M37516F8HP Renesas Electronics America, M37516F8HP Datasheet - Page 48

• Manufacturer Part Number: M37516F8HP
• Description: IC 740 MCU FLASH 32K 48QFP
• Manufacturer: Renesas Electronics America
• Series: 740/38000r

Specifications of M37516F8HP

• Core Processor: 740
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: I²C, SIO, UART/USART
• Peripherals: PWM, WDT
• Number Of I /o: 38
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 48-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

7516 Group
CLOCK GENERATING CIRCUIT
The 7516 group has two built-in oscillation circuits: main clock X
X
circuit. An oscillation circuit can be formed by connecting a reso-
nator between X
constants in accordance with the resonator manufacturer’s recom-
mended values. No external resistor is needed between X
X
nal feed-back resistor is needed between X
Immediately after power on, only the X
oscillating, and X
Frequency Control
(1) Middle-speed mode
The internal clock
set is released, this mode is selected.
(2) High-speed mode
The internal clock
(3) Low-speed mode
The internal clock
If you switch the mode between middle/high-speed and low-
speed, stabilize both X
is required for the sub-clock to stabilize, especially immediately af-
ter power on and at returning from the stop mode. When switching
the mode between middle/high-speed and low-speed, set the fre-
quency on condition that f(X
(4) Low power dissipation mode
The low power consumption operation can be realized by stopping
the main clock X
bit 5 of the CPU mode register to “1.” When the main clock X
restarted (by setting the main clock stop bit to “0”), set sufficient
time for oscillation to stabilize.
The sub-clock X
clocks that are generated externally. Accordingly, make sure to
cause an external resonator to oscillate.
Oscillation Control
(1) Stop mode
If the STP instruction is executed, the internal clock
“H” level, and X
stabilizing time set after STP instruction released bit is “0,” the
prescaler 12 is set to “FF
oscillation stabilizing time set after STP instruction released bit is
“1,” set the sufficient time for oscillation of used oscillator to stabi-
lize since nothing is set to the prescaler 12 and timer 1.
Either X
count source. Oscillator restarts when an external interrupt is re-
ceived, but the internal clock
at “H”) until timer 1 underflows. The internal clock
the first time, when timer 1 underflows. This ensures time for the
clock oscillation using the ceramic resonators to be stabilized.
When the oscillator is restarted by reset, apply “L” level to the
Rev.1.01
OUT
OUT
Note
since a feed-back resistor exists on-chip. However, an exter-
oscillation circuit and sub clock X
IN
or X
Jul 01, 2003
CIN
IN
CIN
IN
CIN
IN
and X
in low-speed mode. To stop the main clock, set
-X
divided by 16 is input to the prescaler 12 as
and X
is half the frequency of X
is half the frequency of X
is the frequency of X
and X
COUT
IN
CIN
16
and X
OUT
COUT
” and timer 1 is set to “01
oscillation circuit can not directly input
oscillation stops. When the oscillation
IN
page 46 of 89
) > 3•f(X
is not supplied to the CPU (remains
(X
CIN
pins function as I/O ports.
CIN
oscillations. The sufficient time
and X
CIN
IN
).
IN
oscillation circuit starts
CIN
CIN
COUT
divided by 8. After re-
IN
CIN
-X
and X
.
.
). Use the circuit
COUT
is supplied for
16
COUT
.” When the
stops at an
oscillation
.
IN
IN
and
IN
is
-
RESET pin until the oscillation is stable since a wait time will not
be generated.
(2) Wait mode
If the WIT instruction is executed, the internal clock
“H” level, but the oscillator does not stop. The internal clock
starts at reset or when an interrupt is received. Since the oscillator
does not stop, normal operation can be started immediately after
the clock is restarted.
To ensure that the interrupts will be received to release the STP or
WIT state, their interrupt enable bits must be set to “1” before ex-
ecuting of the STP or WIT instruction.
When releasing the STP state, the prescaler 12 and timer 1 will
start counting the clock X
timer 1 interrupt enable bit to “0” before executing the STP instruc-
tion.
When using the oscillation stabilizing time set after STP instruction
released bit set to “1”, evaluate time to stabilize oscillation of the
used oscillator and set the value to the timer 1 and prescaler 12.
Fig. 52 Ceramic resonator circuit
Fig. 53 External clock input circuit
Note
X
C I N
C
R f
C I N
X
C O U T
X
R d
C
C I N
C O U T
C
R f
C I N
X
E x t e r n a l o s c i l l a t i o n
c i r c u i t
X
Vcc
V s s
C O U T
I N
R d
C
IN
C O U T
divided by 16. Accordingly, set the
X
O p e n
O U T
X
I N
C
I N
X
O U T
C
O U T
stops at an
re-