PIC16F1782 has got built in almost all components needed to build a switching regulator. I've already tested a possibility of building step down regulator utilizing a microcontroller with "advanced analog peripherals". This time I would like to build a true maximum power point tracking converter for a solar panel.
My monocrystalline test solar panel is rated with:
Peak Power (Pm) 10W
Open Circuit Voltage (Voc) 21.67V
Short Circuit Current (Isc) 0.61A
Maximum Power Voltage (Vmp) 17.49V
Maximum Power Current (Imp) 0.57A
Maximum power voltage is lower than voltage needed to charge a 12V lead battery so I need a step-down converter:
I found it difficult to arrange which pins should be connected to which signals. There are some alternatives on which pins periferals are connected and it is rather difficult to notice the best arrangement looking only at schematic. It is much easier to notice every possibilities and clashes on a spreadshit like this:
| pin | 1st | 2nd | ||||||||
| RA0 | 2 | AN0 | CxIN0- | COMP_I | ||||||
| RA1 | 3 | AN1 | CxIN1- | OPA1OUT | PV_I_SHUNT | |||||
| RA2 | 4 | AN2 | CxIN0+ | COMP_I | ||||||
| RA3 | 5 | AN3 | C1IN+ | PV_I_FBK | ||||||
| RA4 | 6 | C1OUT | OPA1IN+ | PV_I_SHUNT | ||||||
| RA5 | 7 | AN4 | C2OUT | OPA1IN- | PV_I_SHUNT | |||||
| RA6 | 10 | C2OUT | COMP_I | |||||||
| RA7 | 9 | PSMCxCLK | ||||||||
| RB0 | 21 | AN12 | C2IN1+ | PSMCxIN | CCP1(2) | STOP_SWITCHING | ||||
| RB1 | 22 | AN10 | CxIN3- | OPA2OUT | COMP_V | |||||
| RB2 | 23 | AN8 | OPA2IN- | PV_U_FBK | ||||||
| RB3 | 24 | AN9 | CxIN2- | OPA2IN+ | CCP2(2) | OUT_V_FBK | ||||
| RB4 | 25 | AN11 | C3IN+ | COMP_V | ||||||
| RB5 | 26 | AN13 | C3OUT | COMP_V | ||||||
| RB6 | 27 | TX(2) | ICSPCLK | PROG | TX | |||||
| RB7 | 28 | RX(2) | ICSPDAT | PROG | RX | |||||
| RC0 | 11 | PSMC1A | ||||||||
| RC1 | 12 | PSMC1B | CCP2(1) | PV_I_SET_PWM | ||||||
| RC2 | 13 | PSMC1C | CCP1(1) | PV_V_SET_PWM | ||||||
| RC3 | 14 | PSMC1D | ||||||||
| RC4 | 15 | PSMC1E | LED2 | |||||||
| RC5 | 16 | PSMC1F | LED1 | |||||||
| RC6 | 17 | PSMC2A | TX(1) | DRIVE_HS | ||||||
| RC7 | 18 | PSMC2B | RX(1) | DRIVE_LS | ||||||
| RE3 | 1 | PROG | ||||||||
| VDD | 20 | |||||||||
| VSS | 8 | |||||||||
| VSS | 19 |
