Lpc2000

>> I'm currently experimenting with a MAX1684 for the main circuit (<150
>> mA, 100 mA typical when full active) and a linear regulator (LM317)
>> for the radiomodem (<5mA typical 98.3% of the time, 160~200mA average
>> 1.6% of the time). I'm trying to trick the LM317 with large R1-R2
>> values (~8KÙ) to keep power consumption low. The radiomodem will work

Careful there. Most versions of the 317 won't maintain regulation without a
minimum load, so check the data sheet carefully. We just brought up a new
design where the tech misread the schematics, used setpoint resistors which
ere too high, and the result was the 317 output was equal to the input (30V=
)
due to too-low output current, and this smoked some 3.3V parts on the outpu=
t.

Also before you design in Maxim, be sure you can really get them, and there=
 is
a second source if possible. Maxim has a history of long and/or unpredictab=
le
lead times - we are periodically bitten by this. Some Maxim parts have uniq=
ue
functions which we need, but it's frustrating...

Linear Technology has some great, non-commodity regulators which we use in
quantity. Efficiencies are good, support is good, and so is availability.

Regards

Bruce