question about 3.3 volt regulator

[reyge]

ba033 3.3 volt regulator

Hello!

I just bought two BA033 to supply voltage to an IC. Unfortunately, the one bought for me was the TO252-3 package which has very small pins knowing that i am going to put it first in a breadboard. So, I had to solder wires for the 3 pins(not my best skill but see to it that the wires were shorted with the pins by using a multimeter). When I was already testing the regulator, I do not get the 3.3 volt output! I varied my input from 6 to 8 volts but the output is just a voltage slightly lower than the input. I tried the other BA033 and still got the same result. What could possibly be wrong with what I have done? Are there special considerations in handling this regulator?

I could really use some help. Thanks! Attached is the datasheet I researched from the internet

 

[pakitos]

Did you do the testing with the shortings removed?
please clarify your question

 

[vijaya_narayana]

try out the application diagram in the pdf document

 

[reyge]

oh.. what i meant by
"(not my best skill but see to it that the wires were shorted with the pins by using a multimeter)"
is that i see to it that i properly soldered the wires to the pins.

The ground pin is really small for the alligator clip that i have so really had to solder it. But i have tried testing the regulator without soldering additional wires for the VCC and OUT.

My primary question is, is there any special considerations when handling this regulator?

Added after 50 minutes:

[qoute]
try out the application diagram in the pdf document
[/qoute]

In my first try, i simply put a DC voltage in the VCC and then checked the output.

I tried a configuration suggested in the IC that i meant to connect with the 3.3 volts regulator, it is just composed of capacitors connected to the VCC and OUT pins. I got a voltage reading at the output that is smaller but still bigger than 3.3 volts

Either of the configuration should work right? The oscillators were just there to prevent oscillations and I do not have to put a load since it is a regulator.

Thanks

I implemented the configuration in Figure 5 in the datasheet but .3uF instead of .33uF and 23.5 uF instead of 22uF but still got the same result

 

[Lucifre]

what are the three letter at the end of the regulator?
i see that BAXX regulators have two series named BAXXCCOT or BAXXCCOFP
no significat difference but the BAXXCCOFP series have N.C in pin 2 meaning that there is no connection. Where as in BAXXCCOT sereis, pin 2 is ground. In any case, try using the fin (metal plate connected to ic) instead of pin 2 as your ground. Check if you are installing voltage regulator correctly (not applying vin to vout)
if all else fails use a new one, it may be fried.

 

[reyge]

what are the three letter at the end of the regulator?
i see that BAXX regulators have two series named BAXXCCOT or BAXXCCOFP
no significat difference but the BAXXCCOFP series have N.C in pin 2 meaning that there is no connection. Where as in BAXXCCOT sereis, pin 2 is ground.

The odd thing is there are no three letters after the BA033... A number 43 is printed near pin 1 and 80 near pin 3. Do you know what those numbers mean? Or are they significant? hehe

In any case, try using the fin (metal plate connected to ic) instead of pin 2 as your ground. Check if you are installing voltage regulator correctly (not applying vin to vout)
if all else fails use a new one, it may be fried.

In one of the regulator, I actually tried reversing the pins (applying vin to vout) but still got the same result.
When does a voltage regulator become fried? Does reversing the pins fry it? Can ESD fry it?

Thanks!

 

[nguyennam]

The part you got is really BA033FP. The "FP" letters are omitted on package since it is for TO-252 package. The others digits you see are just the manufacturer's codes for wafer lot / factory place / date of manufacturing ... which in turn are not your concern.

Suppose you are badly skilled in soldering, although TO-252 is not really small for an amateur, so you might kill the first part, but for the second one, you might not since your skill was improved from the first one !!!.

Just use your DMM in "ohm range" or "diode test range" to measure the resistance between input and output pins in 2 ways of applying test leads, if the resistances are small and almost equal, so the part must be dead. If the resistances are large (a few hundred kiloohm or megohm), so maybe part is good.

The datasheet you get is not in details, so I do not understand if it needs the minimum load (many voltage regulators need the minimum loads other than 0 (open output) to work well). Try to put at output pin a resistor of about 330 ... 620 ohm to make the minimum load (5... 10mA) to regulator and then measure the output voltage.

 

[reyge]

Nevermind.. I still did not make it work or perhaps the regulator is really fried from the start. What I did was just use a 5 volt regulator, then connect the output to 3 diodes in series and got a steady voltage of around 3.2 volts which was enough to turn on my IC..

Thanks anyway for the replies. ^_^

 

[funnynypd]

Nevermind.. I still did not make it work or perhaps the regulator is really fried from the start. What I did was just use a 5 volt regulator, then connect the output to 3 diodes in series and got a steady voltage of around 3.2 volts which was enough to turn on my IC..

Thanks anyway for the replies. ^_^

When your circuit is working, did you get high temperature on your diode?

 

[reyge]

When your circuit is working, did you get high temperature on your diode?

No, i did not. Why?

 

[funnynypd]

The diode usually are very strong, though it can be damaged by long-time overheat. Sometime you can even see a explosive site on the package.