MAX1268ACEG+

19-2722; Rev 0; 04/03 420ksps, +5V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface Power consumption is only 10mW at the maximum sampling rate of 420ksps. Two software-selectable powerdown modes enable the MAX1266/MAX1268 to be shut down between conversions; accessing the parallel interface returns them to normal operation. Powering down between conversions can reduce supply below 10µA at lower sampling rates. Both devices offer software-configurable analog inputs for unipolar/bipolar and single-ended/pseudo-differential operation. In single-ended mode, the MAX1266 has six input channels and the MAX1268 has two (three input channels and one input channel, respectively, when in pseudo-differential mode). Excellent dynamic performance and low power, combined with ease of use and small package size, make these converters ideal for battery-powered and dataacquisition applications or for other circuits with demanding power-consumption and space requirements. The MAX1266 is offered in a 28-pin QSOP package, while the MAX1268 is available in a 24-pin QSOP. For pin-compatible +3V, 12-bit versions, see the MAX1265/MAX1267. Features ♦ 12-Bit Resolution, ±0.5 LSB Linearity ♦ Single +5V Operation ♦ Internal +2.5V Reference ♦ Software-Configurable Analog Input Multiplexer 6-Channel Single Ended/ 3-Channel Pseudo-Differential (MAX1266) 2-Channel Single Ended/ 1-Channel Pseudo-Differential (MAX1268) ♦ Software-Configurable Unipolar/Bipolar Analog Inputs ♦ Low Current 2.8mA (420ksps) 1.0mA (100ksps) 400µA (10ksps) 2µA (Shutdown) ♦ Internal 6MHz Full-Power Bandwidth Track/Hold ♦ Parallel 12-Bit Interface ♦ Small Footprint 28-Pin QSOP (MAX1266) 24-Pin QSOP (MAX1268) Pin Configurations TOP VIEW Applications D9 1 24 D10 Industrial Control Systems Data Logging D8 2 23 D11 Energy Management Patient Monitoring D7 3 22 VDD Data-Acquisition Systems Touch Screens D6 4 21 REF D5 5 Ordering Information PART TEMP RANGE MAX1266ACEI 0°C to +70°C 28 QSOP INL (LSB) ±0.5 MAX1266BCEI 0°C to +70°C 28 QSOP ±1 MAX1266AEEI -40°C to +85°C 28 QSOP ±0.5 MAX1266BEEI -40°C to +85°C 28 QSOP ±1 MAX1268ACEG 0°C to +70°C 24 QSOP ±0.5 MAX1268BCEG 0°C to +70°C 24 QSOP ±1 MAX1268AEEG -40°C to +85°C 24 QSOP ±0.5 MAX1268BEEG -40°C to +85°C 24 QSOP ±1 PIN-PACKAGE D4 6 20 REFADJ MAX1268 19 GND D3 7 18 COM D2 8 17 CH0 D1 9 16 CH1 D0 10 15 CS INT 11 14 CLK RD 12 13 WR QSOP Pin Configurations continued at end of data sheet. Typical Operating Circuits appear at end of data sheet. ________________________________________________________________ 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 MAX1266/MAX1268 General Description The MAX1266/MAX1268 low-power, 12-bit analog-todigital converters (ADCs) feature a successive-approximation ADC, automatic power-down, fast wake-up (2µs), an on-chip clock, +2.5V internal reference, and a high-speed 12-bit parallel interface. They operate with a single +5V analog supply. MAX1266/MAX1268 420ksps, +5V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface ABSOLUTE MAXIMUM RATINGS VDD to GND ..............................................................-0.3V to +6V CH0–CH5, COM to GND ............................-0.3V to (VDD + 0.3V) REF, REFADJ to GND.................................-0.3V to (VDD + 0.3V) Digital Inputs to GND ...............................................-0.3V to +6V Digital Outputs (D0–D11, INT) to GND.......-0.3V to (VDD + 0.3V) Continuous Power Dissipation (TA = +70°C) 24-Pin QSOP (derate 9.5mW/°C above +70°C)..........762mW 28-Pin QSOP (derate 8.0mW/°C above +70°C)..........667mW Operating Temperature Ranges MAX1266_C_ _/MAX1268_C_ _ .........................0°C to +70°C MAX1266_E_ _/MAX1268_E_ _ ......................-40°C to +85°C Storage Temperature Range .............................-65°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 (VDD = +5V ±10%, COM = GND, REFADJ = VDD, VREF = +2.5V, 4.7µF capacitor at REF pin, fCLK = 7.6MHz (50% duty cycle), 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 RES Relative Accuracy (Note 2) INL Differential Nonlinearity DNL 12 Bits MAX126_A ±0.5 MAX126_B ±1 No missing codes overtemperature ±1 LSB ±4 LSB Offset Error Gain Error ±4 (Note 3) LSB LSB Gain Temperature Coefficient ±2.0 ppm/°C Channel-to-Channel Offset Matching ±0.2 LSB DYNAMIC SPECIFICATIONS (fIN(sine wave) = 50kHz, VIN = 2.5VP-P, 420ksps, external fCLK = 7.6MHz, bipolar input mode) Signal-to-Noise Plus Distortion SINAD Total Harmonic Distortion (Including 5th-Order Harmonic) THD Spurious-Free Dynamic Range SFDR 67 70 dB -80 -80 dB dB fIN1 = 49kHz, fIN2 = 52kHz 76 Channel-to-Channel Crosstalk fIN = 175kHz (Note 4) -78 dB Full-Linear Bandwidth SINAD > 68dB 350 kHz Full-Power Bandwidth -3dB rolloff 6 MHz Intermodulation Distortion IMD dB CONVERSION RATE Conversion Time (Note 5) T/H Acquisition Time tCONV 2 External acquisition/internal clock mode 2.5 3.0 3.5 Internal acquisition/internal clock mode 3.2 3.6 4 400 External acquisition or external clock mode Aperture Jitter Duty Cycle 2.1 tACQ Aperture Delay External Clock Frequency External clock mode fCLK 25 External acquisition or external clock mode