M30620FCAFP datasheet(178/615 Pages) RENESAS

178 / 615 page

Mitsubishi microcomputers

M16C / 62A Group

SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

D-A Converter

1-159

D-A Converter

This is an 8-bit, R-2R type D-A converter. The microcomputer contains two independent D-A converters of

this type.

D-A conversion is performed when a value is written to the corresponding D-A register. Bits 0 and 1 (D-A

output enable bits) of the D-A control register decide if the result of conversion is to be output. Do not set the

target port to output mode if D-A conversion is to be performed. When the D-A output is enabled, the pull-

up function of the corresponding port is automatically disabled.

Output analog voltage (V) is determined by a set value (n : decimal) in the D-A register.

V = VREF X n/ 256 (n = 0 to 255)

VREF : reference voltage

Table 1.18.1 lists the performance of the D-A converter. Figure 1.18.1 shows the block diagram of the D-A

converter. Figure 1.18.2 shows the D-A control register. Figure 1.18.3 shows the D-A converter equivalent

circuit.

Item

Performance

Conversion method

R-2R method

Resolution

8 bits

Analog output pin

2 channels

Table 1.18.1. Performance of D-A converter

P93/DA0

P94/DA1

Data bus low-order bits

D-A register 0 (8)

R-2R resistor ladder

D-A0 output enable bit

D-A register 1 (8)

R-2R resistor ladder

D-A1 output enable bit

(Address 03D816)

(Address 03DA16)

Figure 1.18.1. Block diagram of D-A converter

M30620FCAFP Datasheet(PDF) 178 Page - Renesas Technology Corp