MAX1277/MAX1279 19-3365 Rev 1 4/09 1.5Msps, Single-Supply, Low-Power, True- Differential, 12-Bit ADCs with Internal Reference General Description Features The MAX1277/MAX1279 are low-power, high-speed, seri- 1.5Msps Sampling Rate al-output, 12-bit, analog-to-digital converters (ADCs) with Only 22mW (typ) Power Dissipation an internal reference that operates at up to 1.5Msps. These devices feature true-differential inputs, offering bet- Only 1A (max) Shutdown Current ter noise immunity, distortion improvements, and a wider High-Speed, SPI-Compatible, 3-Wire Serial Interface dynamic range over single-ended inputs. A standard 68.5dB S/(N + D) at 525kHz Input Frequency SPI/QSPI/MICROWIRE interface provides the clock necessary for conversion. These devices easily interface Internal True-Differential Track/Hold (T/H) with standard digital signal processor (DSP) synchronous Internal 2.048V Reference serial interfaces. No Pipeline Delays The MAX1277/MAX1279 operate from a single +2.7V to +3.6V supply voltage. The MAX1277/MAX1279 include a Small 12-Pin TQFN Package 2.048V internal reference. The MAX1277 has a unipolar analog input, while the MAX1279 has a bipolar analog input. These devices feature a partial power-down mode and a full power-down mode for use between conver- sions, which lower the supply current to 2mA (typ) and 1A (max), respectively. Also featured is a separate power-supply input (V ), which allows direct interfacing to L +1.8V to V digital logic. The fast conversion speed, DD low-power dissipation, excellent AC performance, and DC accuracy (1 LSB INL) make the MAX1277/MAX1279 ideal for industrial process control, motor control, and Ordering Information base-station applications. PIN- The MAX1277/MAX1279 come in a 12-pin TQFN pack- PART TEMP RANGE INPUT PACKAGE age, and are available in the extended (-40C to +85C) MAX1277AETC-T -40C to +85C 12 TQFN Unipolar temperature range. MAX1277BETC-T -40C to +85C 12 TQFN Unipolar Applications MAX1279AETC-T -40C to +85C 12 TQFN Bipolar MAX1279BETC-T -40C to +85C 12 TQFN Bipolar Data Acquisition Communications Bill Validation Portable Instruments Motor Control Typical Operating Circuit Pin Configuration +1.8V TO V DD +2.7V TO +3.6V TOP VIEW AIN+ N.C. SCLK 0.01F 0.01F 10F 10F 12 11 10 V V DD L AIN- 1 9 CNVST DIFFERENTIAL + DOUT AIN+ INPUT - AIN- REF 2 8 DOUT VOLTAGE MAX1277 C/DSP MAX1277 MAX1279 RGND 3 7 V L MAX1279 CNVST SCLK REF 45 6 RGND GND V N.C. GND 4.7F 0.01F DD TQFN SPI/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 Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.1.5Msps, Single-Supply, Low-Power, True- Differential, 12-Bit ADCs with Internal Reference ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Maximum Current into Any Pin............................................50mA DD V to GND ................-0.3V to the lower of (V + 0.3V) and +6V Continuous Power Dissipation (T = +70C) L DD A Digital Inputs 12-Pin TQFN (derate 16.9mW/C above +70C) ......1349mW to GND .................-0.3V to the lower of (V + 0.3V) and +6V Operating Temperature Range DD Digital Output MAX127 ETC..............................................-40C to +85C to GND....................-0.3V to the lower of (V + 0.3V) and +6V Junction Temperature......................................................+150C L Analog Inputs and Storage Temperature Range .............................-60C to +150C REF to GND..........-0.3V to the lower of (V + 0.3V) and +6V Lead Temperature (soldering, 10s) .................................+300C DD RGND to GND .......................................................-0.3V to +0.3V 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 = +2.7V to +3.6V, V = V , f = 24MHz, 50% duty cycle, T = -40C to +85C, unless otherwise noted. Typical values are DD L DD SCLK A at T = +25C.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC ACCURACY Resolution 12 Bits MAX127 A -1.0 +1.0 Relative Accuracy (Note 1) INL LSB MAX127 B -1.5 +1.5 MAX127 A -1.0 +1.0 Differential Nonlinearity (Note 2) DNL LSB MAX127 B -1.0 +1.5 Offset Error 8.0 LSB Offset-Error Temperature 1 ppm/C Coefficient Gain Error Offset nulled 6.0 LSB Gain Temperature Coefficient 2 ppm/C DYNAMIC SPECIFICATIONS (f = 525kHz sine wave, V = V , unless otherwise noted.) IN IN REF Signal-to-Noise Plus Distortion SINAD 66 68.5 dB Total Harmonic Distortion THD Up to the 5th harmonic -80 -76 dB Spurious-Free Dynamic Range SFDR -83 -76 dB f = 250kHz, f = 300kHz Intermodulation Distortion IMD IN1 IN2 -78 dB Full-Power Bandwidth -3dB point, small-signal method 15 MHz Full-Linear Bandwidth S/(N + D) > 68dB, single ended 1.2 MHz CONVERSION RATE Minimum Conversion Time t (Note 3) 0.667 s CONV Maximum Throughput Rate 1.5 Msps M i nim um Th roug hp ut R ate (N ote 4) 10 ksps Track-and-Hold Acquisition Time t (Note 5) 125 ns ACQ Aperture Delay 5ns Aperture Jitter (Note 6) 30 ps External Clock Frequency f (Note 7) 24 MHz SCLK 2 MAX1277/MAX1279