sympleSEQ 5V Level Conversion

Convert your sympleSEQ v1.0 to standard TTL 5V levels using this handy guide!

This will make your sympleSEQ fully compatible with seqSQUARED when it comes out!



Gate Level Conversion

Use a standard LM7805 voltage regulator to convert your gate signal to a 5V "on" level. You can use the small version that's the same size as a standard through-hole transistor. Since the current you are regulating with the 7805 is so low (just a gate signal), you probably don't need a .1uF smoothing cap on the in/output of the 7805.

The same thing can be accomplished with a Zener diode regulating circuit, but I actually consider the 7805 easier to wire...it's just in, out and ground, whereas the Zener setup needs a resistor as well.
Clock Input Level Conversion

Since sympleSEQ requires a positive clock pulse close to the supply voltage you are using for sympleSEQ, you may find it difficult to clock it with a standard 5V level signal as present in many modular setups.

This solution should be simple enough for most to implement.

Since sympleSEQ already has spare 40106 inverter gates on the logic board, all that is necessary for you to add in are a standard NPN transistor (2N3904, etc.) and some resistors.

To gain access to the spare inverter that occupies pins 10 and 11 of IC1 on the sympleSEQ logic board, you must cut the PCB trace which connects pin 3 to ground. This will unground the unused input and allow you to use it for this modification.

Now, just solder to the pins underneath the sympleSEQ logic board to get connection to your inverter!

The value of R1 is not horribly important. Any resistor value from about 1k to 3.5k should work, so feel free to use whatever you have around!
CV Output Conversion

To reduce your CV levels to something more usable in a volts-per-octave environment, a very standard voltage division circuit can be placed on sympleSEQs CV output. This will limit the maximum voltage a CV knob gives to 5V, giving you 5 octaves of pitch and levels that are fully compatible with pretty much all other modular gear.

Make sure to use the resistor values I've calculated for your supply voltage level, or you risk outputting too high (or low) of a voltage!