A.1.1 A/D Converter

Table A-2shows some of the important A/D converter specifications. For more details, refer to the ADC7870 data sheet.

Table A-2.

A/D Converter Specifications

 

 

 

 

 

 

Parameter

 

Test Conditions

Typ

Max

 

 

 

 

 

Analog Input Characteristics

 

 

 

 

Input Capacitance

 

 

4 – 9.7 pF

 

Input Impedance

 

 

 

 

Common-Mode

 

 

6 MΩ

 

Differential Mode

 

 

7 MΩ

 

 

 

 

 

 

Static Accuracy

 

 

 

 

Resolution

 

 

 

 

Single-Ended Mode

 

 

11 bits

 

Differential Mode

 

 

12 bits

 

Integral Linearity

 

 

±1 LSB

±2.5 LSB

Differential Linearity

 

 

±0.5 LSB

 

 

 

 

 

 

Dynamic Characteristics

 

 

 

 

Throughput Rate

 

 

52 ksamples/s

 

 

 

 

 

 

Voltage Reference

 

 

 

 

Accuracy

 

Vref = 2.048 V and 2.5 V

±0.05%

±0.25%

Buffer Amp Source Current

 

 

20 µA

 

Buffer Amp Sink Current

 

 

20 mA

 

Short-Circuit Current

 

 

20 mA

 

 

 

 

 

 

82

RabbitCore RCM4000

Page 88
Image 88
Digi RCM4000 user manual 1 A/D Converter, Table A-2 Converter Specifications, Parameter Test Conditions