MAX1280/MAX1281 19-1684 Rev 2 10/10 400ksps/300ksps, Single-Supply, Low-Power, 8-Channel, Serial 12-Bit ADCs with Internal Reference General Description Features The MAX1280/MAX1281 12-bit ADCs combine an 8-chan- 8-Channel Single-Ended or 4-Channel nel analog-input multiplexer, high-bandwidth track/hold, Pseudo-Differential Inputs and serial interface with high conversion speed and low Internal Multiplexer and Track/Hold power consumption. The MAX1280 operates from a single +4.5V to +5.5V supply the MAX1281 operates from a sin- Single-Supply Operation gle +2.7V to +3.6V supply. Both devices analog inputs +4.5V to +5.5V (MAX1280) are software configurable for unipolar/bipolar and single- +2.7V to +3.6V (MAX1281) ended/pseudo-differential operation. Internal +2.5V Reference The 4-wire serial interface connects directly to 400ksps Sampling Rate (MAX1280) SPI/QSPI/MICROWIRE devices without external logic. A serial strobe output allows direct connection to Low Power 2.5mA (400ksps) TMS320-family digital signal processors. The MAX1280/ 1.3mA (Reduced-Power Mode) MAX1281 use an external serial-interface clock to per- 0.9mA (Fast Power-Down Mode) form successive-approximation analog-to-digital con- 2A (Full Power-Down) versions. Both parts feature an internal +2.5V reference and a reference-buffer amplifier with a 1.5% voltage- SPI/QSPI/MICROWIRE/TMS320-Compatible adjustment range. An external reference with a 1V to 4-Wire Serial Interface V range may also be used. DD1 Software-Configurable Unipolar or Bipolar Inputs The MAX1280/MAX1281 provide a hard-wired SHDN 20-Pin TSSOP Package pin and four software-selectable power modes (normal operation, reduced power, fast power-down, and full power-down). These devices can be programmed to Ordering Information automatically shut down at the end of a conversion or to operate with reduced power. When using the power- TEMP PIN- INL PART down modes, accessing the serial interface automatical- RANGE PACKAGE (LSB) ly powers up the devices, and the quick turn-on time MAX1280BCUP+ 0C to +70C 20 TSSOP 1 allows them to be powered down between all conver- MAX1280BEUP+ -40C to +85C 20 TSSOP 1 sions. This technique can cut supply current to under 100A at reduced sampling rates. MAX1281BCUP+ 0C to +70C 20 TSSOP 1 MAX1281BEUP+ -40C to +85C 20 TSSOP 1 The MAX1280/MAX1281 are available in 20-pin TSSOP +Denotes a lead(Pb)-free/RoHS-compliant package. packages. These devices are higher-speed versions of the MAX146/MAX147 (for more information, see the respective data sheet). Pin Configuration Applications TOP VIEW + Portable Data Logging CH0 1 20 V DD1 Data Acquisition CH1 2 19 V DD2 Medical Instruments SCLK CH2 3 18 MAX1280 CH3 CS Battery-Powered Instruments 4 17 MAX1281 5 CH4 16 DIN Pen Digitizers CH5 6 15 SSTRB Process Control CH6 7 14 DOUT CH7 8 13 GND REFADJ COM 9 12 SHDN 10 11 REF SPI and QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp. TSSOP 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. EVALUATION KIT AVAILABLE400ksps/300ksps, Single-Supply, Low-Power, 8-Channel, Serial 12-Bit ADCs with Internal Reference ABSOLUTE MAXIMUM RATINGS V to GND............................................................ -0.3V to +6V 20-Pin TSSOP (derate 7.0mW/C above +70C) .........559mW DD V to V ........................................................ -0.3V to +0.3V Operating Temperature Ranges DD1 DD2 CH0CH7, COM to GND.......................... -0.3V to (V + 0.3V) MAX128 BCUP.................................................. 0C to +70C DD1 REF, REFADJ to GND .............................. -0.3V to (V + 0.3V) MAX128 BEUP ............................................... -40C to +85C DD1 Digital Inputs to GND .............................................. -0.3V to +6V Storage Temperature Range ............................ -60C to +150C Digital Outputs to GND ............................ -0.3V to (V + 0.3V) Lead Temperature (soldering, 10s) ................................ +300C DD2 Digital Output Sink Current .................................................25mA Soldering Temperature (reflow) ...................................... +260C Continuous Power Dissipation (T = +70C) A 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 CHARACTERISTICSMAX1280ELECTRICAL CHARACTERISTICSMAX1280 (V(V = V= V = +4.5V to +5.5V, COM = GND, f= +4.5V to +5.5V, COM = GND, f = 6.4MHz, 50% duty cycle, 16 clocks/conversion cycle (400ksps), external= 6.4MHz, 50% duty cycle, 16 clocks/conversion cycle (400ksps), external DD1DD1 DD2DD2 SCLKSCLK +2.5V at REF, REFADJ = V+2.5V at REF, REFADJ = V , T, T = T= T to Tto T , unless otherwise noted. Typical values are at T, unless otherwise noted. Typical values are at T = +25C.)= +25C.) DD1DD1 AA MINMIN MAXMAX AA PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC ACCURACY (Note 1) Resolution 12 Bits 1.0 Relative Accuracy (Note 2) INL LSB Differential Nonlinearity DNL No missing codes over temperature 1.0 LSB Offset Error 6.0 LSB Gain Error (Note 3) 7.0 LSB Gain-Error Temperature 0.8 ppm/C Coefficient Channel-to-Channel Offset-Error 0.1 LSB Matching DYNAMIC SPECIFICATIONS (100kHz sine-wave input, 2.5Vp-p, 400ksps, 6.4MHz clock, bipolar input mode) Signal-to-Noise plus Distortion SINAD 70 dB Ratio Total Harmonic Distortion THD Up to the 5th harmonic -81 dB Spurious-Free Dynamic Range SFDR 80 dB Intermodulation Distortion IMD f = 99kHz, f = 102kHz 76 dB IN1 IN2 Channel-to-Channel Crosstalk -78 f = 200kHz, V = 2.5Vp-p dB IN IN (Note 4) Full-Power Bandwidth -3dB point 6 MHz Full-Linear Bandwidth SINAD > 68dB 350 kHz CONVERSION RATE Conversion Time (Note 5) t 2.5 s CONV Track/Hold Acquisition Time t 468 ns ACQ Aperture Delay 10 ns Aperture Jitter <50 ps Serial Clock Frequency f 0.5 6.4 MHz SCLK Duty Cycle 40 60 % 2 MAX1280/MAX1281