M16C62_M Datasheet, PDF (456/615 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

A-D Converter
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
2.7.14 Internal Equivalent Circuit of Analog Input
Figure 2.7.28 shows the internal equivalent circuit of analog input.
Vcc
Parasitic
diode
AN0
Parasitic
diode
Vss
Vcc Vss
ON resistor
approx. 2k Ω Wiring resistor
approx. 0.2k Ω
ON resistor
approx. 0.6k Ω
Analog input voltage
SW1
SW2 ^VIN
AVcc
C = Approx. 3.0pF
AMP
ON resistor,
approx. 5k Ω
Sampling
control signal
i ladder-type
switches
(i = 10)
i ladder-type wiring
resistors
(i = 10)
SW4
SW3
AVss
Chopper-type
amplifier
AN i
SW1
b2 b1 b0
A-D control register 0
VREF
AVss
Resistor
ladder
Reference control
signal
Vref
SW2 Comparison voltage
ON resistor
approx. 0.6k Ω
Comparison reference voltage (Vref) generator
A-D successive conversion
register
ADT/A-D conversion
interrupt request
Control signal
for SW2
Control signal
for SW3
Sampling Comparison
Connect to
Connect to
Connect to
Connect to
SW1 conducts only on the ports selected for analog input.
SW2 and SW3 are open when A-D conversion is not in
progress; their status varies as shown by the waveforms in
the diagrams on the left.
SW4 conducts only when A-D conversion is not in progress.
Warning: Use only as a standard for designing this data.
Mass production may cause some changes in device characteristics.
Figure 2.7.28. Internal equivalent circuit to analog input
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