which low voltage portable IC amplifier

[tschrama]

Hi all,

I hope one of you guys can help me. I need to build a protable amplifier, battery powered, about 4 watt maximum output power.

For this I selected to use 6 x 1.5Volt pentlite batteries and the TDA7266 IC amplifier. However, I cann't seem to buy this IC in my country (The Netherlands).

Can someone suggest another IC?

It needs to run on low-voltage (from about 6.5 volts), and must not drain the batteries, so low Iq), and prefferebly drive the 8 Ohm load in bridge mode.

Greetings from The Netherlands,

Thijs

[jackinnj]

there are a lot of amps to suit your needs -- go to the Nat Semi website and enter "Boomer" into the search engine -- follow the link to the parametric search engine -- you should be able to get samples in the Netherlands.

http://cache.national.com/ds/LM/LM4663.pdf

[tschrama]

Hi Jackini,

Thx for your suggestion. I noticed however that the Nat Semi IC seem to be suited either for 5.5Volts max or 10Volt minimum (1 exception).. which is just the area I looking for.

I have looked into 39 different IC now, from Philips, ST electronics and Nat Semi, I cann't seem to find a really nice one.

It should be that difficult, 7.5 V min, be able to drive 4 Ohm or 8 Ohm bridged and give about 4 Watts...

[tschrama]

Anybody knows a source for the TDA7266 or TDA7267? Anyone know an equivalent for such a chip? (6-12 Volt, bridged audio IC amp)..


greetz,
Thijs

[Nisbeth]

Reichelt have them both as far as I can see


/U.

[tschrama]

Thx... I tried to order them, but I need a 100Euro minimum order

I think I have found a dealer for the TDA7266-ST, now I need to find the datasheet of this particular version...

Regards,
Thijs

[cunningham]

I'm not too familiar with TDA7266, but LM386 is perfect for your application. It is a DIP 8-pin package.

I remember long ago when I was in high school I made a portable battery amp using two of them. I used a small input audio transformer as a phase splitter, with a dual op-amp chip as a pre-amp for each LM386 chip and bridged the outputs of each LM386 chip, 100uF coupling capacitor, across 8Ohms. This drove them a little hot, so I put a small IC heatsink on them. This was probably the simplest design that I have made that worked so well. It put out 5-8 Watts cleanly.

Sometimes simple is just better.

[jackinnj]

Originally posted by cunningham
I'm not too familiar with TDA7266, but LM386 is perfect for your application. It is a DIP 8-pin package.

I remember long ago when I was in high school I made a portable battery amp using two of them. I used a small input audio transformer as a phase splitter, with a dual op-amp chip as a pre-amp for each LM386 chip and bridged the outputs of each LM386 chip, 100uF coupling capacitor, across 8Ohms. This drove them a little hot, so I put a small IC heatsink on them. This was probably the simplest design that I have made that worked so well. It put out 5-8 Watts cleanly.

Sometimes simple is just better.

the LM386 is a bad-sounding chip -- even ham radio ops complain about it (although widely used.)

[cunningham]

You have to add filters to even out the gain/bandwidth in order to correct the not so good slew rate of this chip, that is usually what makes it sound crappy. Also if you are talking full range, this is a major problem.

[tschrama]

Thanks for the tip.. I will look-up the LM386. It's for bird-playback-experiments; the particular birds only call at 350-650Hz. The goall is to get rid of my oversized, 10Kg heavy equipment and built something more portable, yet reliable and up for the task.

gr,
Thijs