Rev.1.01
Jan 25, 2005
page 99 of 114
REJ03B0131-0101Z
3804 Group (Spec. H)
NOTES ON USAGE
Handling of Power Source Pins
In order to avoid a latch-up occurrence, connect a capacitor suit-
able for high frequencies as bypass capacitor between power
source pin (VCC pin) and GND pin (VSS pin), and between power
source pin (VCC pin) and analog power source input pin (AVSS
pin). Besides, connect the capacitor to as close as possible. For
bypass capacitor which should not be located too far from the pins
to be connected, a ceramic capacitor of 0.01
F–0.1 F is recom-
mended.
Power Source Voltage
When the power source voltage value of a microcomputer is less
than the value which is indicated as the recommended operating
conditions, the microcomputer does not operate normally and may
perform unstable operation.
In a system where the power source voltage drops slowly when
the power source voltage drops or the power supply is turned off,
reset a microcomputer when the power source voltage is less than
the recommended operating conditions and design a system not
to cause errors to the system by this unstable operation.
Flash Memory Version
The CNVss pin determines the flash memory mode. To improve
the noise reduction, connect a track between CNVss pin and Vss
pin or Vcc pin with 1 to 10 k
resistance. The mask ROM version
track of CNVss pin has no operational interference even if it is
connected to Vss pin or Vcc pin via a resistor.
Electric Characteristic Differences Between
Mask ROM and Flash Memory Version MCUs
There are differences in electric characteristics, operation margin,
noise immunity, and noise radiation between Mask ROM and
Flash Memory version MCUs due to the difference in the manufac-
turing processes, built-in ROM, and layout pattern etc.When
manufacturing an application system with the Flash Memory ver-
sion and then switching to use of the Mask ROM version, please
conduct evaluations equivalent to the system evaluations con-
ducted for the flash memory version.
DATA REQUIRED FOR MASK ORDERS
The following are necessary when ordering a mask ROM produc-
tion:
1.Mask ROM Confirmation Form
2.Mark Specification Form
3.Data to be written to ROM, in EPROM form (three identical cop-
ies)
For the mask ROM confirmation and the mark specifications,
refer to the
“
Renesas Technology Corp.” Homepage
(http://www.renesas.com/en/rom).