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R01UH0336EJ0102 Rev.1.02
Page 1305 of 1538
Jul 17, 2014
V850E2/PG4-L
Section 23 A/D Converter
23.3.12
Channel Sample and Hold Function
(1)
Channel Sample and Hold Function
The channel sample and hold circuit is shown below.
The channel sample and hold circuit can be used in one-shot conversion mode
for CG0, CG1 and CG2 (no repetition).
The ADCAnSHCTL.ADCAnCSELx bit is used to enable or disable the channel
sample and hold function.
When a hardware or software start trigger occurs, an analog input signal for a
channel for which the sample and hold function is enabled using the
ADCAnSHCTL.ADCAnCSELx bit is held in the channel sample and hold
circuit. Then the scan list conversion is started according to the setting of the
ADCAnCTL1.ADCAnTRMi bit.
Caution
The sampling of channel sample and hold circuit is started by setting
ADCAnCE bit to 1. Input the start trigger after waiting for the channel sample
and hold sampling time (tCAS) after setting ADCAnCE to 1. Because it is not
satisfied the sampling specification for the channel S/H if the start trigger is
input immediately after setting ADCAnCE bit to 1.
H/M
D11-00
SAR/
DAC
Channel S/H circuits
Main parts
of A/D converter
enlargement
ADCAnIx
ADCAnSHCTL.
ADCAnCSELx
MPX
Channel
S/H
“1”
“0”
Channel S/H
Channel S/H
Common
S/H
Channel S/H
ADCAnIx
ADCAnIm