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Electronics => Projects, Designs, and Technical Stuff => Topic started by: onesixright on January 04, 2017, 08:15:24 pm

Title: Shift register for driving 20 x reed relays (SIP-1A05)?
Post by: onesixright on January 04, 2017, 08:15:24 pm
Hiya All,

Lets start with best wishes, that all may happen what you wish for and that in good health!  :-+

Quick question. I need to drive 20 reed relays (SIP-1A05). I was thinking of using 3 x 74HC595, but that leaves me with a few pins not used. Not a big issue, but I rather have 1 component that has 20 (or 2x 10), and on top i prefer to drive it via I2C

Any thoughts?

Much obliged!
Title: Re: Shift register for driving 20 x reed relays (SIP-1A05)?
Post by: rstofer on January 04, 2017, 09:14:08 pm
Sure!  A couple of MCP23017 I/O Expanders ought to do it
http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf (http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf)