Книга: Advanced PIC Microcontroller Projects in C
2.1.4 The Power Supply
2.1.4 The Power Supply
The power supply requirements of the PIC18F452 microcontroller are shown in Figure 2.9. As shown in Figure 2.10, PIC18F452 can operate with a supply voltage of 4.2V to 5.5V at the full speed of 40MHz. The lower power version, PIC18LF452, can operate from 2.0 to 5.5 volts. At lower voltages the maximum clock frequency is 4MHz, which rises to 40MHz at 4.2V. The RAM data retention voltage is specified as 1.5V and will be lost if the power supply voltage is lowered below this value. In practice, most microcontroller-based systems are operated with a single +5V supply derived from a suitable voltage regulator.
Figure 2.9: The PIC8F452 power supply parameters
Figure 2.10: Operation of PIC18LF452 at different voltages
Оглавление книги
- 2.1.1 Program Memory Organization
- 2.1.2 Data Memory Organization
- 2.1.3 The Configuration Registers
- 2.1.4 The Power Supply
- 2.1.5 The Reset
- 2.1.6 The Clock Sources
- 2.1.7 Watchdog Timer
- 2.1.8 Parallel I/O Ports
- 2.1.9 Timers
- 2.1.10 Capture/Compare/PWM Modules (CCP)
- 2.1.11 Analog-to-Digital Converter (A/D) Module
- 2.1.12 Interrupts
- 1.3.1 Supply Voltage
- 1.3.15 Power-on Reset
- 1.3.16 Low-Power Operation
- 1.3.21 Ethernet Interface
- 4.4.4 The Dispatcher
- About the author
- Chapter 7. The state machine
- Appendix E. Other resources and links
- Example NAT machine in theory
- The final stage of our NAT machine
- Compiling the user-land applications
- The conntrack entries