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dimmer

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Building up a Dimmer

Please note that this dimmer is for CLF lamp power supplies only that support 1-10V input (Osram DIM interface) as described on the homepage. It is not for connecting lamps directly to it.

Needed Parts and PCB

You need a PCB. You may use the layout from Github and etch it yourself or order the PCB or a complete kit.

Partlist (in buildup order)

Amount Part Placing Picture
1 PCB Dimmer pcb_dimmer.jpg
6 Diode 1N4148 D1-D6 diode_1n4148.jpg
1 Resistor 680R blue-gray-brown R1 resistor_680r.jpg
2 Resistor 1k brown-black-red R2, R6 resistor_1k.jpg
1 Resistor 1M brown-black-green R4 resistor_1m.jpg
1 Resistor 1k3 0,1% brown-orange-black-brown R3 resistor_1k3_0p1.jpg
1 Resistor 100R 0,1% brown-black-black-black R5 resistor_100r_0p1.jpg
1 IC holder IC1 ic_holder.jpg
1 Voltage regulator 7812L IC3 ic_7812l.jpg
1 Voltage regulator LP2950Z IC4 ic_lp2950z.jpg
2 Transistor BC547C T1, T2 transistor_bc547c.jpg
1 LED 2mA LED1 led_yellow.jpg
1 Connector AVR ISP 6pin angled JP1 connector_isp_angled.jpg
3 Connector 2pin X1, X2, X3 connector_clamp_2pin.jpg
1 Connector 1 pin header (for serial TX debugging) JP2, JP3 connector_pinheader.jpg
2 Capacitor 10µF C1, C4 capacitor_10uf.jpg
2 Capacitor 100µF C2, C3 capacitor_100uf.jpg
1 IC ATMega328 IC1 atmega.jpg
1 Fuse holder F1 fuse_holder.jpg
1 Fuse 50mA T F1 fuse.jpg
1 Relay G5LE (12V) K1 relay_g5le.jpg
1 Transformer 12V TR1 transformer_12v.jpg
1 Transceiver PCB RFM12B IC2 ic_rfm12b.jpg
1 Antenna (82,2mm wire) antenna.jpg

Buildup of PCB

As always: start from flat to high. Go through the partlist and solder the parts from the top ones to the last ones.

For some parts, you have to consider something special:

  • IC holder: Look at the notch and place it in the right direction.
  • LED: Solder it to a wire if you want to place the PCB in a housing later. Read the instructions on how to solder the LED to a cable. The longer wire of the LED is +. It goes into the hole more in the middle of the PCB.
  • ISP Connector: The notch points to the side of the PCB (towards the voltage regulator).
  • Capacitors: The marked line is -. On the PCB, + is labelled.
  • ATMega: Before inserting it, you may want to check the voltage levels when switching the power on. Pin7 should have VCC (3.3V) against pin8 (ground). If you have different voltages: don't panic, nothing is broken, nothing is fried. Search your error. To insert the ATMega, bend the pins at 90 degreed by placing the ATMega on the table and bending it carefully. Then insert it into the IC holder. Be sure that you are not charged with electricity (ESD!) when touching the IC pins.
  • RFM12B: You should also check the voltages first before soldering the module. At the place for the radio module the pad beside the antenna and at the opposite side the third pad should read about 3.3 V. For soldering, read the RFM12B mounting instructions.

(Image directly loaded from external GitHub source. If it doesn't work, fix link in wiki!)

Bringing the device into operation

Don't power the circuit immediately by the 230V transformer. It is highly recommended to first connect a DC power supply to JP2 at 14.5 to 20V. You can then safely set up and test everything without using dangerous high voltages.

Flashing the firmware

If you have a new ATMega where nothing is flashed onto, download a prebuilt binary package or build your own firmware. If you bought a hardware kit, the ATMega should already be flashed.

After flashing and switching the power on, the LED flashes several times. The relay stays off. If you switch the dimmer on with a switch at JP4 (near the LED), the relay should switch on.

Integrate it into a housing

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dimmer.1401547136.txt.gz · Last modified: 2014/05/31 16:38 by breaker27