Re: [Autopilot] Power regulators and RS-232 line drivers

[Tramm H. <hu...@sw...>]

Martin Spott wrote:
> There are LM317 in a very small package - as large as a simple transistor.

I read that the LM317 and LM7805 require at least 2.5V greater input
than the output.  So for a 5V regulator supply we would require a 7.5V
input, except that our batteries are only four cell (4.8V when
fully charged).

So how would we use them?  Or should we just put a capacitor across
the power input to smooth out the servo noise?  The ADXL, MG100 and AVR
are all tolerant of voltage swings and can deal with +2.5 to +5.25V
inputs.

> I used them for a selfmade radio clock receiver (with a MAX232C os so
> serial driver),

I went ahead and used the MAX202 chip that the STK300 uses.  Only
because I have a schematic and board with it that work.  You can
see it in the latest schematic online.  Is there any reason to use
the MAX232 instead?

Trammell
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