LM4780 HiFi Stereo Amp NEW VERSION 1.4.0 x 60W RMS PCB DIY


This listing is for a well-designed PCB for building a high quality stereo power amplifier based around the excellent LM4780 IC, priced at only £4.99.

PCB ONLY. NO COMPONENTS.

CLEARANCE SALE - NOW REDUCED TO 1.99GBP

(Soon to be superseded by our new LM4766 board).

We are now up to  version 1.4.0. Facility for RCA connectors has been added, but you can still use a terminal block for input connections if you wish. 

We have sold hundreds of these great little boards to very satisfied customers - ask around on the forums!

For a very low outlay indeed you will end up with a superb sounding piece of hi-fi equipment equal in audio quality to off the shelf amplifiers costing hundreds of pounds. 

This amp is perfect for building a hi-fi system, boosting the sound on your TV, or for building self-powered speakers, plus much more.

Features:
• Two sided PCB with heavy 2 ounce traces (designed in the UK).
• Extra wide traces for power and output signal paths.
• Star signal ground paths to eliminate ground loops.
• Screw terminal blocks for all wires (optional).
• Extensive capacitive filtering for minimum hum/distortion.
• Soft-start feature to avoid sudden high volume on power up.
• Compact size only 95mm x 65mm.
• Convenient 4mm mounting holes on each corner of the pcb.

With the addition of a few extra components, it is possible to wire in parallel for 120W mono solution. 


BOM and build instructions are supplied.

Obviously you will need an LM4780 chip can be bought on eBay.
You will also need:

  • 3 x Resistor 15k 5% ¼W for Rin1, Rin2, RM2 
  • 4 x Resistor 1k 1% ¼W for RB1, RB2, Ri1, Ri2 
  • 2 x Resistor 20k 1% ¼W for Rf1, Rf2 
  • 3 x Resistor 2.7Ω 5% 1W for RSN1, RSN2, Rg 
  • 1 x 10k Resistor for RM1 
  • 2 x 1uF 10% Metallised Polyester for Cin1, Cin2 
  • 2 x 68uF 50V Electrolytic Radial for Ci1, Ci2 
  • 5 x 100nF 20% Monolithic ceramic for Csn1, Csn2, Cs1, Cs2, Cs3
  • 2 x 15pF 20% Monolithic ceramic for Cn1, Cn2
  • 4 x 10uF 20% Electrolytic Radial for Cs4, Cs5, Cs6, Cs9
  • 2 x 1000uF Electrolytic Radial for Cs7, Cs8
  • 2 x 2 way 5mm terminal block (optional, can solder wires directly to pcb)
  • 2 x 3 way 5mm terminal block (optional, can solder wires directly to pcb)
  • 4 x 4mm nylon self-adhesive mounting posts (optional)
  • A decent heat sink is advised.


You will need a soldering iron and basic soldering skills.

Finally, you will need a dual unregulated DC power supply of between 2x20V to 2x35V driven by an 80VA transformer. We sell a PCB for building such a power supply for only £3.99, please see our other items.

Maximum output power is dependent on the power supply voltage. A ±20 volt supply would be adequate for most systems giving providing between 25 and 30 Watts/channel into an 8 Ohm load (35 - 40 W into 4 Ohms). 
CAUTION: Although voltage dependent components on the PCB are rated at 50 volts, we do not recommend exceeding ±35 volt power supply.
Note regarding amplifier power The LM4780 is rated at up to 60 watts per channel. 

For those who haven't heard of the LM4780, it is the latest offering from National Semiconductor. It features two 60w channels into 8Ω or 120w in mono. It has a very low noise level of 114db at 50W RMS and an astonishingly low THD of 0.03%. It is actually two LM3886 ICs built into a single casing. If you're a person who likes power AND quality in their music, this is for you!

Download the LM4780 datasheet here: http://www.ti.com/lit/ds/symlink/lm4780.pdf

This PCB circuit is very similar to the reference circuit in the datasheet.

To summarise, these are PCBs for constructing a high quality power amplifier very cheaply. No components are included, but they are VERY easy to source. 

Please note, although a fully built unit is shown in the listing picture, it is for illustration only and not included.

The price is only £4.99 Buy it Now.

POSTAGE & PACKING:
£1.49 to the UK NO MATTER HOW MANY YOU BUY.
£2.99 rest of world NO MATTER HOW MANY YOU BUY.

Please check out our other items.