!Operation:!1. Connect an external power source to J1 (+ and - IN terminals). The

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Aubrey Weaver
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1 The CB500 Electronic Circuit Breaker is an resettable circuit breaker (fuse) that disconnects power when the trip setting is exceeded. There are 4 trip settings that can easily be changed and set during operation. When an overload is detected, power is disconnected within 6 milliseconds protecting the power source and powered circuits from damage. Once the overload condition is corrected, the user manually resets the CB500 to restore power. Operation: 1. Connect an external power source to J1 (+ and - IN terminals). The CB500 Electronic Circuit Breaker Kit Rev A resettable electronic fuse that disconnects dc power to protect power sources and breadboarded components. Replaces single use fuses. Plugs into power rails of standard prototyping breadboards. Operates with power sources between volts dc. 4 current trip settings: 50, 100, 250 and 500 ma dc. Trip response: < 6 milliseconds. Low voltage burden: 250 mv at 500 ma setting. Power requirements: vdc, 20 ma. 7. power source can be any dc power source with an output of 3.5 volts minimum and 16.0 volts maximum. Connect the load to J2 (+ and - OUT terminals). Or insert the CD500 PCB between the power buses on your prototyping breadboard. Turn the power source on. The current trip setting is displayed by the lit LED. If the CB500 trips, temporarily remove the load and press the Set/Rst button. Then select a higher trip point using the increase ( >) button and press Set/Rst. Then reconnect the load. Change the trip setting with the decrease(< ) and increase ( >) buttons. Press Set/Rst to save the trip setting. If the load current exceeds the trip setting, the CB500 will trip, disconnect power to the load, and flash the trip point LED. Correct the problem and press Set/Rst to restore power. The CB500 utilizes a.500 ohm sense resistor to determine the current flowing to the load. This current causes a voltage drop across the sense resistor that subtracts from the voltage of the power source. The voltage delivered to the load is thus the power source voltage less the voltage drop across the sense resistor. In general, for every milliamp of load current, there is a.5 millivolt drop across the sense resistor. The table on page 2 shows the maximum voltage drop for each of the trip settings. NOTE: Since the CB500 senses the current in the ground lead, the ground or minus leads of the power source and the load must be kept separate. Connecting the minus lead of the power source directly to the minus lead for the load will bypass the circuit breaking function of the CB500. 1

2 Trip Point Setting CB500 Voltage Drop Maximum 50 ma 25 mv 100 ma 50 mv 250 ma 125 mv 500 ma 250 mv We suggest assembling the kit in the following sequence: Assembly: All components are inserted from the component side (side with the white lettering) of the circuit board. The circuit board is labeled with the outlines and IDs of all components. Certain parts are polarity sensitive and must be installed correctly. Solder all parts and trim off the excess lead lengths before moving to the next step Install R1. This is the sense resistor and is surface mounted on the top side of the PCB. Place the resistor between the pads and hold it down using the point of a set of tweezers or a small screw driver. Reheat and reflow the solder on one pad and then the other. Once R1 is secure, go back and add additional solder if necessary to each pad. Install voltage regulator U1. Use the same technique as in step 1. Install LED1, LED2, LED3 and LED4. They are polarity sensitive and must be inserted with the cathode (short) lead into the square pad. Insert all 4 LEDs, flip the PCB over and solder only one of the pads on each LED. Check that all LEDs are mounted straight and against the top of the PCB. Reheat the soldered joints if necessary to adjust. When done, solder the remaining pad on each LED. Install 3 ea 22k ohm (red-red-orn-gold) resistors at locations R2, R3 and R4. Install 4 ea 1.0k ohm (brn-blk-red-gold) resistors at locations R6, R7, R8 and R9. Install 1 ea 4.7k ohm (yel-vio-red-gold) resistor at location R5. Install diodes D1 (large body) and D2 (small body). They are polarity sensitive and must be installed with the banded end in the proper direction shown on the PCB. Install terminal blocks J1 and J2. Insert the blocks with the wire entry holes facing the edge of the PCB. Turn the PCB over and solder one terminal on each block. Check alignment and reheat solder joint if necessary. Then solder the remaining pad. 2

