I'm designing a transmit/receive switch for an antenna using a PIN diode.

The PIN diode I'm using is UM7512 make: Microsemi.

I need to switch between -400V (off) to +5V (on). The switching time should be 50usec.

On current is 200mA. Off current is 1-2 mA.

I need a reference circuit idea or design about this requirement.

How do I approach this design?

  • \$\begingroup\$ By first realizing how much capacitance you have to drive? \$\endgroup\$
    – jonk
    Commented Aug 7, 2020 at 18:17

1 Answer 1


The schematic contains the PIN diode approx. DC model, there are no high frequency components on it. The 2mA from the -400V can be set by R3. pindiodeoff

The 200mA PIN diode forward current is set by R1. pindiodeon

DC Transfer Characteristic: pindiodetrans

The switching times are set by L1. pindiodetranzient

If the 5V isn't enough to PIN diode forward current, the power supply voltage of U1 can be increased up to 18V. But afterwards you have to set R1 for the 200mA again. The input voltage remains TTL and 5/3V CMOS compatible at every power supply voltage (U1).

  • \$\begingroup\$ Thank you so much. I'll try this one. \$\endgroup\$
    – Aparna B
    Commented Aug 10, 2020 at 2:03
  • \$\begingroup\$ may I know the simulator you have used to simulate this. \$\endgroup\$
    – Aparna B
    Commented Aug 10, 2020 at 2:13
  • \$\begingroup\$ I've used for this the simulator from TI (TINA-TI). \$\endgroup\$
    – csabahu
    Commented Aug 10, 2020 at 6:35
  • \$\begingroup\$ Can I get your Tina file for this circuit so that I can simulate on my computer? \$\endgroup\$
    – Aparna B
    Commented Aug 10, 2020 at 14:01
  • 1
    \$\begingroup\$ You can find the Tina files here in the pin sw.zip folder. Select the component with a left click and then right click to see the macro (component spice model). \$\endgroup\$
    – csabahu
    Commented Aug 10, 2020 at 18:12

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