CirKits.com LVD1-a1 Low Voltage Disconnect Assembly Instructions Instructions Rev: December 27, 2013 Check http://www.cirkits.com/lvd1 for update information. General Hints and Tips: -Parts go on the side of the board with white lettering (silkscreen). -Do not overheat the semiconductors when soldering, especially the LEDs. -Use a clip-on heat sink on semiconductor leads during soldering. -Only use electronic grade 60/40 rosin core solder or equivalent. -Acid core solder destroys electronic parts, don't use it. -A proper solder connection is shiny, smooth, and concave shaped. -Look at the photograph of an assembled DAS1 circuit board on http://www.cirkits.com/das1/ for reference. -When working with long leaded parts, insert the leads into the board holes, bend the leads so that the part fits snugly to the board, solder the leads, then clip off the excess wire. Tools and materials for Construction and Alignment: Electronic grade Soldering Iron 60/40 rosin core solder Needle nose pliers Diagonal wire cutters #1 Phillips head screw driver Fine gauge flat screw driver for circuit adjustment volt meter Rubbing Alcohol and a tooth brush (recommended) 0-20 VDC variable power supply Follow and check all of the [] boxes as you proceed. Solder the resistors to the board. If you are unsure about the resistor color codes, verify the part values with an ohm-meter. [] Solder one 10 ohm (brown black black) resistor at R23. [] Solder two 330 ohm (orange orange brown) resistors at R16,R17. [] Solder one 750 ohm (violet green brown) resistor at R14. [] Solder five 1K (brown black red) resistors at R9,R10,R11,R12,R13. [] Solder one 10K (brown black orange) resistor at R15. [] Solder four 47K (yellow violet orange) resistors at R2,R4,R5,R6. [] Solder one 56K (green blue orange) resistor at R3. [] Solder one 68K (blue gray orange) resistor at R1. [] Solder five 100K (brown black yellow) resistors at R18,R19,R20,R21, R22. [] Solder one 1M (brown black green) resistor at R8. [] Solder one 2M (red black green) resistor at R7. [] Solder the 470uF capacitor to the board at C10. The long lead on the capacitor goes in the hole with the + sign, the white - stripe on the capacitor is closer to the edge of the board. [] Solder one 4.7nF capacitor (marked 472 or 502) at C1. [] Solder two 1uF capacitors (marked 105 or 1.0) at C8,C9. Ignore the polarity marking on the board at C8. [] Solder six 100nF capacitors (marked 104 or 0.1) at C2,C3,C4,C5,C6,C7. The stripe on the diodes should line up with the white line on the white line on the circuit board silkscreen. [] Solder one 1N5818 Schottky diode at D4. [] Solder three 1N4148 diodes at D1,D2,D3. [] Solder the 78L05 5V regulator to the board at VR1. Align the flat side of the regulator with the board marking. [] Solder the 2N3904 transistor to the board at Q1. Align the flat side of the transistor with the board marking. [] Bend the leads of Q2, the IRLZ44N MOSFET, so that the part fits into the board and the mounting hole lines up with the circuit board hole. [] Use the toothpick and apply a thin layer of heat sink grease from the plastic capsule to the back side of Q1. Install Q1 on the board using the 4-40 screw, lock washer, and nut. Bend the Q1 leads over the silvered areas on the bottom of the board, then solder the leads. [] Insert the blue 15A fuse into the two fuse clips and solder the fuse assembly to the board at the location marked F1. The flat side of the clips go toward connector CN1. There are two types of toggle switches, on-off-(on): S2 and on-on: S1. [] Solder the on-off-(on) SPDT switch to the board at S2. [] Solder the on-on SPDT switch to the board at S1. [] Solder the three 20K potentiometers (marked W203) to the board at RV1,RV2,RV3. The adjustment screws should be near the board edge. All of the LEDs have a flat side, this should line up with the board markings. The LEDs can face up or forward, depending on how you plan on mounting the board. [] Solder the red LED to the board at LED1. [] Solder the amber LED to the board at LED4. [] Solder the two green LEDs to the board at LED2,LED3. [] Solder the TLC27L4N quad R2R op-amp to the board at IC1, align the notch on the top of the IC with the notch on the board silkscreen. [] Solder the CD4013 dual CMOS flip-flop to the board at IC2, align the notch on the top of the IC with the notch on the board silkscreen. [] Solder the two 4N35 opto-isolators to the board at ISO1,ISO2, align the circle on the top of the ICs near the notch on the board silkscreen. [] Solder the two-pin header to the board at JP1. Install the jumper clip on the JP1 header. [] Solder the 4 pin connector to the board at CN1. [] Solder the miniature 3 pin connector to the board at CN2, the the holes should face the outside edge of the board. [] Verify that C10, the LEDs, the ICs, diodes, and transistor are oriented correctly with the white markings on the circuit board. [] Check all of the solder joints for good flow, retouch any cold joints. [] Clean the leftover solder flux from the bottom of the circuit board with rubbing alcohol. Use an old tooth brush to scrub the board then soak up the residue with a tissue. Repeat until the board is clean. [] The board assembly should now be complete.