Datasheet

PedalSync™

Tru-Foot

LFO chip MV-55(B)

Datasheet - p.9

PedalSync_MV-55_MV-55B_Tru-Foot_LFO_Datasheet.doc DRAFT v9.1

Electrical Considerations

9 volts DC maximum on the power input to the module.

At least 7.5 volts input.

The schematic below shows the necessary, as well as optional, connections. Note that you can use

different resistors for the LEDs depending on the type of LED used, but do not exceed the current

limits of the underlying chip as set forth below.

If you require brighter LEDs, consider using buffers or ultra-bright LEDs.

The datasheet for the underlying dsPIC33FJ64GP802 chip can be found here:

http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en532310

If more than one circuit will be controlled by the LFO, be certain to buffer the output (e.g. with op amp

followers) to ensure a consistent output signal to each circuit.

Noise

It is very important to properly filter your power supply as shown in the schematic.

To minimize digital noise bleeding into your audio circuit, be careful to run three separate grounds as

indicated on the schematic.

Follow proper PCB layout design rules and isolate the digital and analog sections of your circuit as

much as possible, connecting the grounds at a common point at the power supply.

The Ferrite on AVDD may not be totally necessary but will quiet down and stabilize the analog

voltage. Thru hole values for ferrites are limited and may not be available beyond 800 ohms. The

recommended part which appears on the Tru-Foot LFO Module is a 2.5 KOhm Impedance 50mA

Ferrite, such as Murata P/N BLM18BD252SN1D.