MAX1297ACEG+

19-1530; Rev 3; 12/02 KIT ATION EVALU LE B A IL A AV 265ksps, +3V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface The MAX1295/MAX1297 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 +2.7V to +3.6V analog supply. Power consumption is only 5.4mW at the maximum sampling rate of 265ksps. Two software-selectable power-down modes enable the MAX1295/MAX1297 to be shut down between conversions; accessing the parallel interface returns them to normal operation. Powering down between conversions can reduce supply current 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 MAX1295 has six input channels and the MAX1297 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 data-acquisition applications or for other circuits with demanding powerconsumption and space requirements. The MAX1295/MAX1297 tri-states INT when CS goes high. Refer to MAX1265/MAX1267 if tri-stating INT is not desired. The MAX1295 is offered in a 28-pin QSOP package, while the MAX1297 comes in a 24-pin QSOP. For pin-compatible +5V, 12-bit versions, refer to the MAX1294/MAX1296 data sheet. Applications Industrial Control Systems Data Logging Energy Management Patient Monitoring Data-Acquisition Systems Touchscreens Features ♦ 12-Bit Resolution, ±0.5 LSB Linearity ♦ +3V Single-Supply Operation ♦ Internal +2.5V Reference ♦ Software-Configurable Analog Input Multiplexer 6-Channel Single-Ended/ 3-Channel Pseudo-Differential (MAX1295) 2-Channel Single-Ended/ 1-Channel Pseudo-Differential (MAX1297) ♦ Software-Configurable Unipolar/Bipolar Analog Inputs ♦ Low Current 1.9mA (265ksps) 1.0mA (100ksps) 400µA (10ksps) 2µA (Shutdown) ♦ Internal 3MHz Full-Power Bandwidth Track/Hold ♦ Parallel 12-Bit Interface ♦ Small Footprint 28-Pin QSOP (MAX1295) 24-Pin QSOP (MAX1297) Pin Configurations TOP VIEW D9 1 28 D10 D8 2 27 D11 D7 3 26 VDD D6 4 25 REF D5 5 D4 6 Ordering Information 24 REFADJ MAX1295 23 GND D3 7 22 COM D2 8 21 CH0 TEMP RANGE PIN-PACKAGE INL (LSB) D1 9 20 CH1 D0 10 19 CH2 MAX1295ACEI 0°C to +70°C 28 QSOP ±0.5 INT 11 18 CH3 MAX1295BCEI 0°C to +70°C 28 QSOP ±1 MAX1295AEEI -40°C to +85°C 28 QSOP ±0.5 MAX1295BEEI -40°C to +85°C 28 QSOP ±1 MAX1297ACEG 0°C to +70°C 24 QSOP ±0.5 MAX1297BCEG 0°C to +70°C 24 QSOP ±1 MAX1297AEEG -40°C to +85°C 24 QSOP ±0.5 MAX1297BEEG -40°C to +85°C 24 QSOP ±1 PART RD 12 17 CH4 WR 13 16 CH5 CLK 14 15 CS 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 MAX1295/MAX1297 General Description MAX1295/MAX1297 265ksps, +3V, 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 8.00mW/°C above +70°C)........667mW Operating Temperature Ranges MAX1295_C_ _ /MAX1297_C_ _ ........................0°C to +70°C MAX1295_E_ _ /MAX1297_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 = +2.7V to +3.6V, COM = GND, REFADJ = VDD, VREF = +2.5V, 4.7µF capacitor at REF pin, fCLK = 4.8MHz (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 12 RES Relative Accuracy (Note 2) INL Differential Nonlinearity DNL Bits MAX129_A ±0.5 MAX129_B ±1 No missing codes over temperature ±1 LSB ±4 LSB Offset Error ±4 Gain Error (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, 265ksps, external fCLK = 4.8MHz, 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 -78 80 dB dB fIN1 = 49kHz, fIN2 = 52kHz 76 dB Channel-to-Channel Crosstalk fIN = 125kHz (Note 4) -78 dB Full-Linear Bandwidth SINAD > 68dB 250 kHz Full-Power Bandwidth -3dB rolloff 3 MHz Intermodulation Distortion IMD CONVERSION RATE Conversion Time (Note 5) Track/Hold Acquisition Time tCONV Aperture Jitter Duty Cycle 2 3.3 External acquisition/internal clock mode 2.5 3.0 3.5 Internal acquisition/internal clock mode 3.2 3.6 4.1 tACQ Aperture Delay External Clock Frequency External clock mode fCLK 625 External acquisition or external clock mode 50 External acquisition or external clock mode