MAX1291/MAX1293 19-1532 Rev 3 12/02 250ksps, +3V, 8-/4-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface General Description Features The MAX1291/MAX1293 low-power, 12-bit analog-to-dig- 12-Bit Resolution, 0.5 LSB Linearity ital converters (ADCs) feature a successive-approxima- +3V Single Operation tion ADC, automatic power-down, fast wake-up (2s), an on-chip clock, +2.5V internal reference, and a high- User-Adjustable Logic Level (+1.8V to +3.6V) speed, byte-wide parallel interface. They operate with a Internal +2.5V Reference single +3V analog supply and feature a V pin that LOGIC allows them to interface directly with a +1.8V to +5.5V Software-Configurable, Analog Input Multiplexer digital supply. 8-Channel Single-Ended/ Power consumption is only 5.7mW (V = V ) at the DD LOGIC 4-Channel Pseudo-Differential (MAX1291) maximum sampling rate of 250ksps. Two software-selec- 4-Channel Single-Ended/ table power-down modes enable the MAX1291/ 2-Channel Pseudo-Differential (MAX1293) MAX1293 to be shut down between conversions Software-Configurable, Unipolar/Bipolar Inputs accessing the parallel interface returns them to normal operation. Powering down between conversions can cut Low Power: 1.9mA (250ksps) supply current to under 10A at reduced sampling rates. 1.0mA (100ksps) Both devices offer software-configurable analog inputs 400A (10ksps) for unipolar/bipolar and single-ended/pseudo-differen- 2A (Shutdown) tial operation. In single-ended mode, the MAX1291 has Internal 3MHz Full-Power Bandwidth Track/Hold eight input channels and the MAX1293 has four input channels (four and two input channels, respectively, Byte-Wide Parallel (8 + 4) Interface when in pseudo-differential mode). Small Footprint: 28-Pin QSOP (MAX1291) Excellent dynamic performance and low power, com- 24-Pin QSOP (MAX1293) bined with ease of use and small package size, make these converters ideal for battery-powered and data- acquisition applications or for other circuits with demand- Pin Configurations ing power consumption and space requirements. The MAX1291/MAX1293 tri-states INT when CS goes TOP VIEW high. Refer to MAX1261/MAX1263 if tri-stating INT is not HBEN 1 28 V LOGIC desired. D7 2 27 V DD The MAX1291 is available in a 28-pin QSOP package, while the MAX1293 is available in a 24-pin QSOP. For D6 3 26 REF pin-compatible +5V, 12-bit versions, refer to the D5 4 25 REFADJ MAX1290/MAX1292 data sheet. D4 5 24 GND MAX1291 D3/D11 6 23 COM Applications D2/D10 7 22 CH0 Industrial Control Systems Data Logging D1/D9 8 21 CH1 Energy Management Patient Monitoring D0/D8 9 20 CH2 Data-Acquisition Systems Touch Screens INT 10 19 CH3 Ordering Information RD 11 18 CH4 INL WR 12 17 CH5 PART TEMP RANGE PIN-PACKAGE (LSB) CLK 13 16 CH6 MAX1291ACEI 0C to +70C 28 QSOP 0.5 CS 14 15 CH7 0C to +70C MAX1291BCEI 28 QSOP 1 -40C to +85C MAX1291AEEI 28 QSOP 0.5 QSOP -40C to +85C Pin Configurations continued at end of data sheet. MAX1291BEEI 28 QSOP 1 Ordering Information continued at end of data sheet. 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. EVALUATION KIT AVAILABLE250ksps, +3V, 8-/4-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) DD A V to GND.........................................................-0.3V to +6V 24-Pin QSOP (derate 9.5mW/C above +70C) ...........762mW LOGIC CH0CH7, COM to GND............................-0.3V to (V + 0.3V) 28-Pin QSOP (derate 8.00mW/C above +70C) .........667mW DD REF, REFADJ to GND ................................-0.3V to (V + 0.3V) Operating Temperature Ranges DD Digital Inputs to GND ...............................................-0.3V to +6V MAX1291 C /MAX1293 C ..............................0C to +70C Digital Outputs (D0D11, INT) to GND...-0.3V to (V + 0.3V) MAX1291 E /MAX1293 E ...........................-40C to +85C LOGIC Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C 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 = V = +2.7V to +3.6V, COM = GND, REFADJ = V , V = +2.5V, 4.7F capacitor at REF pin, f = 4.8MHz (50% duty DD LOGIC DD REF CLK cycle) T = T to T , unless otherwise noted. Typical values are at T = +25C.) A MIN MAX A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC ACCURACY (Note 1) Resolution RES 12 Bits MAX129 A 0.5 Relative Accuracy (Note 2) INL LSB MAX129 B 1 Differential Nonlinearity DNL No missing codes over temperature 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 , 250ksps, external f = 4.8MHz, bipolar input mode) IN(sine wave) IN P-P CLK Signal-to-Noise Plus Distortion SINAD 67 70 dB Total Harmonic Distortion THD -78 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 = 125kHz, V = 2.5V (Note 4) -78 dB P-P IN IN Full-Linear Bandwidth SINAD > 68dB 250 kHz Full-Power Bandwidth -3dB rolloff 3 MHz CONVERSION RATE External clock mode 3.3 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 4.1 Track/Hold Acquisition Time t 625 ns ACQ Aperture Delay External acquisition or external clock mode 50 ns External acquisition or external clock mode <50 Aperture Jitter ps Internal acquisition/internal clock mode <200 External Clock Frequency f 0.1 4.8 MHz CLK Duty Cycle 30 70 % 2 MAX1291/MAX1293