I'm working on a circuit for an ultra-low power microcontroller and two configurations are given for RFO HP and LP to operate in low and high power modes respectively. I tracked down an application note for using both and they recommended using DC switches (or solder bridges for a static configuration) and presented the diagram below.

The reference.

The design already includes this load switch and I was hoping to find something similar but for toggling a connection instead of interrupting it. The image below shows my ideal solution.

What I want

I have been searching for a similar ultra-low power IC but haven't even been able to find any SPDT switches, let alone DPDT.

Does this device (or another low power solution) exist?

  • 1
    \$\begingroup\$ Typically this would be done with distinct switches, especially as most of the time you may not want to have either on. What's the transmit current? Typically the switch's active power is nothing compared to the transmitter, it's whatever load it presents when not active which would be a concern. An FET is fairly good in both respects though... \$\endgroup\$ Sep 22 '20 at 16:10
  • \$\begingroup\$ Some parts are available with both control input polarity possibilities, so you could run a pair of those with a single signal if you really aren't interested in a "both off" case. \$\endgroup\$ Sep 22 '20 at 16:12
  • \$\begingroup\$ Sadly lacking in details: voltage switching levels, current switching levels, control voltages, tolerable leakage currents? \$\endgroup\$
    – Andy aka
    Sep 22 '20 at 16:28
  • \$\begingroup\$ How often do the switches have to change position? If it's very rare, then a latching relay might be worth considering. \$\endgroup\$
    – The Photon
    Sep 22 '20 at 16:35
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    \$\begingroup\$ Have you looked at SPDT multiplexers? \$\endgroup\$
    – Andy aka
    Sep 22 '20 at 17:10

Voltage levels would be no more than 3.3V, Current less than 150mA non-continuously, Control voltages also 3.3V and leakage as low as possible.

What does "as low as possible" mean numerically?

Preferably less than 2-3 μA

Something like this maybe: -

enter image description here

Pick your own from this selector page. Choose (2:1)x2 for device configuration to enable the choices.

Maxim and TI will have similar offerings.

  • \$\begingroup\$ That looks perfect, thank you. I thought I was going crazy trying to find this going through filters to search for this and thinking "surely this exists". \$\endgroup\$ Sep 22 '20 at 17:16
  • \$\begingroup\$ Leakage for that device is really low too. Maybe a tad expensive from ADI but you get what you pay for. TI might be cheaper. \$\endgroup\$
    – Andy aka
    Sep 22 '20 at 17:18

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