M38B53M4-059FP datasheet(222/355 Pages) MITSUBISHI

222 / 355 page

38B5 Group User’s Manual

APPLICATION

2-134

2.6 PWM

2.6.3 PWM application example

(1)

Control of VS tuner

Figure 2.6.5 shows a connection diagram, and Figure 2.6.6 shows the setting of relevant registers.

Fig. 2.6.5 Connection diagram

Outline: • Control of VS tuner by using the 14-bit resolution PWM0 output function

• f(XIN) = 4 MHz

Fig. 2.6.6 Setting of relevant registers

P87/PWM0/FLD39

Filter

ANT

0–32 V

VS tuner

38B5 Group

PWM control register (address 002616)

PWMCON

Select PWM output

Note: The PWM output function has priority even when the

bit corresponded to the P87 pin of the port P8 direction

PWM register (high-order) (address 001416)

Set high-order 8 bits (N) of a 14-bit data to be output

PWMH

Note: Depending on data (N) of the high-order 8 bits, the period (250

! N) of the “H” level during the sub period (64

µs) is

determined.

PWM register (low-order) (address 001516)

Set low-order 6 bits (m) of a 14-bit data to be output

PWML

Note: Depending on data (m) of the low-order 6 bits, the number of

sub period to which the ADD bit is to be added within the

repetitive cycle consisting of 64 sub periods is determined.

When output data is written to the PWM register (low-order),

bit 7 of this register becomes “1”. When completing to transfer

data from the PWM register (low-order) to the PWM latch, bit 7

becomes “0”.

M38B53M4-059FP Datasheet(PDF) 222 Page - Mitsubishi Electric Semiconductor