AT89C5131A-PUTIM Atmel, AT89C5131A-PUTIM Datasheet - Page 151

• Manufacturer Part Number: AT89C5131A-PUTIM
• Description: IC 8051 MCU FLASH 32K USB 32QFN
• Manufacturer: Atmel
• Series: AT89C513xr

Specifications of AT89C5131A-PUTIM

• Core Processor: C52X2
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: LED, POR, PWM, WDT
• Number Of I /o: 18
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-VQFN Exposed Pad, 32-HVQFN, 32-SQFN, 32-DHVQFN
• For Use With: AT89STK-10 - KIT EVAL APPL MASS STORAGEAT89STK-05 - KIT STARTER FOR AT89C5131
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Data Converters: -

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
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