a couple of highside current sensors...

[server]

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[John S]

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

Am I allowed to use this in my product gratis?

 

[John S]

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

The model is different from the two-transistor configuration. Why?

 

[server]

On Thu, 20 Aug 2020 09:57:35 -0500, John S <Sophi.2@invalid.org>
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0


The model is different from the two-transistor configuration. Why?

Those are just two examples. There are more.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[server]

On Thu, 20 Aug 2020 09:53:12 -0500, John S <Sophi.2@invalid.org>
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0


Am I allowed to use this in my product gratis?

Sure.

This is my most recent current sensor, in one leg of a class-D
h-bridge amp.

https://www.dropbox.com/s/6hifpph45d3hub7/23S902A_sh2.pdf?dl=0

It lets us get the actual current waveform.

I got lucky on the layout; the resistors actually measure 24.9
milliohms. Or maybe it was skill.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[John S]

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

There is a 53mV offset. Why is that?

 

[George Herold]

On Thursday, August 20, 2020 at 10:29:03 AM UTC-4, jla...@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

Huh... (you\'re a wild man, but I\'m missing something.)
For the first one with the opamp. With one amp through R1
there\'s a 1 volt drop.
Which gives 23 volts for U1 output. A 1 volt drop across
R3 or 10 mA of current... that 10 mA must go through the
negative rail resistor R2. ... Which then gives me 10V on your
output.
What did I do wrong?

George H.

--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[George Herold]

On Thursday, August 20, 2020 at 12:09:40 PM UTC-4, George Herold wrote:

On Thursday, August 20, 2020 at 10:29:03 AM UTC-4, jla...@highlandsniptechnology.com wrote:
Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0


Huh... (you\'re a wild man, but I\'m missing something.)
For the first one with the opamp. With one amp through R1
there\'s a 1 volt drop.
Which gives 23 volts for U1 output. A 1 volt drop across
R3 or 10 mA of current... that 10 mA must go through the
negative rail resistor R2. ... Which then gives me 10V on your
output.
What did I do wrong?

George H.

--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[George Herold]

On Thursday, August 20, 2020 at 12:09:40 PM UTC-4, George Herold wrote:

On Thursday, August 20, 2020 at 10:29:03 AM UTC-4, jla...@highlandsniptechnology.com wrote:
Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0


Huh... (you\'re a wild man, but I\'m missing something.)
For the first one with the opamp. With one amp through R1
there\'s a 1 volt drop.

Oops! 0.1V! I found it.... never mind.
GH

Which gives 23 volts for U1 output. A 1 volt drop across
R3 or 10 mA of current... that 10 mA must go through the
negative rail resistor R2. ... Which then gives me 10V on your
output.
What did I do wrong?

George H.

--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[server]

On Thu, 20 Aug 2020 11:07:12 -0500, John S <Sophi.2@invalid.org>
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

There is a 53mV offset. Why is that?

The opamp version? That\'s the supply current of the opamp. Use a lower
current amp, or calibrate it out.

I just used the default universalopamp2

It\'s an idea. It\'s free.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[server]

On Thu, 20 Aug 2020 09:09:35 -0700 (PDT), George Herold
<ggherold@gmail.com> wrote:

On Thursday, August 20, 2020 at 10:29:03 AM UTC-4, jla...@highlandsniptechnology.com wrote:
Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0


Huh... (you\'re a wild man, but I\'m missing something.)
For the first one with the opamp. With one amp through R1
there\'s a 1 volt drop.

100 mV.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[John S]

On 8/20/2020 11:17 AM, jlarkin@highlandsniptechnology.com wrote:

On Thu, 20 Aug 2020 11:07:12 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

There is a 53mV offset. Why is that?

The opamp version? That\'s the supply current of the opamp. Use a lower
current amp, or calibrate it out.

I just used the default universalopamp2

It\'s an idea. It\'s free.

I like it. Thank you!

