Solar Diagrams


12V Solid State Switch Solar Charge Control

This is a Solid State Switch upgrade to the 6A, 12V solar charge regulator. Solid state switching provides longer life, smaller size and higher efficiency than a relay. In addition, the clock frequency may be doubled in order to better track battery load /charging requirements. The parts cost is only slightly higher. One drawback is […]


SCR Based SSS Solar Charge Control

A force-commutated SCR makes a novel Solid State Switch in a solar charge regulator control. Prior art includes relay and transistor switches, but an SCR switch in this type of DC application may be new to the world (normally SCRs are applied in line-commutated AC applications). Advantages include robustness and the requirement of only one […]


6A, 12V Relay Solar Charge Control

This 12V solar charge regulator meets most small-scale application requirements. With a current rating of 6A, it can handle up to a 100W solar panel. Its principle of operation is very simple and there is only one adjustment: cut-out voltage. Many inexpensive commercial solar charges available use, I believe, this technique. However, this particular design […]


6V Solar Charge Shunt Regulator

A shunt regulator technique may be effectively employed in regulating the charging voltage of a lead-acid battery. Although it has a practical power limitation (< 20W or so), it has the notable advantage of being an LDO (low dropout) regulator (zero voltage dropout in this case) - this is in contrast with the typical series […]


3A 6V/12V Solar Charge Control Circuit

This solar charge control combines multiple features into a single design: 3A current rating, low dropout voltage (LDO), range of voltage adjustment (accommodates 6 & 12V lead-acid batteries), reverse polarity protection, low parts cost ($5.90) and low parts count (14 components). High performance is attributed to the application of the common LM358 op amp and […]


Solar Flasher

Notes This circuit is a single transistor flyback (Joule Thief) circuit that features a third coil. With it, flash duration and brightness is much enhanced, without resorting to large value capacitors. The performance can be seen in the following Videos (on Youtube): http://www.youtube.com/watch?v=tgcYcPDbwNo http://www.youtube.com/watch?v=wcHaE4rv64M http://www.youtube.com/watch?v=2HLDPaO9oDM The last is meant to upgrade a Solar Garden Light […]


Solar-cell NiCad Charger, with the MAX639 from Maxim

Parts List: R1 = 820K, 1%R2,R3 = 75K, 1% R4 = 1M, 5%D1,D2 = 1N5817, Schottky diode, or NTE585 L1 = 100uH, coil U1 = MAX639, integrated circuit C1 = 100uF/40V, Electrolytic capacitor C2 = 47uF/40V, Electrolytic capacitor Additional Notes:The MAX639 has its own current limiter build in, set for 200mA.Plenty!Make sure that the charging […]


Solar Panel Tracker

Parts List: All resistors are 1/4 watt, 5%, unless otherwise posted.R1 = 75 OhmR2 = 10K trimmer pot R3,R5 = 33 Ohm R4 = 20K trimmer potR6 = 40 ohm, 1 wattR7,R8,R9 = Photo resistors (LDR)C1 = 0.02uF, polyester (or equivalent)C2 = 0.1uF, ceramicD1 = 1N4004, general purpose silicon diodeQ1 = 2N4401, NPN, general purpose […]


Solar Mailbox project

    Final external Realization  The purpose of this project is to develop a self sufficient Mailbox (real one) that will be powered only by the sun and that will display the number of the house, but only in accordance with the battery level. The system must work autonomously when there is or not enough […]


Voltage regulator for solar panel

This voltage regulator for devices that use solar cells is very simple, require few electronic components. If using a rechargeable energy storage device as a voltage regulator circuit provides charging when the output voltage of the cell is high, and is a minimal charge when the battery output voltage of the cell is low. Since […]