3 Insert the long side of the 2-pin headers into your prototyping board as shown. Install capacitor C1. This capacitor is polarity sensitive. Look at the part supplied with the kit. Either the + terminal or the - terminal will be clearly marked. Insert the capacitor so that the + terminal is in the pad with the adjacent + sign. Solder in place. 10. Install capacitors C2 and C3. Solder in place. 11. Install U2. Insert U2 with the notch on the chip aligned with the notch on the PCB. Solder all pins. 12. shown Install relay K1. Insert from the top side of the PCB and turn over. 18. Place the assembled PCB over the headers so that they align with the 4 sets of pads in the PCB. Carefully and quickly solder the pins to the pads from the top side of the PCB. Solder one pin and then check to make sure relay is flat against the PCB. Reheat soldered joint if necessary. Solder remaining pins. 13. Install MOSFET Q1. Insert Q1 with the metal side closer to the heavier outline on the PCB. Solder all pins. Note: If the pads do not line up correctly, your breadboard may not have the right spacing to mount the CB500 across the power busses. You can still use the CB500 by installing the output pins only and supplying power through terminal block J1 (IN). 19. Check all solder joints and retouch if necessary. Wash PCB with alcohol to remove all flux residue. Dry before testing. Testing: 1. Connect your power source to J1 (IN) or to the upper power bus of your 2. breadboard. Turn on power. CB500 will power up and after a short delay, supply to the output terminals. 3. power on LED shows the previously saved trip point. 4. The the arrow buttons to change the trip point. 5. Press Press the Set/Rst button to save the setting. The LED will blink once. 14. Install switches SW1, SW2, and SW3. Insert the switches from the top side of the PCB and press firmly to seat them in place. Solder all pins. 15. If you want to use your new CB500 with standard prototyping breadboards, do the next steps to solder in header pins. These header pins will stick out the back side of the PCB and plug into the power busses of the breadboard. Otherwise you can use the CB500 as is by making connections using terminal blocks J1 (IN) and J2 (OUT). 16. Carefully separate the breakable header strip into 4 2-pin headers. 3

4 6. Place a load across the output terminal J2 (OUT) that exceeds the trip point setting. The CB500 will trip and disconnect power to the load. The trip point LED flashes to indicate the tripped condition. 7. Press Set/Rst to restore power to the load. Verify the trip point setting is the previously saved selection. 8. Momentarily short the output terminal J2 (OUT), CB500 will trip and automatically reset. For assistance, please contact us at support@powerswitchtail.com. Soft copy of this and related documents can be found at Parts List: C1 ID Description Capacitor, Electrolytic, 47mf, 16v C2, C3 Capacitor,.1mf, 50v, mono ceramic D1 D2 Diode, IN4401, 100 PIV, 1amp Diode, 1N4148 J1, J2 Terminal block, 2 contact, 3.5mm K1 LED1, LED2, LED3, LED4 Q1 R1 Relay, NA5W-K, 5vdc coil, 2 amp contacts LED, 3mm, Red MOSFET, RFD ohm, 1%, thick film, SMD R2, R3, R4 22k ohm, 5%, 1/4w, carbon film R5 4.7k ohm, 5%, 1/4w, carbon film R6, R7, R8, R9 1.0k ohm, 5%, 1/4w, carbon film SW1, SW2, SW3 U1 U2 PCB Header strip Switch, momentary, pushbutton, 5mm tactile MIC2920A. 3.3v LDO Regulator, SMD PIC16F1823, custom programed PowerSwitchTail, CB500, Ver 1.2 Circuit Board Our liability is limited to the purchase price of this product only. By using this product you agree that PowerSwitchTail.com, LLC cannot be held liable for any damages or injuries resulting from use or repairs. 4

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Joule Thief 3.0 Kit. June 2012, Rev 1 1 http://www.easternvoltageresearch.com Joule Thief 3.0

Joule Thief 3.0 Kit. June 2012, Rev 1 1 http://www.easternvoltageresearch.com Joule Thief 3.0 Kit Instruction Manual Eastern Voltage Research, LLC June 2012, Rev 1 1 http://www.easternvoltageresearch.com HIGH BRIGHTNESS LED THIS KIT USES A 1W CREE, HIGH BRIGHTNESS LED. DO NOT STARE AT THIS (OR