MAX144/MAX145 19-1387 Rev 2 10/05 +2.7V, Low-Power, 2-Channel, 108ksps, Serial 12-Bit ADCs in 8-Pin MAX General Description Features The MAX144/MAX145 low-power, 12-bit analog-to- Single-Supply Operation (+2.7V to +5.25V) digital converters (ADCs) are available in 8-pin MAX Two Single-Ended Channels (MAX144) One and DIP packages. Both devices operate with a single Pseudo-Differential Channel (MAX145) +2.7V to +5.25V supply and feature a 7.4s succes- sive-approximation ADC, automatic power-down, fast Low Power wake-up (2.5s), an on-chip clock, and a high-speed, 0.9mA (108ksps, +3V Supply) 3-wire serial interface. 100A (10ksps, +3V Supply) Power consumption is only 3.2mW (V = +3.6V) at the DD 10A (1ksps, +3V Supply) maximum sampling rate of 108ksps. At slower through- 0.2A (Power-Down Mode) put rates, the automatic shutdown (0.2A) further Internal Track/Hold reduces power consumption. 108ksps Sampling Rate The MAX144 provides 2-channel, single-ended opera- tion and accepts input signals from 0 to V . The REF SPI/QSPI/MICROWIRE-Compatible 3-Wire Serial MAX145 accepts pseudo-differential inputs ranging Interface from 0 to V . An external clock accesses data- REF through the 3-wire serial interface, which is SPI, Space-Saving 8-Pin MAX Package QSPI, and MICROWIRE-compatible. Pin-Compatible 10-Bit Versions Available Excellent dynamic performance and low power, com- bined with ease of use and small package size, make Ordering Information these converters ideal for battery-powered and data- acquisition applications, or for other circuits with TEMP PIN- INL PKG demanding power-consumption and space require- PART RANGE PACKAGE (LSB) CODE ments. For pin-compatible 10-bit ADCs, see the 0C to MAX157 and MAX159 data sheets. MAX144ACUA 8 MAX 0.5 U8-1 +70C Applications 0C to MAX144BCUA 8 MAX 1 U8-1 +70C Battery-Powered Systems Instrumentation 0C to MAX144ACPA 8 Plastic DIP 0.5 P8-1 Portable Data Logging Test Equipment +70C Isolated Data Acquisition Medical Instruments 0C to MAX144BCPA 8 Plastic DIP 1 P8-1 +70C Process-Control Monitoring System Supervision 0C to MAX144BC/D Dice* 1 +70C Pin Configuration -40C to MAX144AEUA 8 MAX 0.5 U8-1 +85C -40C to TOP VIEW MAX144BEUA 8 MAX 1 U8-1 +85C -40C to MAX144AEPA 8 Plastic DIP 0.5 P8-1 V 1 8 SCLK DD +85C -40C to CH0 (CH+) 2 7 DOUT MAX144BEPA 8 Plastic DIP 1 P8-1 +85C MAX144 MAX145 CH1 (CH-) 3 6 CS/SHDN -55C to MAX144AMJA 8 CERDIP** 0.5 J8-2 +125C GND 4 5 REF -55C to MAX144BMJA 8 CERDIP** 1 J8-2 +125C ( ) ARE FOR MAX145 ONLY MAX/DIP *Dice are specified at T = +25C, DC parameters only. A **Contact factory for availability. MAX is a registered trademark of Maxim Integrated Products, Inc. Ordering Information continued at end of data sheet. SPI and 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/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.+2.7V, Low-Power, 2-Channel, 108ksps, Serial 12-Bit ADCs in 8-Pin MAX ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Plastic DIP (derate 9.09mW/C above +70C) ............727mW DD CH0, CH1 (CH+, CH-) to GND ................. -0.3V to (V + 0.3V) CERDIP (derate 8.00mW/C above +70C) ............... 640mW DD REF to GND .............................................. -0.3V to (V + 0.3V) Operating Temperature Ranges (T ) DD A Digital Inputs to GND............................................ -0.3V to +6V MAX144/MAX145 C A .......................................0C to +70C DOUT to GND............................................ -0.3V to (V + 0.3V) MAX144/MAX145 E A..................................-40C to +85C DD DOUT Sink Current ........................................................... 25mA MAX144/MAX145 M A ................................ -55C to +125C Continuous Power Dissipation (T = +70C) Storage Temperature Range .............................-65C to +150C A MAX (derate 4.1mW/C above +70C) .................... 330mW 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 = +2.7V to +5.25V, V = 2.5V, 0.1F capacitor at REF, f = 2.17MHz, 16 clocks/conversion cycle (108ksps), DD REF SCLK CH- = GND for MAX145, 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 MAX14 A 0.5 Relative Accuracy (Note 2) INL LSB MAX14 B 1 Differential Nonlinearity DNL No missing codes over temperature 0.75 LSB Offset Error 3 LSB Gain Error 3 LSB (Note 3) Gain Temperature Coefficient 0.8 ppm/C Channel-to-Channel Offset 0.05 LSB Matching Channel-to-Channel Gain 0.05 LSB Matching DYNAMIC SPECIFICATIONS (f = 10kHz, V = 2.5Vp-p, 108ksps, f = 2.17MHz, CH- = GND for MAX145) IN(sine-wave) IN SCLK Signal-to-Noise Plus SINAD 70 dB Distortion Ratio Total Harmonic Distortion THD -80 dB (including 5th-order harmonic) Spurious-Free Dynamic Range SFDR 80 dB Channel-to-Channel Crosstalk f = 65kHz, V = 2.5Vp-p (Note 4) -85 dB IN IN Small-Signal Bandwidth -3dB rolloff 2.25 MHz Full-Power Bandwidth 1.0 MHz CONVERSION RATE External clock, f = 2.17MHz, SCLK 7.4 16 clocks/conversion cycle Conversion Time (Note 5) t s CONV Internal clock 57 T/H Acquisition Time t 2.5 s ACQ Aperture Delay 25 ns Aperture Jitter <50 ps External clock mode 0.1 2.17 Serial Clock Frequency f MHz SCLK Internal clock mode, for data transfer only05 2 MAX144/MAX145