18
18-2
Ver.0.10
OSCILLATION CIRCUIT
18.1 Oscillator Circuit
Figure 18.1.1 Example of a System Clock Generating Circuit
18.1 Oscillator Circuit
The M32R/E contains an oscillator circuit that supplies operating clocks for the CPU core, internal
peripheral I/O, and internal memory. The frequency fed to the clock input pin (XIN) is multiplied by
4 by the internal PLL circuit to produce the CPU clock, which is the operating clock for the CPU core
and internal memory. The frequency of this clock is divided by 2 in the subsequent circuit to
produce the internal peripheral clock, which is the operating clock for the internal peripheral I/O.
18.1.1 Example of an Oscillator Circuit
A clock generating circuit can be configured by connecting a ceramic (or crystal) resonator between
the XIN and XOUT pins external to the chip. Figure 18.1.1 below shows an example of a system
clock generating circuit using a resonator connected external to the chip and an RC network
connected to the PLL circuit control pin (VCNT). For constants Rf, CIN, COUT, and Rd, consult
your resonator manufacturer to determine the appropriate values.
When you use an externally sourced clock signal without using the internal oscillator circuit,
connect the external clock signal to the XIN pin and leave the XOUT pin open.
M32R/E
OSCVCC
XIN
XOUT
OSCVSS
Rf
Rd
C
IN
C
OUT
VCNT
BCLK / P70
C
Oscillator
circuit
To internal
peripheral
clock
PLL circuit
220pF
0.1µF
1K
Ω
Oscillator module
OSCVCC : 3.3 V power supply
To CPU clock
1/2
Summary of Contents for M32170F3VFP
Page 42: ...1 1 24 Ver 0 10 OVERVIEW 1 4 Pin Layout This is a blank page ...
Page 56: ...2 2 14 Ver 0 10 This is a blank page ...
Page 88: ...3 3 32 Ver 0 10 ADDRESS SPACE 3 7 Notes on Address Space This is a blank page ...
Page 270: ...9 9 40 Ver 0 10 DMAC 9 4 Precautions about the DMAC This is a blank page ...
Page 614: ...12 12 64 Ver 0 10 This is a blank page SERIAL I O 12 9 Precautions on Using UART Mode ...
Page 756: ...17 17 10 Ver 0 10 RAM BACKUP MODE 17 4 Exiting RAM Backup Mode Wakeup This is a blank page ...
Page 762: ...18 18 6 Ver 0 10 OSCILLATION CIRCUIT 18 2 Clock Generator Circuit This is a blank page ...
Page 831: ...CHAPTER 22 CHAPTER 22 TYPICAL CHARACTERISTICS 22 1 A D Conversion Characteristics ...
Page 833: ...Appendix 1 1 Dimensional Outline Drawing APPENDIX 1 APPENDIX 1 MECHANICAL SPECIFICATIONS ...
Page 841: ...Appendix 3 1 Precautions about Noise APPENDIX 3 APPENDIX 3 PRECAUTIONS ABOUT NOISE ...