SH7055S Datasheet, PDF (945/1002 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7000 Series

26.6 Usage Note
26.6.1 Notes on Connecting External Capacitor for Current Stabilization
The SH7055SF includes an internal step-down curcuit to automatically reduce the
microporocessor power supply voltage to an appropriate level. Between this internal stepped-
down power supply (V_CL pin) and the V_SS pin, an capacitor (0.33 to 0.47 µF) for stabilizing the
internal voltage. Connection of the external capacitor is shown in figure 26.29. The external
capacitor should be located near the pin. Do not apply any power supply voltage to the V_CL pin.
External power-supply
stabilizing capacitor
One 0.33 to 0.47 µF capacitor
One 0.33 to 0.47 µF
capacitor
VCL ^VCL
VSS
VSS _VCL
VSS
One 0.33 to 0.47 µF
capacitor
Do not apply any power supply voltage to the VCL pin.
Use multilayer ceramics capacitors (one 0.33 to 0.47 µF
capacitor for each VCL pin), which should be located
near the pin.
Figure 26.29 Connection of V_CL Capacitor
26.6.2 Notes on Mode Pin Input
When power is supplied and in hardware standby mode, mode setup time is determined by
tMDS1. When power-on reset is performed only by the RES pin, mode setup time is differs
according to the combination of input to the FWE and MD2 to MD0. When low is input to the
RES pin with the pins FWE and MD2 to MD0 operated in mode specified in table 26.3, the mode
setup time is determined by tMDS2. When combination which is not specified in table 26.3 is
input, the mode setup time is determined by tMDS1.
Rev.2.0, 07/03, page 907 of 960