h8s-2169 Renesas Electronics Corporation., h8s-2169 Datasheet - Page 704

• Manufacturer Part Number: h8s-2169
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 20 A/D Converter
20.4.3
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 20.4 indicates the A/D conversion time.
As indicated in figure 20.5, the A/D conversion time includes t
length of t
time therefore varies within the ranges indicated in table 20.4.
In scan mode, the values given in table 20.4 apply to the first conversion time. In the second and
subsequent conversions the conversion time is fixed at 256 states when CKS = 0 or 128 states
when CKS = 1.
Rev. 3.00 Jan 18, 2006 page 676 of 1044
REJ09B0280-0300
Input Sampling and A/D Conversion Time
D
Address
Write signal
Input sampling
timing
ADF
varies depending on the timing of the write access to ADCSR. The total conversion
Legend:
(1):
(2):
t
t
t
D
SPL
CONV
:
D
after the ADST bit is set to 1, then starts conversion. Figure 20.5 shows the A/D
:
: A/D conversion time
ADCSR write cycle
ADCSR address
A/D conversion start delay
Input sampling time
(1)
(2)
Figure 20.5 A/D Conversion Timing
t
D
t
SPL
t
CONV
D
and the input sampling time. The