Tuesday, 12 September 2017

TDA2030A & TDA2030 Amplifier Observations

TDA2030A & TDA2030 Amplifier Observations - Intro


I have recently built portable battery powered speakers using a PAM8403 and a PAM8610. They are very efficient "Class D" amplifiers and can be run on high volume for hours and hours on one set of AA batteries (1.3ah).

However, I would like more bass! So I have tried this TDA2030A "Class AB" board to see how it compares. The TDA2030A is almost identical to the TDA2030. The former have a slightly higher max wattage rating.

This amplifier can be built on to boards that can handle up to 22V although 36V is achievable in some applications. I was limited to 16V by the capacitors that were installed on my pre built board, purchased from ebay (fluxworkshop).



TDA2030A & TDA2030 Amplifier Observations - Current


This is perhaps the TDA2030A amps most troubling characteristic. It requires 3.5A of current (max current), this means that with anything other than top end AA batteries such as "Eneloop" you will not be able to run this on AA batteries. They would also drain quickly even if you could!

The limiting factor it appears with the use of AA cells is the battery holder box. After testing one of the springs had melted and slumped.. I have read elsewhere that the cheap AA battery holders are only good up to about 1.5A.

So . .  you will need a power supply from the mains. . .or lithium high drain cells or an SLA Battery. Again the battery holder for the lithium cells will have to be good quality.

By comparison the PAM8403 and a PAM8610 draw about 1.0A of current which is ideal for use with AA batteries and cheap holders.

I tried the following batteries:


  1. 6 x AA 1.3ah Uniross Batteries in Holders - Not Good
  2. 5 x 4.5ah NiMh (Battery Pack from Silva Headtorch) - OK
  3. 1 x 12V SLA (Actually LiPO4 but in SLA Type Package - Nominal current 7A) - Fine


TDA2030A & TDA2030 Amplifier Observations - Voltages 


To get good performance out of this amplifier you will need to run it higher than the minimum voltage of 6V, in fact even at 9V the output is distorted and low power. The sound is clean when at low volume (60db), but push past that level and the sound is terrible.

I have read else where that this chip sings better at 22 volts, but I can't try that. I can report that at 15V (SLA fresh off charge) it performs well. Running with no distortion at full volume (70- 75db).


TDA2030A & TDA2030 Amplifier Observations - Heatsink


The board I purchased came with a very small heatsink. It looked small to me, so I salvaged a heat sink from an ancient graphics card and used that. I also applied some thermal paste between the chip and the sink. 

A Larger Heatsink - Perhaps Not Required
The TDA2030A (or TDA2030) as I configured it does not generate very much heat, the heat sink as pictured above get slightly warm to the touch, so a small heatsink, such as the top picture in the post would probably be OK. 


TDA2030A & TDA2030 Amplifier Observations - How Loud

I would estimate 75db, specs say 85db. So specs say around 10 time more than I do! But this is running at 22V instead of 16V.

In comparison to PAM8403 the TDA2030A is louder, but PAM8610 running at 12V and 1A is far far louder. 

TDA2030A & TDA2030 Amplifier Observations - Sound Quality


The sound quality of this small "Class AB" amplifier is pretty good. It has better than the "Class D" Amplifiers that I have tried. 

I would describe the sound from this amplifier as richer, than the other class D offerings. There seems to be more depth to the sound, it is less flat than the Class D amps. 

I am sorry for the subjective nature of this appraisal, but that is the best I can do. 

TDA2030A & TDA2030 Amplifier Observations -  Pros & Cons


Con - If you were build and battery powered portable speaker with this it would like cost 3 x times that of a Class D build because of the battery. 

Pro - Slightly Better Sound Sound / Richness

TDA2030A & TDA2030 Amplifier Observations - Photos

Very Small Package

Large Battery in Webbing Pouch

Bag of Spanners! (Ugly)

Environmental Permit Applications

Friday, 8 September 2017

Use Apple Pay Without Passcode

Use Apple Pay Without Passcode - Intro


You can NOT do this!

Despite being able to use my "real" contactless card without a passcode, Apple have decided I am a child, and need to be controlled.

There is a slightly less annoying work around. . . . .  or you could just buy a roll of gaffa tape!


Use Apple Pay Without Passcode - Work Around

First off you need to disable touch ID, it is rubbish anyway, being completely unreliable and denies you access to your phone just when you need it, normally when you are in a rush or in a meeting. 

Go To:

Settings > Touch ID and Passcode

If you do not have a passcode then set one up (Turn Passcode On). When you are choosing your new passcode, you will see small writing "passcode options", here you can choose a 4 digit passcode (like the old days), which will keep you safe without wasting your precious time. 


If you are currently using a 6 digit passcode then you will need to:

Settings > Touch ID and Passcode > Turn Passcode Off

and then. . . .

Settings > Touch ID and Passcode > Turn Passcode On

First Turn Passcode On (Turn On and Off to get 4 digit code)

you will then see the above screen with the "Passcode Options". 

Next we need to minimise the number of times you will be required to input the passcode, which can be got down to about 3 or 4 times day using the below option. 

Settings > Touch ID and Passcode > Require Password

By default this is set to "Immediately" which is really annoying. Select "4 hours" or what ever you feel is good for you.


Choose 4 Hour Delay before passcode is required. 

Use Apple Pay Without Passcode -  Conclusion

So you can now use apple pay, only have to use you passcode 3 or 4 times day, and when you pay. It would be very nice if I only had to use passcode when I paid, but like I say I am child and can not be trusted, thank goodness apple are there to protect me!

If like me you are on and off you phone all day perhaps 50 + times (who isn't) this workaround will allow you to use apple pay, whilst only having enter passcode 2 or 3 times a day. 

I hope this keeps you sane, if all else fails just use some gaffa tape to stick your contactless card to the back of you phone. 

Waste Transfer Station Permit

Illustrator Devon