M306N5FCTFP Renesas Electronics America, M306N5FCTFP Datasheet - Page 75

• Manufacturer Part Number: M306N5FCTFP
• Description: IC M16C MCU FLASH 100QFP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M16C/6Nr

Specifications of M306N5FCTFP

• Core Processor: M16C/60
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: CAN, I²C, IEBus, SIO, UART/USART
• Peripherals: DMA, WDT
• Number Of I /o: 87
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 5K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 26x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

M16C/6N Group (M16C/6N5)
Rev.2.40
REJ09B0011-0240
Figure 8.9 Examples of Main Clock Connection Circuit
The following describes the clocks generated by the clock generation circuit.
8.1.1 Main Clock
The main clock is generated by the main clock oscillation circuit. This clock is used as the clock source for
the CPU and peripheral function clocks. The main clock oscillation circuit is configured by connecting a
resonator between pins XIN and XOUT. The main clock oscillation circuit has an on-chip feedback resistor,
which is disconnected from the oscillation circuit during stop mode in order to reduce the amount of power
consumed in the chip. The main clock oscillation circuit may also be configured by feeding an externally
generated clock to the XIN pin. Figure 8.9 shows an Examples of Main Clock Connection Circuit.
After reset, the main clock divided by 8 is selected for the CPU clock.
The power consumption in the chip can be reduced by setting the CM05 bit in the CM0 register to 1 (main
clock oscillation circuit turned off) after switching the clock source for the CPU clock to a sub clock or on-chip
oscillator clock. In this case, XOUT goes “H”. Furthermore, because an on-chip feedback resistor remains
on, XIN is pulled “H” to XOUT via the feedback resistor. Note, that if an externally generated clock is fed
into the XIN pin, the main clock cannot be turned off by setting the CM05 bit to 1, unless the sub clock is
selected as a CPU clock. If necessary, use an external circuit to turn off the clock.
During stop mode, all clocks including the main clock are turned off. Refer to 8.4 Power Control.
(On-chip feedback resistor)
Apr 14, 2006
NOTE:
1.Place a damping resistor if required. The resistance will vary depending on the oscillator
and the oscillation drive capacity setting. Use the value recommended by each oscillator
the oscillator manufacturer.
When the oscillation drive capacity is set to low, check that oscillation is stable.
Also, place a feedback resistor between XIN and XOUT if the oscillator manufacturer
recommends placing the resistor externally.
MCU
XOUT
page 53 of 372
VSS
XIN
Oscillator
Rd
(1)
COUT
CIN
(On-chip feedback resistor)
MCU
XOUT
XIN
Open
VCC
VSS
External clock
8. Clock Generation Circuit