Pin Descriptions

Pin Function

Description

DV

Digital and analog positive supply voltage inputs. Connect both to the same voltage source, but

bypass separately with a 0.1 µF ceramic capacitor in parallel with a 10 µF tantalum capacitor to

ground at each pin.

INT

Active low interrupt output. INT goes low at the end of each conversion, and returns high

following the rising edge of RD.

S/H

Sample/Hold control input. When this pin is forced low (and CS is low), the analog input signal is

sampled and a new conversion is initiated.

RD

Active low read control input. When this RD and CS are low, any data present in the output

registers will be placed onto the data bus.

CS

Active low Chip Select control input. When low, this pin enables the RD and S/H pins.

S0, S1

On the multiple-input devices (ADC10462 and ADC10464), these pins select the analog input

that will be connected to the A/D during the conversion. The input is selected based on the state

of S0 and S1 when S/H makes its High-to-Low transition (See the Timing Diagrams). The

ADC10464 includes both S0 and S1. The ADC10462 includes just S0, and the ADC10461 has

neither.

V

Reference voltage inputs. They may be placed at any voltage between GND and V

must be greater than V

an input voltage equal to (V

V

V

Analog input pins. The ADC10461 has one input (V

V

source should be less than 500

Ω for best accuracy and conversion speed. For accurate

conversions, no input pin (even one that is not selected) should be driven more than 50 mV

above V

GND, AGND,

DGND

Power supply ground pins. The ADC10461 has a single ground pin (GND), and the ADC10462

and ADC10464 have separate analog and digital ground pins (AGND and DGND) for separate

bypassing of the analog and digital supplies. The ground pins should be connected to a stable,

noise-free system ground. For the devices with two ground pins, both pins should be returned to

the same potential.

DB0–DB9

SPEED ADJ

(ADC10462 and ADC10464 only). This pin is normally left unconnected, but by connecting a

resistor between this pin and ground, the conversion time can be reduced. See the Typical

Performance Curves and the table of Electrical Characteristics.

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