2 LC MOS 12-Bit, Serial 6 ms a ADC in 8-Pin Package AD7893 FUNCTIONAL BLOCK DIAGRAM FEATURES Fast 12-Bit ADC with 6 ms Conversion Time REF IN V DD 8-Pin Mini-DlP and SOIC Single Supply Operation AD7893 High Speed, Easy-to-Use, Serial Interface On-Chip Track/Hold Amplifier TRACK/ Selection of Input Ranges HOLD SIGNAL V IN SCALING* 12-BIT 610 V for AD7893-10 ADC 62.5 V for AD7893-3 0 V to +2.5 V for AD7893-2 0 V to +5 V for AD7893-5 OUTPUT CONVST REGISTER Low Power: 25 mW typ AGND DGND SCLK SDATA *AD7893-5, AD7893-10, AD7893-3 PRODUCT HIGHLIGHTS GENERAL DESCRIPTION 1. Fast, 12-Bit ADC in 8-Pin Package The AD7893 is a fast, 12-bit ADC that operates from a single The AD7893 contains a 6 s ADC, a track/hold amplifier, +5 V supply and is housed in a small 8-pin mini-DIP and 8-pin control logic and a high speed serial interface, all in an 8-pin SOIC. The part contains a 6 s successive approximation A/D package. This offers considerable space saving over alterna- converter, an on-chip track/hold amplifier, an on-chip clock and tive solutions. a high speed serial interface. 2. Low Power, Single Supply Operation Output data from the AD7893 is provided via a high speed, The AD7893 operates from a single +5 V supply and con- serial interface port. This two-wire serial interface has a serial sumes only 25 mW. This low power, single supply operation clock input and a serial data output with the external serial clock makes it ideal for battery powered or portable applications. accessing the serial data from the part. 3. High Speed Serial Interface In addition to traditional dc accuracy specifications such as lin- The part provides high speed serial data and serial clock lines, earity, full-scale and offset errors, the AD7893 is also specified allowing for an easy, two-wire serial interface arrangement. for dynamic performance parameters, including harmonic dis- tortion and signal-to-noise ratio. The part accepts an analog input range of 10 V (AD7893-10), 2.5 V (AD7893-3), 0 V to +5 V (AD7893-5) or 0 V to +2.5 V (AD7893-2) and operates from a single +5 V supply, consuming only 25 mW typical. The AD7893 is fabricated in Analog Devices Linear Compat- 2 ible CMOS (LC MOS) process, a mixed technology process that combines precision bipolar circuits with low power CMOS logic. The part is available in a small, 8-pin, 0.3 wide, plastic or hermetic dual-in-line package (mini-DIP) and in an 8-pin, small outline IC (SOIC). REV. E Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. which may result from its use. No license is granted by implication or Tel: 617/329-4700 World Wide Web Site: (V = +5 V, AGND = DGND = 0 V, REF IN = +2.5 V. All specifications T to T unless DD MIN MAX AD7893SPECIFICATIONS otherwise noted.) AB S l Parameter Versions Versions Version Units Test Conditions/Comments DYNAMIC PERFORMANCE 2 Signal to (Noise + Distortion) Ratio +25C 70 70 70 dB min f = 10 kHz Sine Wave, f = 117 kHz IN SAMPLE 2 Total Harmonic Distortion (THD) 80 80 80 dB max f = 10 kHz Sine Wave, f = 117 kHz IN SAMPLE 2 Peak Harmonic or Spurious Noise 80 80 80 dB max f = 10 kHz Sine Wave, f = 117 kHz IN SAMPLE 2 Intermodulation Distortion (IMD) fa = 9 kHz, fb = 9.5 kHz, f = 117 kHz SAMPLE 2nd Order Terms 80 80 80 dB max 3rd Order Terms 80 80 80 dB max DC ACCURACY Resolution 12 12 12 Bits Minimum Resolution for which No Missing Codes are Guaranteed 12 12 12 Bits 2 Relative Accuracy 1 1/2 1 LSB max 2 Differential Nonlinearity 1 1 1 LSB max 2 Positive Full-Scale Error 3 1.5 3 LSB max AD7893-2, AD7893-5 Unipolar Offset Error 4 3 4 LSB max AD7893-10, AD7893-3 2 Negative Full-Scale Error 3 1.5 3 LSB max Bipolar Zero Error 4 2 4 LSB max ANALOG INPUT AD7893-10 Input Voltage Range 10 10 10 Volts Input Resistance 16 16 16 k min AD7893-3 Input Voltage Range 2.5 2.5 2.5 Volts Input Resistance 4 4 4 k min AD7893-5 Input Voltage Range 0 to +5 0 to +5 0 to +5 Volts Input Resistance 9 9 9 k min AD7893-2 Input Voltage Range 0 to +2.5 0 to +2.5 0 to +2.5 Volts Input Current 500 500 500 nA max REFERENCE INPUT REF IN Input Voltage Range 2.375/2.625 2.375/2.625 2.375/2.625 V min/V max 2.5 V 5% Input Current 2 2 10 A max 3 Input Capacitance 10 10 10 pF max LOGIC INPUTS Input High Voltage, V 2.4 2.4 2.4 V min V = 5 V 5% INH DD Input Low Voltage, V 0.8 0.8 0.8 V max V = 5 V 5% INL DD Input Current, I 10 10 10 A max V = 0 V to V IN IN DD 3 Input Capacitance, C 10 10 10 pF max IN LOGIC OUTPUTS Output High Voltage, V 4.0 4.0 4.0 V min I = 200 A OH SOURCE Output Low Voltage, V 0.4 0.4 0.4 V max I = 1.6 mA OL SINK Output Coding AD7893-10, AD7893-3 2s Complement AD7893-2, AD7893-5 Straight (Natural) Binary CONVERSION RATE Conversion Time 6 6 6 s max 2 Track/Hold Acquisition Time 1.5 1.5 1.5 s max POWER REQUIREMENTS V +5 +5 +5 V nom 5% for Specified Performance DD I 9 9 9 mA max DD Power Dissipation 45 45 45 mW max Typically 25 mW NOTES 1 Temperature Ranges are as follows: A, B Versions: 40C to +85C, S Version: 55C to +125C. 2 See Terminology. 3 Sample tested +25C to ensure compliance. Specifications subject to change without notice. 2 REV. E