MAX1270/MAX1271 19-4782 Rev 2 9/04 Multirange, +5V, 8-Channel, Serial 12-Bit ADCs General Description Features The MAX1270/MAX1271 are multirange, 12-bit data- 12-Bit Resolution, 0.5 LSB Linearity acquisition systems (DAS) that require only a single +5V Single-Supply Operation +5V supply for operation, yet accept signals at their analog inputs that can span above the power-supply SPI/QSPI and MICROWIRE-Compatible rail and below ground. These systems provide eight 3-Wire Interface analog input channels that are independently software Four Software-Selectable Input Ranges programmable for a variety of ranges: 10V, 5V, 0 to +10V, 0 to +5V for the MAX1270 V , V /2, 0 to MAX1270: 0 to +10V, 0 to +5V, 10V, 5V REF REF V , 0 to V /2 for the MAX1271. This range switch- REF REF MAX1271: 0 to V , 0 to V /2, V , REF REF REF ing increases the effective dynamic range to 14 bits and V /2 REF provides the flexibility to interface 420mA, 12V, and Eight Analog Input Channels 15V powered sensors directly to a single +5V system. In addition, these converters are fault protected to 110ksps Sampling Rate 16.5V a fault condition on any channel will not affect 16.5V Overvoltage-Tolerant Input Multiplexer the conversion result of the selected channel. Other fea- tures include a 5MHz bandwidth track/hold, software- Internal 4.096V or External Reference selectable internal/external clock, 110ksps throughput Two Power-Down Modes rate, and internal 4.096V or external reference operation. Internal or External Clock The MAX1270/MAX1271 serial interface directly connects to SPI/QSPI and MICROWIRE devices 24-Pin Narrow PDIP or 28-Pin SSOP Packages without external logic. A hardware shutdown input (SHDN) and two software- programmable power-down modes, standby (STBYPD) Typical Operating Circuit or full power-down (FULLPD), are provided for low-cur- +5V rent shutdown between conversions. In standby mode, the reference buffer remains active, eliminating startup delays. 0.1F The MAX1270/MAX1271 are available in 24-pin narrow PDIP or space-saving 28-pin SSOP packages. V DD SHDN Applications CH0 Industrial Control Systems Automatic Testing CH1 CH2 Data-Acquisition Systems Robotics ANALOG MAX1270 CH3 Battery-Powered Medical Instruments INPUTS MAX1271 CH4 Instruments CH5 CH6 CH7 MC68HCXX CS I/O Ordering Information SCLK SCK DIN MOSI INL REF DOUT MISO PART TEMP RANGE PIN-PACKAGE (LSB) REFADJ SSTRB MAX1270ACNG 0C to +70C 24 Narrow PDIP 0.5 4.7 F 0.01 F AGND DGND MAX1270BCNG 0C to +70C 24 Narrow PDIP 1 MAX1270ACAI 0C to +70C 28 SSOP 0.5 MAX1270BCAI 0C to +70C 28 SSOP 1 Ordering Information continued at end of data sheet. Pin Configurations appear at end of data sheet. SPI and QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLEMultirange, +5V, 8-Channel, Serial 12-Bit ADCs ABSOLUTE MAXIMUM RATINGS V to AGND............................................................-0.3V to +6V Operating Temperature Ranges DD AGND to DGND.....................................................-0.3V to +0.3V MAX127 C ......................................................0C to +70C CH0CH7 to AGND ......................................................... 16.5V MAX127 E ......................................................-40C to +85C REF, REFADJ to AGND ..............................-0.3V to (V + 0.3V) Storage Temperature Range .............................-65C to +150C DD SSTRB, DOUT to DGND.............................-0.3V to (V + 0.3V) DD Lead Temperature (soldering, 10s) .................................+300C SHDN, CS, DIN, SCLK to DGND..............................-0.3V to +6V Max Current into Any Pin ....................................................50mA Continuous Power Dissipation (T = +70C) A 24-Pin Narrow DIP (derate 13.33mW/C above +70C)..1067mW 28-Pin SSOP (derate 9.52mW/C above +70C) ..........762mW 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 (V = +5.0V 5% unipolar/bipolar range external reference mode, V = +4.096V 4.7F at REF external clock f = 2.0MHz, DD REF CLK 50% duty cycle (MAX127 B) f = 1.8MHz, 50% duty cycle (MAX127 A) 18 clock/conversion cycle, T = T to T , unless CLK A MIN MAX otherwise noted. Typical values are T = +25C.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS ACCURACY (Note 1) Resolution 12 Bits MAX127 A 0.5 Integral Nonlinearity INL LSB MAX127 B 1.0 Differential Nonlinearity DNL No missing codes over temperature 1 LSB MAX127 A 3 Unipolar MAX127 B 5 Offset Error LSB MAX127 A 5 Bipolar MAX127 B 10 Unipolar 0.1 Channel-to-Channel Offset Error LSB Matching Bipolar 0.3 MAX127 A 7 Unipolar MAX127 B 10 Gain Error (Note 2) LSB MAX127 A 7 Bipolar MAX127 B 10 Unipolar, external reference 3 Gain Error Temperature ppm/C Coefficient (Note 2) Bipolar, external reference 5 DYNAMIC SPECIFICATIONS (10kHz sine-wave input, 10V (MAX1270), or 4.096V (MAX1271), f = 110ksps P-P P-P SAMPLE (MAX127 B), f = 100ksps (MAX127 A)) SAMPLE Signal-to-Noise + Distortion Ratio SINAD 70 dB Total Harmonic Distortion THD Up to the 5th harmonic -87 -78 dB Spurious-Free Dynamic Range SFDR 80 dB 50kHz (Note 3) -86 Channel-to-Channel Crosstalk dB DC, V = 16.5V -96 IN Aperture Delay External clock mode 15 ns External clock mode <50 ps Aperture Jitter Internal clock mode 10 ns 2 MAX1270/MAX1271