read Time -1 250 ns min NOTES 'Ta= +25C, Vs= + 5V. ?Tested on both 2.56V full scale and + 1.28V full scale. Minimum resolution for which there are no missing codes. Input signal range is with respect to Power Ground (Pin 10). 5Digital output code will not change by more than ILSB with full scale applied to the differential inputs over the input signal range. Timing per Figures 1, 2 or 3. Vom =0to 0.34V; Vey =0t0 Voc 3.6V. Vcm =0to 0,15V3 Vem = 0t0 Voc 3.8V. 6-26 ANALOG-TO-DIGITAL CONVERTERS REV. C| AD670 3.2.1 Functional Block Diagrams and Terminal Assignments. cE = AW FORMAT BPOWPO a z [es] 14 [3] fe] [fe] 43 3 3 >> x T tf aaat3 ~ Vou Ht | 16 32 1 20 18 CONTROL M Viy LOW [7] LoGic rs] STATUS cao [a D3 4 t 18 +Vy HI pas 17 -Vin LOW +Vyy LOW | 19 AD670 re 05 6 ToP VIEW 16 ~ Vi HI 067 {Not to Scale) 15 cS 7] v7 ase) D7 (MSB) a 14 CE SUCCESSIVE. a, | THREE | 8,t. APPROXIMATION aye, oe REGISTER BUFFER to. 9 10 17 12 13 [+ | 00 s81 83 ig = | VOLTAGE a 2'2 3 REFERENCE 5 2 6 D670 3 a }r0j [20] POWER GND +Vcc 3.2.4 Microcircuit Technology Group. This microcircuit is covered by technology group (57). 4.2.1 Life Test/Burn-In Circuit. Steady state life test is per MIL-STD-883 Method 1005. Burn-in is per MIL-STD-883 Method 1015 test condition (B). O.1pF +5V 47pF t MR-820 GND ALL RESISTORS ARE 3k2), 1%, 1/4 WATT. REV. C ANALOG-TO-DIGITAL CONVERTERS 6-27 ANALOG-TO-DIGITAL CONVERTERS aAD670 \ Figure 1. Convert Timing Figure 2. Read Timing Rw 1 T ee ! _ cE, ! ! (Low) WRITE READ 1 \ | I STATUS | | 4 | C nara Ven) ZEEE. a aml tor bee Figure3. Stand-Alone Timing Table 2. AD670 Control Signal Truth Table Table 3. Differential Input Signal Range ww | cs cE OPERATION Mode Range | Min | Max | Unit 0 0 0 WRITE/CONVERT Unipolar | LOW | 0 255 mV 1 0 0 READ Unipolar | HIGH | 0 2.55 Vv x x 1 NONE Bipolar LOW | ~128 | 127 mV x 1 x NONE Bipolar HIGH | ~1.28| 1.27 Vv 6-28 ANALOG-TO-DIGITAL CONVERTERS REV. C