Modem User Manual

LZT 123 1834 68
Figure 5.17-1 ADC sharing arrangement
ADC sampling frequency and sampling source selection can be set up and controlled
with AT-commands by the user. ADC samples requires up to 5 clock (ADCLK) cycles
to process. The ADC also performs some system-level sampling. These two factors
limit the maximum practical sampling rate to around 20ksps.
Parameter Condition
Min Typ Max Unit
Resolution 10 bit
Coding: Unsigned Magnitude 000 3FF Hex
Differential Nonlinearity –1 1 lsb
Integral Nonlinearity –10 10 lsb
Full-scale Error –3 3 %
Offset Error –14 14 lsb
Conversion Gain* 421 lsb/V
Conversion Intercept* –9 lsb
Low-level Input Voltage ADC output=000h
High-level Input Voltage ADC output=3FFh 2.45 2.59 V
ADC Clock (ADCLK) 260 325 390 kHz
ADC Conversion Time 12 ADCLK
ADC Sample Delay 5 ADCLK