LTC1400 Complete SO-8, 12-Bit, 400ksps ADC with Shutdown UFEATURESDESCRIPTIO ■ Complete 12-Bit ADC in SO-8 The LTC®1400 is a complete 400ksps, 12-bit A/D converter ■ Single Supply 5V or ±5V Operation which draws only 75mW from 5V or ±5V supplies. This ■ Sample Rate: 400ksps easy-to-use device comes complete with a 200ns sample- ■ Power Dissipation: 75mW (Typ) and-hold and a precision reference. Unipolar and bipolar ■ 72dB S/(N + D) and –80dB THD at Nyquist conversion modes add to the flexibility of the ADC. The ■ No Missing Codes over Temperature LTC1400 has two power saving modes: Nap and Sleep. ■ Nap Mode with Instant Wake-Up: 6mW In Nap mode, it consumes only 6mW of power and can ■ Sleep Mode: 30μW wake up and convert immediately. In the Sleep mode, it ■ High Impedance Analog Input consumes 30μW of power typically. Upon power-up from ■ Input Range (1mV/LSB): 0V to 4.096V or ±2.048V Sleep mode, a reference ready (REFRDY) signal is available ■ Internal Reference Can Be Overdriven Externally in the serial data word to indicate that the reference has ■ 3-Wire Interface to DSPs and Processors (SPI and settled and the chip is ready to convert. MICROWIRETM Compatible) The LTC1400 converts 0V to 4.096V unipolar inputs from U a single 5V supply and ±2.048V bipolar inputs from ±5V APPLICATIO S supplies. Maximum DC specs include ±1LSB INL, ±1LSB ■ High Speed Data Acquisition DNL and 45ppm/°C drift over temperature. Guaranteed AC ■ Digital Signal Processing performance includes 70dB S/(N + D) and –76dB THD at ■ Multiplexed Data Acquisition Systems an input frequency of 100kHz, over temperature. ■ Audio and Telecom Processing The 3-wire serial port allows compact and efficient data ■ Digital Radio transfer to a wide range of microprocessors, microcon- ■ Spectrum Analysis trollers and DSPs. ■ Low Power and Battery-Operated Systems ■ Handheld or Portable Instruments , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. UTYPICAL APPLICATIOSingle 5V Supply, 400kHz, 12-Bit Sampling A/D ConverterPower Consumption vs Sample Rate 100 5V NORMAL CONVERSION 10 VCC VSS + NAP MODE BETWEEN CONVERSION 10µF 0.1µF 1 MPU LTC1400 ANALOG INPUT SLEEP AND NAP MODE AIN CONV P1.4 (0V TO 4.096V) 0.1 BETWEEN CONVERSION 2.42V REF V SLEEP MODE BETWEEN OUT REF CLK P1.3 + SUPPLY CURRENT (mA) CONVERSION 10µF 0.1µF GND D 0.01 OUT P1.2 SERIAL DATA LINK 6.4MHz CLOCK 1400 TA01 0.0010.01 0.1 1 10 100 1k 10k 100k 1M SAMPLE RATE (Hz) 1400 TA02 1400fa 1