HD6432160 RENESAS [Renesas Technology Corp], HD6432160 Datasheet - Page 608

• Manufacturer Part Number: HD6432160
• Description: Hitachi 16-Bit Single-Chip Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

21.4.3
The A/D converter has a built-in sample-and-hold circuit. The A/D converter samples the analog
input when the A/D conversion start delay time (t
1, then starts A/D conversion. Figure 21.3 shows the A/D conversion timing. Table 21.3 indicates
the A/D conversion time.
As indicated in figure 21.3, the A/D conversion time (t
(t
conversion time therefore varies within the ranges indicated in table 21.3.
In scan mode, the values given in table 21.3 apply to the first conversion time. In the second and
subsequent conversions, the conversion time is 256 state (fixed) when CKS = 0 and 128 states
(fixed) when CKS = 1.
Rev. 2.0, 08/02, page 568 of 788
SPL
). The length of t
Input Sampling and A/D Conversion Time
Address
Write signal
Input sampling
timing
ADF
ø
Legend
(1)
(2)
t
t
t
D
SPL
CONV
D
: ADCSR write cycle
: ADCSR address
: A/D conversion start delay
: Input sampling time
: A/D conversion time
varies depending on the timing of the write access to ADCSR. The total
(1)
(2)
Figure 21.3 A/D Conversion Timing
t D
t SPL
D
) passes after the ADST bit in ADCSR is set to
t CONV
CONV
) includes t
D
and the input sampling time