R5F21191SP#U0 Renesas Electronics America, R5F21191SP#U0 Datasheet - Page 43

• Manufacturer Part Number: R5F21191SP#U0
• Description: IC R8C MCU FLASH 8K 20SSOP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M16C/R8C/Tiny/19r

Specifications of R5F21191SP#U0

• Core Processor: R8C
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: SIO, UART/USART
• Peripherals: LED, POR, Voltage Detect, WDT
• Number Of I /o: 13
• Program Memory Size: 4KB (4K x 8)
• Program Memory Type: FLASH
• Ram Size: 384 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 4x1b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 20-SSOP
• For Use With: R0K521134S000BE - KIT EVAL STARTER FOR R8C/13R0E521174CPE10 - EMULATOR COMPACT R8C/18/19/1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

R8C/18 Group, R8C/19 Group
Rev.1.30
REJ09B0222-0130
5.2
Figure 5.6
NOTES:
When the RESET pin is connected to the VCC pin via a pull-up resistor of about 5 kΩ, and the VCC pin
voltage level rises, the power-on reset function is enabled and the MCU resets its pins, CPU, and SFR.
When a capacitor is connected to the RESET pin, always keep the voltage to the RESET pin 0.8VCC or
more.
When the input voltage to the VCC pin reaches the Vdet1 level or above, the low-speed on-chip
oscillator clock starts counting. When the low-speed on-chip oscillator clock count reaches 32, the
internal reset signal is held “H” and the MCU enters the reset sequence (refer to Figure 5.3). The low-
speed on-chip oscillator clock divided by 8 is automatically selected as the CPU after reset.
Refer to 4. Special Function Registers (SFRs) for the status of the SFR after power-on reset.
The voltage monitor 1 reset is enabled after power-on reset.
Figure 5.6 shows an Example of Power-On Reset Circuit and Operation.
1. The supply voltage must be held within the MCU’s operating voltage range (Vccmin or above) over the sampling time.
2. A sampling clock can be selected. Refer to 7. Voltage Detection Circuit for details.
3. Vdet1 indicates voltage detection level for the voltage detection 1 circuit. Refer to 7. Voltage Detection Circuit for details.
4. Refer to 18. Electrical Characteristics.
Internal reset signal
Power-On Reset Function
Apr 14, 2006
(active “L”)
About
5 kΩ
Example of Power-On Reset Circuit and Operation
V
V
det1
por1
(3)
VCC
RESET
Page 26 of 233
t
w(por1)
t
w(Vpor1–Vdet1)
f
RING-S
1
× 32
Sampling time
RESET
VCC
0 V
0 V
(1, 2)
0.1 V to 2.7 V
t
w(por2)
within td(P-R)
t
w(Vpor2–Vdet1)
V
Vccmin
por2
0.8 VCC or above
f
RING-S
1
× 32
V
det1
5. Resets
(3)