LTC1857/LTC1858/LTC1859 8-Channel, 12-/14-/16-Bit, 100ksps SoftSpan A/D Converters with Shutdown FEATURESDESCRIPTION n Sample Rate: 100ksps The LTC®1857/LTC1858/LTC1859 are 8-channel, low n 8-Channel Multiplexer with ±25V Protection power, 12-/14-/16-bit, 100ksps, analog-to-digital convert- n Single 5V Supply ers (ADCs). These SoftSpan™ ADCs can be software- n Software-Programmable Input Ranges: programmed for 0V to 5V, 0V to 10V, ±5V or ±10V input n 0V to 5V, 0V to 10V, ±5V or ±10V spans and operate from a single 5V supply. The 8-channel n Single-Ended or Differential multiplexer can be programmed for single-ended inputs n ±3LSB INL for the LTC1859, ±1.5LSB INL for the or pairs of differential inputs or combinations of both. In LTC1858, ±1LSB INL for the LTC1857 addition, all channels are fault protected to ±25V. A fault n Power Dissipation: 40mW (Typ) condition on any channel will not affect the conversion n SPI/MICROWIRE™ Compatible Serial I/O result of the selected channel. n Power Shutdown: Nap and Sleep An onboard high performance sample-and-hold and pre- n Signal-to-Noise Ratio: 87dB (Typ) for the LTC1859 cision reference minimize external components. The low n Operates with Internal or External Reference 40mW power dissipation is made even more attractive with n Internal Synchronized Clock two user selectable power shutdown modes. DC specifica- n 28-Pin SSOP Package tions include ±3LSB INL for the LTC1859, ±1.5LSB INL for the LTC1858 and ±1LSB for the LTC1857. APPLICATIONS The internal clock is trimmed for 5µs maximum conversion n Industrial Process Control time and the sampling rate is guaranteed at 100ksps. A n Multiplexed Data Acquisition Systems separate convert start input and data ready signal (BUSY) n High Speed Data Acquisition for PCs ease connections to FIFOs, DSPs and microprocessors. n Digital Signal Processing L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. SoftSpan is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION100kHz, 12-Bit/14-Bit/16-Bit Sampling ADCLTC1859 Typical INL Curve 2.0 COM CONVST CH0 RD LTC1857/ 1.5 CH1 LTC1858/ SCK µP CH2 LTC1859 SDI CONTROL 1.0 SOFTWARE-PROGRAMMABLE CH3 DGND LINES SINGLE-ENDED OR 0.5 CH4 SDO DIFFERENTIAL INPUTS (0V TO 5V, 0V TO 10V, CH5 BUSY 0 ±5V OR ±10V) CH6 OVDD 3V TO 5V INL (LSB) –0.5 CH7 DVDD 5V MUXOUT+ AVDD 5V –1.0 MUXOUT– AGND3 10µF 10µF 10µF ADC+ AGND2 –1.5 ADC– REFCOMP –2.0 AGND1 VREF 2.5V –32768 –16384 0 16384 32767 1µF 10µF CODE 1859 TA02 185789fb For more information www.linear.com/LTC1857 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Converter and Multplexer Characteristics Analog Input Dynamic Accuracy Internal Reference Characteristics Digital Inputs and Digital Outputs Power Requirements Timing Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Test Circuits Timing Diagrams Operation Applications Information Package Description Revision History Typical Application Related Parts