Regulators needed

[dbemowsk]

So I was working on building myself a new serial gateway tonight when I realized that I am out of 3.3v TO-92 package regulators. I have some AMS1117 3.3v regulators, but they are in an SMT package making mounting them to a thru hole regulator near impossible. I figured since I need to buy more, I will go with LDO regulators. Are there any that perform better than others? Are there any things I should be watching out for? Is there a good place to buy them cheap where I can get them in a pack of 20 or so to stock up?

[gohan]

The most common ldo I saw are le33 and mcp1700

[NeverDie]

It's a good question, and it deserves a good answer. Since a gateway will probably be mains powered, rather than battery powered, I'm guessing that an LDO with less ripple and/or more noise rejection might improve the range/coverage of the gateway. i.e. just slapping in the cheapest, most common chips might be self defeating. That's too vague an answer though, and I'm sorry I can't do better. Has anyone looked into that angle?

[dbemowsk]

@neverdie Good points though.

[dbemowsk]

Another one that seems promising is the LP2950 series. Just wondering if anyone has had any experience with these?

[Nca78]

@dbemowsk said in Regulators needed:

LP2950

Did you try them in the end or did you chose another one ?

I didn't know about those, they seem very nice if your node needs low current and you have a high input voltage, the max 30V is really nice for nodes like a led dimmer up to 24V.

[dbemowsk]

@nca78 I did go with those and it seems to be working great.

[heinzv]

@dbemowsk said in Regulators needed:

LP2950

I will use the AP2112K 3v3
https://www.diodes.com/assets/Datasheets/AP2112.pdf

it has overall very good values, 600mA output current, high effciency. I would not use the AMS1117 for battery usage.
It is also used by the excellent Adafruit Feather:
https://www.kiwi-electronics.nl/adafruit-feather-m0-wifi-atsamd21-atwinc1500?lang=en

Output Voltage Accuracy: ±1.5%
Output Current: 600mA (Min.)
Foldback Short Current Protection: 50mA
Enable Function to Turn ON/OFF VOUT
Low Dropout Voltage (3.3V): 250mV (Typ.) IOUT = 600mA
Excellent Load Regulation: 0.2%/A (Typ.)
Excellent Line Regulation: 0.02%/V (Typ.)
Low Quiescent Current: 55μA (Typ.)
Low Standby Current: 0.01μA (Typ.)

[cabat]

@dbemowsk
I used LP2950-5.0 in one node when feeding from 12v - about 3 months everything works quite stably.