LDR3x Current Draw

0 Members and 1 Guest are viewing this topic. Read 1144 times.

tortugaranger

  • Facilitator
  • Posts: 1746
  • Handcrafted high performance audio
    • Tortuga Audio
LDR3x Current Draw
« on: 22 Feb 2014, 02:21 pm »
I was recently asked about the current draw of the LDR3x Preamp Controller Board. It's been a while since I checked that so I just tested it. It's lower than I recalled. The readings were taken at power input with 12 VDC supply using precision 0.47 ohm resistor. See results below.

20 ma - LDR3x by itself
30 ma - with single DM1 display module at modest intensity
60 ma - with single DM1 display moduel at max intensity
90 ma - with max DM1 plus LED @ 5 volts without current limiting resistor

Since it's unlikely that you'd run both the DM1 and LED at max at the same time, the 90 ma case is probably unrealistically high.

The on board LM7805 regulator that provides 5 V is not heat sinked and runs cool to the touch which makes sense given the low draw even with the 7 volt differential.

As a practical matter, most any power supply between 100-500 ma will be more than adequate