h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 640

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 16 A/D Converter
16.4.3
The A/D converter has a built-in sample-and-hold circuit. The A/D converter samples the analog
input at a time t
conversion timing. Table 16.4 indicates the A/D conversion time.
As indicated in figure 16.5, the A/D conversion time includes t
length of t
time therefore varies within the ranges indicated in table 16.4.
In scan mode, the values given in table 16.4 apply to the first conversion time. The values given
in table 16.5 apply to the second and subsequent conversions. In both cases, set bits CKS1 and
CKS0 in ADCR to give a conversion time of at least 10 µs.
Rev. 5.00 Sep 22, 2005 page 614 of 1136
REJ09B0257-0500
Input Sampling and A/D Conversion Time
D
Address
Write signal
Input sampling
timing
ADF
Legend:
(1)
(2)
t
t
t
varies depending on the timing of the write access to ADCSR. The total conversion
D
SPL
CONV
D
after the ADST bit is set to 1, then starts conversion. Figure 16.5 shows the A/D
: ADCSR write cycle
: ADCSR address
: A/D conversion start delay
: Input sampling time
: A/D conversion time
(1)
(2)
Figure 16.5 A/D Conversion Timing
t
D
t
SPL
t
CONV
D
and the input sampling time. The