MAX1266/MAX1268 19-2722 Rev 0 04/03 420ksps, +5V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface General Description Features The MAX1266/MAX1268 low-power, 12-bit analog-to- 12-Bit Resolution, 0.5 LSB Linearity digital converters (ADCs) feature a successive-approxi- Single +5V Operation mation ADC, automatic power-down, fast wake-up (2s), an on-chip clock, +2.5V internal reference, and a Internal +2.5V Reference high-speed 12-bit parallel interface. They operate with Software-Configurable Analog Input Multiplexer a single +5V analog supply. 6-Channel Single Ended/ Power consumption is only 10mW at the maximum sam- 3-Channel Pseudo-Differential (MAX1266) pling rate of 420ksps. Two software-selectable power- 2-Channel Single Ended/ down modes enable the MAX1266/MAX1268 to be shut 1-Channel Pseudo-Differential (MAX1268) down between conversions accessing the parallel interface returns them to normal operation. Powering Software-Configurable Unipolar/Bipolar down between conversions can reduce supply below Analog Inputs 10A at lower sampling rates. Low Current Both devices offer software-configurable analog inputs for 2.8mA (420ksps) unipolar/bipolar and single-ended/pseudo-differential 1.0mA (100ksps) operation. In single-ended mode, the MAX1266 has six 400A (10ksps) input channels and the MAX1268 has two (three input 2A (Shutdown) channels and one input channel, respectively, when in pseudo-differential mode). Internal 6MHz Full-Power Bandwidth Track/Hold Excellent dynamic performance and low power, com- Parallel 12-Bit Interface bined with ease of use and small package size, make Small Footprint these converters ideal for battery-powered and data- acquisition applications or for other circuits with demand- 28-Pin QSOP (MAX1266) ing power-consumption and space requirements. The 24-Pin QSOP (MAX1268) MAX1266 is offered in a 28-pin QSOP package, while the MAX1268 is available in a 24-pin QSOP. For pin-compati- Pin Configurations ble +3V, 12-bit versions, see the MAX1265/MAX1267. TOP VIEW Applications D9 1 24 D10 Industrial Control Systems Data Logging D8 2 23 D11 Energy Management Patient Monitoring D7 3 22 V DD Data-Acquisition Systems Touch Screens D6 4 21 REF D5 5 20 REFADJ MAX1268 D4 6 19 GND Ordering Information D3 7 18 COM INL PART TEMP RANGE PIN-PACKAGE (LSB) D2 8 17 CH0 MAX1266ACEI 0C to +70C 28 QSOP 0.5 D1 9 16 CH1 MAX1266BCEI 0C to +70C 28 QSOP 1 D0 10 15 CS MAX1266AEEI -40C to +85C 28 QSOP 0.5 INT 11 14 CLK MAX1266BEEI -40C to +85C 28 QSOP 1 RD 12 13 WR MAX1268ACEG 0C to +70C 24 QSOP 0.5 MAX1268BCEG 0C to +70C 24 QSOP 1 QSOP MAX1268AEEG -40C to +85C 24 QSOP 0.5 Pin Configurations continued at end of data sheet. MAX1268BEEG -40C to +85C 24 QSOP 1 Typical Operating Circuits appear at end of data sheet. 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.420ksps, +5V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Operating Temperature Ranges DD CH0CH5, COM to GND............................-0.3V to (V + 0.3V) MAX1266 C /MAX1268 C .........................0C to +70C DD REF, REFADJ to GND.................................-0.3V to (V + 0.3V) MAX1266 E /MAX1268 E ......................-40C to +85C DD Digital Inputs to GND ...............................................-0.3V to +6V Storage Temperature Range .............................-65C to +150C Digital Outputs (D0D11, INT) to GND.......-0.3V to (V + 0.3V) Lead Temperature (soldering, 10s) .................................+300C DD Continuous Power Dissipation (T = +70C) A 24-Pin QSOP (derate 9.5mW/C above +70C)..........762mW 28-Pin QSOP (derate 8.0mW/C above +70C)..........667mW 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 = +5V 10%, COM = GND, REFADJ = V , V = +2.5V, 4.7F capacitor at REF pin, f = 7.6MHz (50% duty cycle), DD DD REF CLK T = T to T , unless otherwise noted. Typical values are at T = +25C.) A A MIN MAX PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC ACCURACY (Note 1) Resolution RES 12 Bits MAX126 A 0.5 Relative Accuracy (Note 2) INL LSB MAX126 B 1 Differential Nonlinearity DNL No missing codes overtemperature 1 LSB Offset Error 4 LSB Gain Error (Note 3) 4 LSB Gain Temperature Coefficient 2.0 ppm/C Channel-to-Channel Offset 0.2 LSB Matching DYNAMIC SPECIFICATIONS (f = 50kHz, V = 2.5V , 420ksps, external f = 7.6MHz, bipolar input mode) IN(sine wave) IN P-P CLK Signal-to-Noise Plus Distortion SINAD 67 70 dB Total Harmonic Distortion THD -80 dB (Including 5th-Order Harmonic) Spurious-Free Dynamic Range SFDR -80 dB Intermodulation Distortion IMD f = 49kHz, f = 52kHz 76 dB IN1 IN2 Channel-to-Channel Crosstalk f = 175kHz (Note 4) -78 dB IN Full-Linear Bandwidth SINAD > 68dB 350 kHz Full-Power Bandwidth -3dB rolloff 6 MHz CONVERSION RATE External clock mode 2.1 Conversion Time (Note 5) t External acquisition/internal clock mode 2.5 3.0 3.5 s CONV Internal acquisition/internal clock mode 3.2 3.6 4 T/H Acquisition Time t 400 ns ACQ Aperture Delay External acquisition or external clock mode 25 ns External acquisition or external clock mode <50 Aperture Jitter ps Internal acquisition/internal clock mode <200 External Clock Frequency f 0.1 7.6 MHz CLK Duty Cycle 30 70 % 2 MAX1266/MAX1268