CirKits.com BVM1-a1 Battery Voltage Monitor Assembly Instructions Instructions Rev: May 10, 2013 Check http://www.cirkits.com/bvm1 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 BVM1 circuit board on http://www.cirkits.com/bvm1/ 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 fine gauge flat screwdriver for circuit adjustment digital 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. [] Insert one 750 ohm (violet green brown) resistor at R6. [] Insert one 820 ohm (gray red brown) resistor at R5. [] Insert one 1.5K ohm (brown green red) resistor at R4. [] Insert one 8.2K ohm (gray red red) resistor at R3. [] Insert one 12K ohm (brown red orange) resistor at R8. [] Insert three 10K (brown black orange) resistors:R7,R14,R15. [] Insert five 100K (brown black yellow) resistors:R1,R10,R11,R12,R13. [] Insert two 2M (red black green) resistors:R2,R9. [] Solder one 2.2nF capacitor (marked 222 or .0022uF) to the board at C5. [] Solder one 10nF capacitor (marked 103 or 0.01uF) to the board at C4. [] Solder two 100nF capacitors (marked 104 or 0.1uF) to the board at C1,C3. [] Solder one 1uF capacitor (marked 105 or 1uF) to the board at C2. [] Install the black 1N5818 Schottky diode at D1. The white band on the diode should line up with the circuit board marking. [] Install the small glass 1N4148 diode at D2. The black band on the diode should line up with the circuit board marking. [] Solder the 78L05 regulator to the board at IC4. Align the flat side of the regulator with the board marking. [] Solder the 2N7000 MOSFET transistor, to the board at Q1. Align the flat side of the transistor with the board marking. [] Solder the small green picofuse to the board at F1. [] Solder the two SPDT switches to the board at S1 and S2. For flush-mounting to a panel, the switches can be installed on the back side of the board, along with the 10 LEDs. [] Solder VR1, the 2K potentiometer (marked W202), to the board. The adjustment screw should align with the circle in the solder mask. [] Solder VR2, the 1K potentiometer (marked W102), to the board. The adjustment screw should align with the circle in the solder mask. [] Solder VR3, the 10K potentiometer (marked W103), to the board. The adjustment screw should align with the circle in the solder mask. [] Solder IC1, the LMC555CP timer IC to the board, pin 1 on the IC is marked with a small circle indentation. Pin 1 goes near R2. [] Solder IC2, the LM3914N volt meter IC to the board, align the semicircular indentation on the top of the IC with the board marking. [] Solder IC3, the TLC2272CP dual R2R op-amp to the board, pin 1 on the IC is marked with a small circle indentation. Pin 1 goes near R7. [] Solder the 2 pin connector to the board, the wire holes should point toward the outside of the board. [] Separate the 10 LEDs into 5 sets of two colors each. The white LEDs have a yellow-white blob of phosphor that is visible from the top. The amber LEDs are made with amber tinted plastic. The color of the other LEDs are marked on the LED wire leads with ink. For flush-mounting to a panel, the LEDs may be installed on the bottom of the board, along with the two switches. The flat side of the LEDs should line up with the board markings, the longer lead goes toward the round side of the markings. Be careful not to overheat the LEDs when soldering, they can be damaged by excess heat. [] Solder the two red LEDs into the board at LED1 and LED2. [] Solder the two amber LEDs into the board at LED3 and LED4. [] Solder the two green LEDs into the board at LED5 and LED6. [] Solder the two blue LEDs into the board at LED7 and LED8. [] Solder the two white LEDs into the board at LED9 and LED10. [] Press the black round piezo speaker PZ1 firmly into the board and solder the two pins. [] Verify that the LEDs, the ICs, diodes, and transistor are oriented correctly with the white markings on the circuit board. [] Visually check all of the solder joints under a magnifying glass, retouch any cold solder 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 or paper towel. Repeat until the board is clean. [] The board assembly should now be complete.