LTC1410 UUUPI FU CTIO S+ AIN (Pin 1): Positive Analog Input, ±2.5V. SHDN (Pin 21): Power Shutdown Input. A low logic – A level will invoke the Shutdown mode selected by the IN (Pin 2): Negative Analog Input, ±2.5V. NAP/SLP pin. VREF (Pin 3): 2.50V Reference Output. RD (Pin 22): Read Input. This enables the output REFCOMP (Pin 4): 4.06V Reference Bypass Pin. By- drivers when CS is low. pass to AGND with 10µF tantalum in parallel with 0.1µF ceramic. CONVST (Pin 23): Conversion Start Signal. This active low signal starts a conversion on its falling edge. AGND (Pin 5): Analog Ground. CS (Pin 24): The Chip Select input must be low for the D11 to D4 (Pins 6 to 13): Three-State Data Outputs. ADC to recognize CONVST and RD inputs. DGND (Pin 14): Digital Ground for Internal Logic. Tie to BUSY (Pin 25): The BUSY output shows the converter AGND. status. It is low when a conversion is in progress. Data D3 to D0 (Pins 15 to 18): Three-State Data Outputs. valid on the rising edge of BUSY. OGND (Pin 19): Digital Ground for Output Drivers. Tie VSS (Pin 26): –5V Negative Supply. Bypass to AGND to AGND. with 10µF tantalum in parallel 0.1µF ceramic. NAP/SLP (Pin 20): Power Shutdown Mode. Selects the DVDD (Pin 27): 5V Positive Supply. Short to Pin 28. mode invoked by the SHDN pin. Low selects Sleep AV mode and high selects quick wake-up Nap mode. DD (Pin 28): 5V Positive Supply. Bypass to AGND with 10µF tantalum in parallel with 0.1µF ceramic. UUWFU CTIO AL BLOCK DIAGRA CSAMPLE +AIN AVDD CSAMPLE – AIN DVDD 2k ZEROING SWITCHES VREF 2.5V REF VSS + REF AMP 12-BIT CAPACITIVE DAC COMP – REFCOMP (4V) 12 SUCCESSIVE APPROXIMATION • D11 OUTPUT LATCHES • REGISTER • D0 AGND INTERNAL CONTROL LOGIC DGND CLOCK NAP/SLP SHDN CONVST RD CS BUSY LTC1410 • BD 6