Been there, done that: HIP4080 is a piece of ****, when you look at it [monty python].
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So are these mosfet pads voltage readings fine ? I will order new hip4080 and post pics of gate drive and mosfet pad voltages with the hip4080 in it.
Yes 4080 amps are pretty easy to repair, but this one is a chinese pain the a**.
Yes 4080 amps are pretty easy to repair, but this one is a chinese pain the a**.
Post #60 and the attached picture are with the HIP4080 OUT of the socket.
Which terminals 1-2 being bridged are You referring, Perry ?!
Which terminals 1-2 being bridged are You referring, Perry ?!
I've started working back once again on this amplifier.
HIP4080 in place.
I've bridged the drain and source of the low-side FETs.
Noticed something. Gate drive is at what it is supposed to be - sharp square waves at 8vrms.
When there is no signal applied to the RCA there is constant 12.57v DC at A high side, as it should be, but at B side it's sitting on the Low side, not at the high one.
In your guide Perry there is a note - Note About High-Side Drive Power Supplies: it is said that only the high sides needs this 12v above positive rail voltage.
Here are the pin voltages without any signal in the rca.
1-12.75
2-12.15
3-0
4-0
5-12.15
6-6.10
7-1.40
8-5.25
9-5.25
10-12.57
11-12.35
12-0
13-0
14-0
15-12.15
16-12.15
17-0
18-12.15
19-0
20-0
Shouldn't pin 11 and 20 - which are A+B High-side Outputs have both 12.15v and not pin 18 which is B Low-side Output ?
HIP4080 in place.
I've bridged the drain and source of the low-side FETs.
Noticed something. Gate drive is at what it is supposed to be - sharp square waves at 8vrms.
When there is no signal applied to the RCA there is constant 12.57v DC at A high side, as it should be, but at B side it's sitting on the Low side, not at the high one.
In your guide Perry there is a note - Note About High-Side Drive Power Supplies: it is said that only the high sides needs this 12v above positive rail voltage.
Here are the pin voltages without any signal in the rca.
1-12.75
2-12.15
3-0
4-0
5-12.15
6-6.10
7-1.40
8-5.25
9-5.25
10-12.57
11-12.35
12-0
13-0
14-0
15-12.15
16-12.15
17-0
18-12.15
19-0
20-0
Shouldn't pin 11 and 20 - which are A+B High-side Outputs have both 12.15v and not pin 18 which is B Low-side Output ?
The 4080 builds the high-side supply internally via the charge pump that you can see on the diagram in that section.
You shouldn't have straight DC on any gate pad. All drives should be sitting on ground with the low-side G-S shorted.
Do you have the equivalent of IC4C shorted?
You shouldn't have straight DC on any gate pad. All drives should be sitting on ground with the low-side G-S shorted.
Do you have the equivalent of IC4C shorted?
"All drives should be sitting on ground with the low-side G-S shorted." - the picture above shows DRAIN - SOURCE shorted, not Gate-Source. I'm confused...even in the guide it says "Below, pads 2 and 3 for Q12C are bridged with solder " so that's drain and source.
Do you have the equivalent of IC4C shorted? - no, do I need to ?
Pre-amp section is working fine, why do i have to drive the 4080 directly ?
Do you have the equivalent of IC4C shorted? - no, do I need to ?
Pre-amp section is working fine, why do i have to drive the 4080 directly ?
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Sorry. That should be d-s as shown in the photos.
Shorting the op-amp pins will close the feedback loop locally. Without the short, the op-amp output could be virtually anything. With the short, it should bring the voltage to the same as the non-inverting input which should be the same as pin 6 of the 4080.
At this point, you don't need to drive the 4080 directly. The triangle waveform on pin 6 of the 4080 and the straight DC on pin 7 should provide all of the drive you need.
Shorting the op-amp pins will close the feedback loop locally. Without the short, the op-amp output could be virtually anything. With the short, it should bring the voltage to the same as the non-inverting input which should be the same as pin 6 of the 4080.
At this point, you don't need to drive the 4080 directly. The triangle waveform on pin 6 of the 4080 and the straight DC on pin 7 should provide all of the drive you need.
Do you have the equivalent of IC4C shorted? - I've just did.
It is self-oscillating at 65khz with duty cycle of 40% for the low side and 60% for the high side. Don't know if that's okay.
But when i remove the short from IC4C and play 50hz sinewave to the rca - all gates have 50% duty cycle, low and high.
So i suppoose it's alright ?
Time to buy some IRF3710Z...
It is self-oscillating at 65khz with duty cycle of 40% for the low side and 60% for the high side. Don't know if that's okay.
But when i remove the short from IC4C and play 50hz sinewave to the rca - all gates have 50% duty cycle, low and high.
So i suppoose it's alright ?
Time to buy some IRF3710Z...
Did the DC voltage on the 4080 pin 7 match pin 6 when you bridged the op-amp pins?
The duty cycle isn't absolutely critical. What's important is that you have good drive signals.
The duty cycle isn't absolutely critical. What's important is that you have good drive signals.
EARTHQUAKE PH D2
my amp is power up, i'm getting harmonic sound, when i put an input jack in and a bad humming out the output. need your help please. thanks i try to up load schematic.
my amp is power up, i'm getting harmonic sound, when i put an input jack in and a bad humming out the output. need your help please. thanks i try to up load schematic.
Please don't post in a repair thread that was started by someone else unless you are trying to help them.
Start a new thread if you need help with a repair of your own.
http://www.bcae1.com/temp/newthreaddiy01.png
Start a new thread if you need help with a repair of your own.
http://www.bcae1.com/temp/newthreaddiy01.png
Pin 6 has wave at 65khz at 6.08vrms
Pin 7 is straight DC at 6.48vrms.
IC4C has the 6.48vrms at all pins except Vcc- (ground) and Vcc+(+12v).
Is there a DC offset pot?
Are you getting VRMS because you're getting the voltage from your scope?
Are you getting VRMS because you're getting the voltage from your scope?
Yes i'm using the scope, but its a portable one and the gnd is on separate cable-clip.
No, there is no DC offset pot.
No, there is no DC offset pot.
Whatever IC$C is using for its 6v reference appears to be off. What is driving the non-inverting op-amp input of the op-amp that's driving pin 7?
Another bummer...
I have fitted another HIP4080 (new one but it's not really from a reputable source) and one IRF3710Z per bank.
It was working as intended, there was audio and sinewave was clean.
Then i fitted all 12 mosfets (3 per bank) and....the second I've turned the amp on and relay has clicked - the hip4080 got hot and died, taking some mosfets out with it. There wasn't even a high current draw, something like 4-5 amps for couple of seconds.
The IRF3710Z are genuine 100%, as they come from reputable source and I've used them in many other hip based amps with no problems.
The HIP4080 i have my doubts.
So i think i had enough of this amp, i'm going to give up on this one, I don't like burning more money in this.
I have fitted another HIP4080 (new one but it's not really from a reputable source) and one IRF3710Z per bank.
It was working as intended, there was audio and sinewave was clean.
Then i fitted all 12 mosfets (3 per bank) and....the second I've turned the amp on and relay has clicked - the hip4080 got hot and died, taking some mosfets out with it. There wasn't even a high current draw, something like 4-5 amps for couple of seconds.
The IRF3710Z are genuine 100%, as they come from reputable source and I've used them in many other hip based amps with no problems.
The HIP4080 i have my doubts.
So i think i had enough of this amp, i'm going to give up on this one, I don't like burning more money in this.