M37221M4H/M6H/M8H/MAH–XXXSP/FP M37221EASP/FP
Set “2816” to DA-L register.
Set “2C16” to DA-H register.
b7 b6 b5 b4 b3 b2 b1 b0
b7 b6 b5 b4 b3 b2 b1 b0
[DA-H
register]
[DA-L register]
DH
0
DL
0
1
0
1
1
0
0
1
0
1
0
0
0
At writing of DA-L
b0
At writing of DA-L
b13
b6 b5
[DA latch]
0
0
1
0
1
1
0
0
1
0
1
0
0
0
These bits decide HIGH level area
of fundamental waveform.
These bits decide smaller interval “tm” in which HIGH leval
area is [HIGH level area of fundamental waveform + τ ].
Minimum
resolution bit
width 0.25
HIGH level area of
fundamental waveform
High-order 8-bit
value of DA latch
=
✕
µs
Fundamental
waveform
Waveform of smaller interval “tm” specified by low-order 6 bits
0.25 µs✕44
0.25 µs✕45
0.25 µs
14-bit
PWM output
14-bit
PWM output
…
…
2C 2B 2A
03 02 01 00
D6 D5 D4 D3
2C 2B 2A
03 02 01 00
…
D6 D5 D4 D3 02 01 00
8-bit
counter
8-bit
counter
…
…
…
FF FE FD
02 01 00
FF FE FD
Fundamental waveform of smaller interval
“tm” which is not specified by low-order 6
bits is not changed.
0.25 µs✕44
τ = 0.25 µs
14-bit PWM output
t
0
t
1
t
2
t
3
t
4
t
5
t
59
t
60
t
61
t
62
t63
Low-order 6-bit output of
DA latch
Repeat period
T = 4096 µs
Fig. 8.7.3 14-bit PWM Timing (f(XIN) = 8 MHz)
Rev.1.00 Oct 01, 2002 page 47 of 110
REJ03B0134-0100Z
RENESAS [ RENESAS TECHNOLOGY CORP ]
