MAX1284ACSA+

19-1687; Rev 1; 7/00 KIT ATION EVALU LE B A IL A AV 400ksps/300ksps, Single-Supply, Low-Power, Serial 12-Bit ADCs with Internal Reference The MAX1284/MAX1285 12-bit analog-to-digital converters (ADCs) combine a high-bandwidth track/hold (T/H), a serial interface with high conversion speed, an internal +2.5V reference, and low power consumption. The MAX1284 operates from a single +4.5V to +5.5V supply. The MAX1285 operates from a single +2.7V to +3.6V supply. The 3-wire serial interface connects directly to SPI™/QSPI™/ MICROWIRE™ devices without external logic. The devices use an external serial-interface clock to perform successive-approximation analog-to-digital conversions. Low power, ease of use, and small package size make these converters ideal for remote-sensor and data-acquisition applications or for other circuits with demanding power consumption and space requirements. The MAX1284/MAX1285 are available in 8-pin SO packages. These devices are pin-compatible, higher-speed versions of the MAX1240/MAX1241. Refer to the respective data sheets for more information. ____________________________Features ♦ Single-Supply Operation +4.5V to +5.5V (MAX1284) +2.7V to +3.6V (MAX1285) ♦ ±1LSB (max) DNL, ±1LSB (max) INL ♦ 400ksps Sampling Rate (MAX1284) ♦ Internal Track/Hold ♦ +2.5V Internal Reference ♦ Low Power: 2.5mA (400ksps) ♦ SPI/QSPI/MICROWIRE 3-Wire Serial-Interface ♦ Pin-Compatible, High-Speed Upgrades to MAX1240/MAX1241 ♦ 8-Pin SO Package Ordering Information Applications Portable Data Logging Data Acquisition Medical Instruments Battery-Powered Instruments Pen Digitizers PART TEMP. RANGE PINSUPPLY PACKAGE VOLTAGE (V) MAX1284BCSA 0°C to +70°C 8 SO 5 MAX1284BESA* -40°C to +85°C 8 SO MAX1285BCSA 0°C to +70°C 5 8 SO 2.7 to 3.6 MAX1285BESA -40°C to +85°C 8 SO *Future product—contact factory for availability. Process Control Pin Configuration 2.7 to 3.6 Functional Diagram VDD 1 TOP VIEW VDD 1 AIN 2 SHDN 3 MAX1284 MAX1285 REF 4 8 SCLK 7 CS 6 DOUT 5 GND CS SCLK SHDN SO AIN 8 3 2 INT CLOCK CONTROL LOGIC T/H REF OUTPUT SHIFT REGISTER 6 DOUT 12-BIT SAR MAX1284 MAX1285 +2.5V REFERENCE SPI and QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp. 7 4 5 GND ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX1284/MAX1285 General Description MAX1284/MAX1285 400ksps/300ksps, Single-Supply, Low-Power, Serial 12-Bit ADCs with Internal Reference ABSOLUTE MAXIMUM RATINGS VDD to GND .............................................................-0.3V to +6V AIN to GND................................................-0.3V to (VDD + 0.3V) REF to GND ...............................................-0.3V to (VDD + 0.3V) Digital Inputs to GND...............................................-0.3V to +6V DOUT to GND............................................-0.3V to (VDD + 0.3V) DOUT Current ..................................................................±25mA Continuous Power Dissipation (TA = +70°C) 8-Pin SO (derate 5.88mW/°C above +70°C) ..............471mW Operating Temperature Ranges MAX1284BCSA/MAX1285BCSA .......................0°C to +70°C MAX1284BESA/MAX1285BESA .....................-40°C to +85°C Storage Temperature Range............................-60°C to +150°C Lead Temperature (soldering, 10s) ................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS—MAX1284 (VDD = +4.5V to +5.5V; fSCLK = 6.4MHz, 50% duty cycle, 16 clocks/conversion cycle (400ksps), 4.7µF capacitor at REF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC ACCURACY (Note 1) Resolution 12 Relative Accuracy (Note 2) INL Differential Nonlinearity DNL Bits ±1.0 LSB ±1.0 LSB Offset Error ±6.0 LSB Gain Error (Note 3) ±6.0 LSB No missing codes over temperature Gain Error Temperature Coefficient ±0.8 ppm/°C 70 dB DYNAMIC SPECIFICATIONS (100kHz sine wave, 2.5Vp-p, clock = 6.4MHz) Signal-to-Noise Plus Distortion Ratio SINAD Total Harmonic Distortion THD Spurious-Free Dynamic Range SFDR Intermodulation Distortion IMD Up to the 5th harmonic fIN1 = 99Hz, fIN2 = 102Hz Full-Power Bandwidth -3dB point Full-Linear Bandwidth SINAD > 68dB -80 dB 80 dB 76 dB 6 MHz 350 kHz CONVERSION RATE Conversion Time (Note 4) tCONV Track/Hold Acquisition Time tACQ 2.5 Aperture Delay 10 Aperture Jitter Serial Clock Frequency µs 468 ns 68dB CONVERSION RATE Conversion Time (Note 4) tCONV Track/Hold Acquisition Time tACQ 3.3 tSCLK Duty Cycle µs 625 ns 10 ns