LTC1416 UUUPI FU CTIO SA +IN (Pin 1): ±2.5V Positive Analog Input. CONVST (Pin 23): Conversion Start Signal. This active A – low signal starts a conversion on its falling edge. IN (Pin 2): ±2.5V Negative Analog Input. VCS (Pin 24): The Chip Select input must be low for the REF (Pin 3): 2.5V Reference Output. Bypass to AGND with 1µF. ADC to recognize CONVST and RD inputs. CS also sets the shutdown mode when SHDN goes low. CS and REFCOMP (Pin 4): 4.06V Reference Output. Bypass to SHDN low select the quick wake-up nap mode. CS high AGND with 22µF tantalum in parallel with 0.1µF and SHDN low select sleep mode. ceramic, or 22µF ceramic. BUSY (Pin 25): The BUSY output shows the converter AGND (Pin 5): Analog Ground. status. It is low when a conversion is in progress. Data D13 to D6 (Pins 6 to 13): Three-State Data Outputs. is valid on the rising edge of BUSY. DGND (Pin 14): Digital Ground for Internal Logic. Tie to VSS (Pin 26): –5V Negative Supply. Bypass to AGND AGND. with 10µF tantalum in parallel with 0.1µF ceramic, or D5 to D0 (Pins 15 to 20): Three-State Data Outputs. 10µF ceramic. SHDN (Pin 21): Power Shutdown Input. Low selects DVDD (Pin 27): 5V Positive Supply. Tie to Pin 28. shutdown. Shutdown mode selected by CS. CS = 0 for AVDD (Pin 28): 5V Positive Supply. Bypass to AGND nap mode and CS = 1 for sleep mode. with 10µF tantalum in parallel with 0.1µF ceramic, or RD (Pin 22): Read Input. This enables the output 10µF ceramic. drivers when CS is low. UUWFU CTIO AL BLOCK DIAGRA CSAMPLE A + AV IN DD DV C DD SAMPLE A – V IN SS 4k ZEROING SWITCHES VREF 2.5V REF + REF AMP 14-BIT CAPACITIVE DAC COMP – REFCOMP (4.06V) 14 SUCCESSIVE APPROXIMATION • D13 OUTPUT LATCHES • REGISTER • D0 AGND INTERNAL CONTROL LOGIC DGND CLOCK SHDN CONVST RD CS BUSY 1416 BD 6