AT89C51RC2 Atmel Corporation, AT89C51RC2 Datasheet - Page 81
AT89C51RC2
Manufacturer Part Number
AT89C51RC2
Description
Manufacturer
Atmel Corporation
Specifications of AT89C51RC2
Flash (kbytes)
32 Kbytes
Max. Operating Frequency
60 MHz
Cpu
8051-12C
Max I/o Pins
32
Spi
1
Uart
1
Sram (kbytes)
1.25
Self Program Memory
API
Operating Voltage (vcc)
2.7 to 5.5
Timers
4
Isp
UART
Watchdog
Yes
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
AT89C51RC2-3CSUM
Manufacturer:
ATMEL
Quantity:
15 569
Company:
Part Number:
AT89C51RC2-CM
Manufacturer:
ATMEL
Quantity:
8 831
Part Number:
AT89C51RC2-CM
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Company:
Part Number:
AT89C51RC2-IM
Manufacturer:
ATMEL
Quantity:
719
Part Number:
AT89C51RC2-IM
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Company:
Part Number:
AT89C51RC2-RLRIL
Manufacturer:
Atmel
Quantity:
1 495
Company:
Part Number:
AT89C51RC2-RLTIL
Manufacturer:
ATMEL
Quantity:
5 000
Part Number:
AT89C51RC2-RLTUM
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Warm Reset
Watchdog Reset
4180E–8051–10/06
Table 1. Minimum Reset Capacitor Value for a 50 kΩ Pull-down Resistor
Note:
To achieve a valid reset, the reset signal must be maintained for at least 2 machine
cycles (24 oscillator clock periods) while the oscillator is running. The number of clock
periods is mode independent (X2 or X1).
As detailed in Section “Hardware Watchdog Timer”, page 77, the WDT generates a 96-
clock period pulse on the RST pin. In order to properly propagate this pulse to the rest of
the application in case of external capacitor or power-supply supervisor circuit, a 1 kΩ
resistor must be added as shown Figure 33.
Figure 33. Reset Circuitry for WDT Reset-out Usage
Start-Up Time
Oscillator
20 ms
These values assume V
on/off sequences is too fast, the power-supply de-coupling capacitors may not be fully
discharged, leading to a bad reset sequence.
5 ms
VDD
VDD
VSS
+
RST
1K
820 nF
2.7 µF
1 ms
DD
RST
starts from 0V to the nominal value. If the time between 2
VDD
VSS
P
VDD Rise Time
10 ms
1.2 µF
3.9 µF
AT89C51RB2/RC2
From WDT
Reset Source
To CPU Core
and Peripherals
To Other
On-board
Circuitry
100 ms
(1)
12 µF
12 µF
81