HeaterMeter 4.3 LCD Buttton Board Assembly
The HeaterMeter v4.3 LCD Backpack PCB has two sides and components are placed on both. The silkscreen outlines indicate the component footprints where they should placed. As with the base board, the easiest way to assemble the board is to start with the flattest components and work your way to the larger pieces.
The bottom of the LCD board is the side opposite the side with the "HeaterMeter LCD Backpack" text on it, where the majority of the components will be placed.
| Qty | Value | Device | Parts |
|---|---|---|---|
| 2 | 220 | R-US_0204/7 | R12, R15 |
| 1 | 1k | R-US_0204/7 | R10 |
| 1 | 1k2 | R-US_0204/7 | R8 |
| 1 | 1k8 | R-US_0204/7 | R11 |
| 1 | 3k9 | R-US_0204/7 | R2 |
| 1 | 8k2 | R-US_0204/7 | R9 |
Step 1 All resistors. The orientation on these does not matter-- either lead can go in either hole, as long as the body of the resistor is on the right side of the board. The placements are sized such that you should be able to fold the leads of the resistor against the body at a right angle and have them just fit into the holes. It is fastest to insert a couple resistors at a time and flip the whole board over, resting the board on the resistors to hold them in place while you solder them and clip the extra leads off. Note: you will not find the R12 mark on the PCB but it is located right above the R10.
| Qty | Value | Device | Parts |
|---|---|---|---|
| 1 | 0.1u | C-US025-025X050 | C10 |
| 1 | 74HC595N | 74HC595N | IC3 |
| 1 | BS170 | BS170 | Q4 |
Step 2 Start with the Ceramic capacitor. This small yellow blob also has no polarity, so its orientation does not matter.
Install the 16 pin shift register into its footprint. This part has a notch on one side of them which indicates the direction it needs to be placed which matches the notch on the PCB silkscreen. It is easier to install if the legs of the IC are bent inward by pushing them sideways against the table before inserting. The final BS170 MOSFET can then be installed.
| Qty | Value | Device | Parts |
|---|---|---|---|
| 1 | LCD1M, LCD2M | 1X5 M | JP1, JP8 |
| 2 | LCD1F, LCD2F | PINHD-1X5 F | JP1, JP8 |
Step 3 Break off 2x 5-pin segments from the male pin header strip. To make an accurate snap, grip the pin header with needlenose pliers with exactly 5 pins exposed and bend the plastic pin carrier to break off the required number of pins. These pins should be installed such that the small end of the header is inserted into the bottom side of the board, so the longer pins will extend away from the board. To get these to be soldered straight, solder only one pin lightly. Then hold the board in your hand, with your finger on the header and touch the soldering iron to the one pin you've soldered. While the solder is hot, wiggle the pins to get them installed at a perfect right angle to the PCB. Once the pins are properly placed, solder the remaining pins first, and then go back and retouch the first pin to assure a good solder joint.
| Qty | Value | Device | Parts |
|---|---|---|---|
| 1 | 10k | POTENTIOMETER | R6 |
Step 4 The LCD Contrast potentiometer is unique in that it installs on both sides of the board, by straddling the PCB with its pins. Two pins go on the bottom (side all the components have been placed thus-far) and one on the top.
| Qty | Value | Device | Parts |
|---|---|---|---|
| 1 | LCD | NEWHAVENLCD | LCD |
| 1 | LCD | PINHD-1X16 M | J1 |
Step 5 Prepare the LCD for installation by soldering a 16-pin segment of male pinheader to the LCD. The pins should be inserted with the long ends down into the bottom left set of holes in the NewHaven PCB. After soldering the first pin, be certain the pins are perfectly vertical before soldering the remaining pins.
After soldering the pins to the LCD itself, solder them to the LCD/Button Board by inserting them from the bottom of the LCD/Button Board up through to the top and solder from this side. In this instance, be certain that the pinheader is flush against the LCD/Button Board before soldering all of the pins. There should be a sandwich looking down from the top (side with the buttons printed on it) which is: the LCD/Button Board, short end of the pin header, the plastic pinheader carrier, the long end of the pin header, and finally the LCD itself with your soldering on either side of this sandwich.
| Qty | Value | Device | Parts |
|---|---|---|---|
| 1 | BUTTONS | TACTILE-12MM | S1, S2, S3, S4 |
Step 6 Zomg buttons! Install the buttons on the opposite side of the board from the rest of the components. The buttons can be two different ways (rotated 180 degrees) so there is no wrong way to do it. Be careful when popping them in to not crimp/crush a leg under a body of the button or it will not lay flat on the board and the case won't close properly.
| Qty | Value | Device | Parts |
|---|---|---|---|
| 1 | RED,YEL,GRN | LED3MM | LED1, LED2, LED3 |
Step 7 The LEDs need to not be installed flush against the PCB or else they will be too short to be seen outside the case. The easiest way to install them at the right height is to put them into the PCB on the top side, with the longer led in the hole closest to the + mark on the PCB. Hold them in place and flip the board over and insert it onto your HeaterMeter case and align the LEDs with their holes. Once in place, solder them and clip the excess lead. Because the buttons stick out through the holes of the case, be sure to elevate it so the buttons don't cock the board at a weird angle. This can be done before the previous step to make it easier if you have the case on hand at that time.
The HeaterMeter LCD/Button Board can now be mated to the Base Board followed by a throwing of confetti. As there is no polarization key on the headers, be careful to not install the LCD/Button Board upside down and that all 5 male pins are engaged in their female sockets on both sides.
