hd66100 Renesas Electronics Corporation., hd66100 Datasheet - Page 374

• Manufacturer Part Number: hd66100
• Description: H8/3867 Series
• Manufacturer: Renesas Electronics Corporation.

14.1
The H8/3867 Series incorporates an internal power supply step-down circuit. Use of this circuit
enables the internal power supply to be fixed at a constant level of approximately 1.5 V,
independently of the voltage of the power supply connected to the external V
the current consumed when an external power supply is used at 1.8 V or above can be held down
to virtually the same low level as when used at approximately 1.5 V. It is, of course, also possible
to use the same level of external power supply voltage and internal power supply voltage without
using the internal power supply step-down circuit.
14.2
Connect the external power supply to the V
µF between CV
effective simply by adding this external circuit.
Notes: 1. In the external circuit interface, the external power supply voltage connected to V
Figure 14.1 Power Supply Connection when Internal Step-Down Circuit Is Used
2. When the internal power supply step-down circuit is used, operating frequency f
3. The LCD power supply and A/D converter analog power supply are not affected by
Overview
When Using the Internal Power Supply Step-Down Circuit
and the GND potential connected to V
input/output levels, the V
is that for the low level.
0.4 MHz to 2 MHz when V
internal step-down processing.
CC
and V
Section 14 Power Supply Circuit
SS
, as shown in figure 14.1. The internal step-down circuit is made
Internal
logic
Step-down circuit
CC
Internal
supply
power
CC
level is the reference for the high level, and the V
= 2.2 V to 5.5 V, and 0.4 MHz to 1 MHz otherwise.
CC
pin, and connect a capacitance of approximately 0.1
V
SS
CC
are the reference levels. For example, for port
V
CV
SS
CC
Stabilization
capacitance
(approx. 0.1 F)
CC
pin. As a result,
SS
osc
level
CC
is
359