AT89C5131A-M Atmel Corporation, AT89C5131A-M Datasheet - Page 151

no-image

AT89C5131A-M

Manufacturer Part Number
AT89C5131A-M
Description
Manufacturer
Atmel Corporation
Datasheets

Specifications of AT89C5131A-M

Flash (kbytes)
32 Kbytes
Max. Operating Frequency
48 MHz
Cpu
8051-12C
Max I/o Pins
34
Usb Transceiver
1
Usb Speed
Full Speed
Usb Interface
Device
Spi
1
Twi (i2c)
1
Uart
1
Sram (kbytes)
1.25
Eeprom (bytes)
1024
Self Program Memory
API
Operating Voltage (vcc)
2.7 to 5.5
Timers
4
Isp
UART/USB
Watchdog
Yes
22. Reset
22.1
22.2
22.3
4337K–USB–04/08
Introduction
Reset Input
Reset Output
The reset sources are: Power Management, Hardware Watchdog, PCA Watchdog and Reset
input.
Figure 22-1. Reset schematic
The Reset input can be used to force a reset pulse longer than the internal reset controlled by
the Power Monitor. RST input has a pull-up resistor allowing power-on reset by simply connect-
ing an external capacitor to V
characteristics are discussed in the Section “DC Characteristics” of the AT89C5130A/31A-M
datasheet.
Figure 22-2. Reset Circuitry and Power-On Reset
As detailed in Section “Hardware Watchdog Timer”, page 158, the WDT generates a 96-clock
period pulse on the RST pin. In order to properly propagate this pulse to the rest of the applica-
tion in case of external capacitor or power-supply supervisor circuit, a 1 kΩ resistor must be
added as shown Figure 22-3.
RST
RST
Watchdog
Watchdog
Hardware
Monitor
Power
PCA
a. RST input circuitry
VCC
S S
as shown in Figure 22-2. Resistor value and input
To internal reset
AT89C5130A/31A-M
b. Power-on Reset
Internal Reset
VSS
+
RST
151

Related parts for AT89C5131A-M