High Current Digital Ouputs
Some devices draw a bit more current than a logic device can deliver
Things like
- relays
- solenoids
- lamps (annunciators)
- motors (on/off)
- and a lot more
can draw from a few milliamps to several Amperes of current. Driving those kinds of devices can be a hassle... Here is where the High Current Ouput Daughterboards come into play.
If your device draws less than 1A at less than 100V DC, you should be able to control it directly via the outputs of the high current daughterboards.
To power devices that need even more amps and/or require a higher voltage, as well as all AC based equipment, for example mains powered devices at 110V AC, 230V AC,... t hen you need to use a relay (which can be driven by the high current output daughterboards).
Available or planned PHCC High Current Output Daughterboards
DOB_74595+T
Features:
- 16 channels
- up to 1A per channel
- up to 80V
- optional back EMF diodes to prevent inductive loads (relays, solenoids, motors) from destroying the transistors and logic
- open collector outputs
- uses DOB protocol
- shift register based design
- daisy-chainable
- optional on-board DOB line amplifier (for daisy-chained boards)
Schematic and Layout
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Bill of Materials
The BOM is here: PHCC_DOB_74595+T.BOM.txt
This list includes prices and links to to online catalogue pages of my primary source of electronics components, Reichelt Elektronik
DOA_40DO
Features:
- 40 channels
- up to 125mA per channel (continous)
- up to 50V
- open collector outputs (sinking action)
- uses DOA protocol
Schematic and Layout
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| Click to enlarge [99k, 1362x1015] |
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A note to DIYers
This board is so far one of the hardest for DIY. Lots of thin traces with spacings of often just 8mils. In addition, several wire bridges (for single-sided boards) / top side traces (for double-sided boards) are very close to IC pads. These facts make this particular board a challenge for people who are not regularly etching PCBs at home. For details, go ask on the PHCC forum.
Bill of Materials
see download page.
Eagle and Gerber files
see download page.
