Datasheet

Rev.6.00 Oct.28.2004 page 702 of 1016
REJ09B0138-0600H
22.1.5 D/A Conversion Characteristics
Table 22-10 lists the D/A conversion characteristics.
Table 22-10 D/A Conversion Characteristics
Conditions: V
CC
= AV
CC
= 5.0 V ± 10%, V
ref
= 4.5 V to AV
CC
, V
SS
= AV
SS
= 0 V,
φ = 10 to 20 MHz, T
a
= –20 to +75°C (regular specifications),
T
a
= –40 to +85°C (wide-range specifications)
Item Min Typ Max Unit Test Conditions
Resolution 8 8 8 bits
Conversion time — — 10 µs 20-pF capacitive load
Absolute accuracy — ±1.0 ±1.5 LSB 2-MΩ resistive load
——±1.0 LSB 4-MΩ resistive load
22.2 Usage Note (Internal Voltage Step Down for the H8S/2398, H8S/2394, H8S/2392, and
H8S/2390)
The H8S/2398, H8S/2394, H8S/2392, or H8S/2390 have a voltage step down circuit that automatically lowers the power
supply voltage, inside the microcomputer, to an adequate level. A capacitor (one 0.47-µF capacitor or two 0.47-µF
capacitors connected in parallel) should be connected between the V
CL
pin (a pin for internal voltage step down circuit)
and V
SS
pin to stabilize the internal voltage. Figure 22-32 shows how to connect the capacitor. Do not connect the V
CC
power-supply to the V
CL
pin. Doing so could permanently damage the LSI. (Connect the V
CC
power-supply to the V
CC
pin,
in the usual way.)
V
CL
V
SS
Do not connect the V
CC
power-supply to the V
CL
pin.
Doing so could permanently damage the LSI.
(Connect the V
CC
power-supply to the other V
CC
pin in the usual way.)
Use a multilayer ceramic capacitor (one 0.47-µF capacitor or two
0.47-µF capacitors connected in parallel) for this circuit, and place it/them
near the V
CL
pin.
An external capacitor to
stabilize the internal voltage
One 0.47-µF capacitor
or two 0.47-µF capacitors
connected in parallel
Figure 22-32 V
CL
Capacitor Connection Method