HD64336901G Renesas Technology, HD64336901G Datasheet - Page 307

• Manufacturer Part Number: HD64336901G
• Description: (HD64xxx Series) 16-BIT MICROCONTROLLER
• Manufacturer: Renesas Technology

This LSI 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 3.0 V, independently of the
voltage of the power supply connected to the external V
when an external power supply is used at 3.0 V or above can be held down to virtually the same
low level as when used at approximately 3.0 V. If the external power supply is 3.0 V or below, the
internal voltage will be practically the same as the external voltage. 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.
18.1
Connect the external power supply to the V
µF between V
simply by adding this external circuit. In the external circuit interface, the external power supply
voltage connected to V
example, for port input/output levels, the V
level is that for the low level. The A/D converter analog power supply is not affected by the
internal step-down circuit.
PSCKT00A_000020020200
Figure 18.1 Power Supply Connection when Internal Step-Down Circuit is Used
When Using Internal Power Supply Step-Down Circuit
CL
and V
Section 18 Power Supply Circuit
SS
CC
, as shown in figure 18.1. The internal step-down circuit is made effective
and the GND potential connected to V
Internal
logic
Step-down circuit
Internal
power
supply
CC
CC
V
level is the reference for the high level, and the V
pin, and connect a capacitance of approximately 0.1
CC
V
V
SS
CL
Stabilization
capacitance
(approx. 0.1 F)
CC
pin. As a result, the current consumed
V
CC
= 3.0 to 5.5 V
SS
Rev. 1.00, 11/03, page 279 of 376
are the reference levels. For
SS