RX110_16 Datasheet, PDF (95/108 Pages) Renesas Technology Corp – 32 MHz 32-bit RX MCUs, 50 DMIPS

RX110 Group
5. Electrical Characteristics
5.9 Usage Notes
5.9.1
Connecting VCL Capacitor and Bypass Capacitors
This MCU integrates an internal voltage-down circuit, which is used for lowering the power supply voltage in the
internal MCU to adjust automatically to the optimum level. A 4.7-μF capacitor needs to be connected between this
internal voltage-down power supply (VCL pin) and VSS pin. Figure 5.54 to Figure 5.55 shows how to connect
external capacitors. Place an external capacitor close to the pins. Do not apply the power supply voltage to the VCL pin.
Insert a multilayer ceramic capacitor as a bypass capacitor between each pair of the power supply pins. Implement a
bypass capacitor to the MCU power supply pins as close as possible. Use a recommended value of 0.1 μF as the
capacitance of the capacitors. For the capacitors related to crystal oscillation, see section 9, Clock Generation Circuit
in the User’s Manual: Hardware. For the capacitors related to analog modules, also see section 27, 12-Bit A/D
Converter (S12ADb) in the User’s Manual: Hardware.
For notes on designing the printed circuit board, see the descriptions of the application note "Hardware Design Guide"
(R01AN1411EJ). The latest version can be downloaded from Renesas Electronics Website.
Bypass
capacitor
0.1 µF
Bypass
capacitor
0.1 µF
49
32
50
31
51
30
52
29
53
28
54
RX110 Group
27
55
PLQP0064KB-A
26
56
25
PLQP0064GA-A
57
24
58
(64-pin LFQFP/LQFP)
23
59
(Top view)
22
60
21
61
20
62 AVSS0
19
63 AVCC0
18
64
17
Bypass Bypass
capacitor capacitor
4.7 µF 0.1 µF
Note. Do not apply the power supply voltage to the VCL pin.
Use a 4.7-µF multilayer ceramic for the VCL pin and place it close to the pin.
A recommended value is shown for the capacitance of the bypass capacitors.
Figure 5.54 Connecting Capacitors (64 Pins)
R01DS0202EJ0120 Rev.1.20
Jul 29, 2016
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