M37544G2AGP#U0 Renesas Electronics America, M37544G2AGP#U0 Datasheet - Page 44

• Manufacturer Part Number: M37544G2AGP#U0
• Description: IC 740 MCU OTP 8K 32LQFP
• Manufacturer: Renesas Electronics America
• Series: 740/38000r

Specifications of M37544G2AGP#U0

• Core Processor: 740
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SIO, UART/USART
• Peripherals: WDT
• Number Of I /o: 25
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: QzROM
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 6x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 32-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Rev.1.04
REJ03B0012-0104Z
Fig. 54 Bypass capacitor across the V
7544 Group
(5) Wiring to V
Connect an approximately 5 k
possible in series and also to the Vss pin. When not connecting
the resistor, make the length of wiring between the V
the Vss pin the shortest possible.
Note: Even when a circuit which included an approximately 5 k
<Reason>
The V
for the built-in PROM. When programming in the built-in PROM,
the impedance of the V
writing flow into the PROM. Because of this, noise can enter eas-
ily. If noise enters the V
are read from the built-in PROM, which may cause a program run-
away.
Fig. 53 Wiring for the V
2. Connection of bypass capacitor across V
Connect an approximately 0.1 F bypass capacitor across the V
line and the V
• Connect a bypass capacitor across the V
• Connect a bypass capacitor across the V
• Use lines with a larger diameter than other signal lines for V
• Connect the power source wiring via a bypass capacitor to the
at equal length.
with the shortest possible wiring.
line and V
V
SS
resistor is used in the Mask ROM version, the microcom-
puter operates correctly.
PP
pin and the V
pin of the One Time PROM is the power source input pin
CC
2004.06.08
N.G.
CC
PP
CNV
line.
V
V
line as follows:
pin of One Time PROM version
SS
CC
CC
SS
/V
pin.
PP
V
PP
SS
PP
PP
pin is low to allow the electric current for
pin, abnormal instruction codes or data
page 42 of 66
pin of the One Time PROM
resistor to the V
About 5k
distance
shortest
SS
SS
SS
SS
line and the V
pin and the V
pin and the V
line and V
PP
O.K.
V
V
pin the shortest
CC
SS
PP
CC
pin and
CC
CC
CC
line
line
pin
pin
SS
SS
Fig. 55 Analog signal line and a resistor and a capacitor
3. Wiring to analog input pins
• Connect an approximately 100
• Connect an approximately 1000 pF capacitor across the Vss pin
<Reason>
Signals which is input in an analog input pin (such as an A/D con-
verter/comparator input pin) are usually output signals from
sensor. The sensor which detects a change of event is installed far
from the printed circuit board with a microcomputer, the wiring to
an analog input pin is longer necessarily. This long wiring func-
tions as an antenna which feeds noise into the microcomputer,
which causes noise to an analog input pin.
• The analog input pin is connected to the capacitor of a voltage
signal line which is connected to an analog input pin in series.
Besides, connect the resistor to the microcomputer as close as
possible.
and the analog input pin. Besides, connect the capacitor to the
Vss pin as close as possible. Also, connect the capacitor across
the analog input pin and the Vss pin at equal length.
comparator. Accordingly, sufficient accuracy may not be ob-
tained by the charge/discharge current at the time of A/D
conversion when the analog signal source of high-impedance is
connected to an analog input pin. In order to obtain the A/D con-
version result stabilized more, please lower the impedance of an
analog signal source, or add the smoothing capacitor to an ana-
log input pin.
Thermistor
Noise
Note : The resistor is used for dividing
N.G.
resistance with a thermistor.
(Note)
O.K.
to 1 k
Microcomputer
resistor to an analog
V
Analog
input pin
SS