LTC1606 UUUPI FU CTIO SVIN (Pin 1): Analog Input. Connect through a 200Ω being the LSB. With BYTE high, the upper eight bits and resistor to the analog input. Full-scale input range is the lower eight bits will be switched. The MSB is output ±10V. on Pin 15 and bit 8 is output on Pin 22. Bit 7 is output on Pin 6 and the LSB is output on Pin 13. AGND1 (Pin 2): Analog Ground. Tie to analog ground plane. R/C (Pin 24): Read/Convert Input. With CS low, a falling edge on R/C puts the internal sample-and-hold into the REF (Pin 3): 2.5V Reference Output. Bypass with 2.2µF hold state and starts a conversion. With CS low, a rising tantalum capacitor. Can be driven with an external edge on R/C enables the output data bits. reference. CS (Pin 25): Chip Select. Internally OR’d with R/C. With CAP (Pin 4): Reference Buffer Output. Bypass with 10µF R/C low, a falling edge on CS will initiate a conversion. tantalum capacitor. The capacitor output voltage is 4.096V With R/C high, a falling edge on CS will enable the output when REF = 2.5V. data. AGND2 (Pin 5): Analog Ground. Tie to analog ground BUSY (Pin 26): Output Shows Converter Status. It is low plane. when a conversion is in progress. Data valid on the rising D15 to D8 (Pins 6 to 13): Three-State Data Outputs. edge of BUSY. CS or R/C must be high when BUSY rises Hi-Z state when CS is high or when R/C is low. or another conversion will start without time for signal DGND (Pin 14): Digital Ground. acquisition. D7 to D0 (Pins 15 to 22): Three-State Data Outputs. VANA (Pin 27): 5V Analog Supply. Bypass to ground with Hi-Z state when CS is high or when R/C is low. a 0.1µF ceramic and a 10µF tantalum capacitor. BYTE (Pin 23): Byte Select. With BYTE low, data will be VDIG (Pin 28): 5V Digital Supply. Connect directly to output with Pin 6 (D15) being the MSB and Pin 22 (D0) Pin 27. UUWFU CTIO AL BLOCK DIAGRA CSAMPLE 7.35k VIN V 9k 2.5k ANA CSAMPLE VDIG ZEROING SWITCHES 4k REF 2.5V REF + REF BUF 16-BIT CAPACITIVE DAC COMP 1.64x – CAP (4.096V) 16 SUCCESSIVE APPROXIMATION • D15 OUTPUT LATCHES • REGISTER • D0 AGND1 AGND2 INTERNAL CONTROL LOGIC DGND CLOCK 1606 BD CS R/C BYTE BUSY 1606fa 7