SH7710 Datasheet, PDF (371/996 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 11 On-Chip Oscillation Circuits
11.9 Notes on Board Design
When Using an External Crystal Resonator: Place the crystal resonator, capacitors CL1 and
CL2, and damping resistor R close to the EXTAL and XTAL pins. To prevent induction from
interfering with correct oscillation, use a common grounding point for the capacitors connected to
the resonator, and do not locate a wiring pattern near these components.
Avoid crossing
signal lines
CL1
CL2
EXTAL
R
XTAL
This LSI
Note: The values for CL1, CL2, and the damping resistance should be determined after
consultation with the crystal manufacturer.
Figure 11.4 Points for Attention when Using Crystal Resonator
Bypass Capacitors: Insert a laminated ceramic capacitor as a bypass capacitor for each Vss/VssQ
and Vcc/VccQ pair. Mount the bypass capacitors to the power supply pins, and use components
with a frequency characteristic suitable for the operating frequency of the LSI, as well as a suitable
capacitance value.
Pin assignments of HQFP2828-256 (FP-256G/GV)
Vss/VssQ and Vcc/VccQ pair of digital circuitry
3 and 4, 13 and 14, 15 and 16, 25 and 26, 35 and 36, 43 and 44, 49 and 50, 57 and 58, 72 and
73, 81 and 82, 83 and 84, 92 and 93, 99 and 100, 107 and 108, 113 and 114, 121 and 122, 136
and 137, 146 and 147, 148 and 149, 158 and 159, 167 and 168, 176 and 177, 185 and 186, 191
and 192, 206 and 207, 208 and 209, 221 and 222, 227 and 228, 235 and 236, 241 and 242
Vss/VssQ and Vcc/VccQ pair of the on-chip oscillator
193 and 196, 251 and 252, 253 and 254
Rev. 2.00 Dec. 07, 2005 Page 329 of 950
REJ09B0079-0200