The Mean Well EPP-300, RPS-300, EPP-400, and RPS-400 models are excellent switching power supply choices for an LM3886-based power amplifier. However, as these supplies have only one output, they must be configured properly for use as a dual or split supply. In addition, the Mean Well supplies feature low-voltage on/off control, thus, need a little bit of digital logic to interface to a regular power switch and 12 V trigger.
The Mean Well Control features:
- Easy connection to two Mean Well EPP/RPS 300/400 series power supplies creating a dual supply suitable for audio amplifiers.
- Remote sensing eliminates the voltage drops across connecting wires and PCB layout, thereby minimizing the output impedance of the power supply.
- Power output provided on Molex Mega-Fit and industry standard JST VH-series connectors for easy connection to the Neurochrome Modulus and LM3886DR amplifiers.
- Easy connection to a momentary power switch, such as the many anti-vandal switches popular in DIY audio circles.
- Support for both two-pin bi-colour and regular LEDs for ON/STANDBY indication.
- Optically isolated 12 V trigger input.
- Optical isolation between the control signals for the two Mean Well supplies to minimize any coupling between the supplies.
- Six-pin header connector allowing for connection to protection circuits, signal-detect circuits, etc.
- Elaborate use of copper planes and pours to ensure the best circuit performance.
- 4.00 × 1.75 inch board footprint. The finished module measures approx. 20 mm in height.
The Mean Well Control prototype build is shown below. The final revision of the PCB is expected in stock towards the end of August.