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Hi...
I am using PIC18F452 and I have connected (MCP130"Microcontroller supervisory circuit") in the MCLR pin No.1 of microcontroller.
When Vdd 5V is given to the controller ,it takes 270 ms to turn ON the microcontroller.
How to minimize the delay and quickly turn ON (less than 50 ms) the controller after Vdd=5V is given.
Please suggest some tips, related documents.
I suggest reading the datasheet for the chip you are using.Quote:
How to minimize the delay and quickly turn ON (less than 50 ms) the controller after Vdd=5V is given.
If you are getting the PIC running in 270mS you are doing well. 50mS will not be acheivable using that chip.
From the first page of the datasheet.....
2001 Microchip Technology Inc. DS11184D-page 1
MCP120/130
FEATURES
• Holds microcontroller in reset until supply voltage reaches stable operating level
• Resets microcontroller during power loss
• Precision monitoring of 3V, 3.3V and 5V systems
• 7 voltage trip points available
• Active low RESET pin
• Open drain output
• Internal pull-up resistor (5 kΩ) for MCP130
• Holds RESET for 350 ms (typical)
• RESET to VCC = 1.0V
• Accuracy of ±125 mV for 5V systems and ±75 mV for 3V systems over temperature
• 45 μA typical operating current
• Temperature range:- Industrial (I): -40°C to +85°C
DESCRIPTION
The Microchip Technology Inc. MCP120/130 is a voltage supervisory device designed to keep a microcontroller in reset until the system voltage has reached the proper level and stabilized. It also operates as protection from brown-out conditions when the supply voltage drops below a safe operating level. Both devices are available with a choice of seven different trip voltages and both have open drain outputs. The MCP130 has an internal 5 kΩ pullup resistor. Both devices have active low RESET pins. The MCP120/130 will assert the RESET signal whenever the voltage on the VDD pin is below the trip-point voltage.