 

[server]

On Thu, 20 Aug 2020 11:35:57 -0500, John S <Sophi.2@invalid.org>
wrote:

On 8/20/2020 11:17 AM, jlarkin@highlandsniptechnology.com wrote:
On Thu, 20 Aug 2020 11:07:12 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

There is a 53mV offset. Why is that?

The opamp version? That\'s the supply current of the opamp. Use a lower
current amp, or calibrate it out.

I just used the default universalopamp2

It\'s an idea. It\'s free.

I like it. Thank you!

I designed a functional but clumsy highside current sensor into an EOM
driver recently, to protect a $200 distributed amplifier chip. I
should have done this!



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[John S]

On 8/20/2020 12:06 PM, jlarkin@highlandsniptechnology.com wrote:

On Thu, 20 Aug 2020 11:35:57 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 11:17 AM, jlarkin@highlandsniptechnology.com wrote:
On Thu, 20 Aug 2020 11:07:12 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

There is a 53mV offset. Why is that?

The opamp version? That\'s the supply current of the opamp. Use a lower
current amp, or calibrate it out.

I just used the default universalopamp2

It\'s an idea. It\'s free.

I like it. Thank you!


I designed a functional but clumsy highside current sensor into an EOM
driver recently, to protect a $200 distributed amplifier chip. I
should have done this!

My goal is for a current sensor between a solar panel and a battery. It
looks and simulates as I wish.

 

[bitrex]

On 8/20/2020 1:06 PM, jlarkin@highlandsniptechnology.com wrote:

On Thu, 20 Aug 2020 11:35:57 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 11:17 AM, jlarkin@highlandsniptechnology.com wrote:
On Thu, 20 Aug 2020 11:07:12 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

There is a 53mV offset. Why is that?

The opamp version? That\'s the supply current of the opamp. Use a lower
current amp, or calibrate it out.

I just used the default universalopamp2

It\'s an idea. It\'s free.

I like it. Thank you!


I designed a functional but clumsy highside current sensor into an EOM
driver recently, to protect a $200 distributed amplifier chip. I
should have done this!

Zetex IIRC used to make a high-side current-sense IC; basically a Wilson
CM on a chip. It worked good and was cheaper than a quad transistor array.

EOL-ed, naturally

 

[bitrex]

On 8/20/2020 1:12 PM, John S wrote:

On 8/20/2020 12:06 PM, jlarkin@highlandsniptechnology.com wrote:
On Thu, 20 Aug 2020 11:35:57 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 11:17 AM, jlarkin@highlandsniptechnology.com wrote:
On Thu, 20 Aug 2020 11:07:12 -0500, John S <Sophi.2@invalid.org
wrote:

On 8/20/2020 9:28 AM, jlarkin@highlandsniptechnology.com wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0


There is a 53mV offset. Why is that?

The opamp version? That\'s the supply current of the opamp. Use a lower
current amp, or calibrate it out.

I just used the default universalopamp2

It\'s an idea. It\'s free.

I like it. Thank you!


I designed a functional but clumsy highside current sensor into an EOM
driver recently, to protect a $200 distributed amplifier chip. I
should have done this!

My goal is for a current sensor between a solar panel and a battery. It
looks and simulates as I wish.

The differential ADC on an AVR can work about a volt over the
processor\'s supply rail which comes in handy for low-voltage
applications sometimes

 

[legg]

On Thu, 20 Aug 2020 07:28:52 -0700, jlarkin@highlandsniptechnology.com
wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

Which non-ideal op amp models are suitable, do you think?

RL

 

[Tim Williams]

If you\'re going to brag, at least do it in a hand stand with a friend:
https://www.seventransistorlabs.com/Images/BidirectionalCurrentLimiter.png

Tim

--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Design
Website: https://www.seventransistorlabs.com/

<jlarkin@highlandsniptechnology.com> wrote in message
news:g12tjfdie21hpro2h9k2ogmr7era06tpq9@4ax.com...

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[John Larkin]

On Thu, 20 Aug 2020 14:06:32 -0500, \"Tim Williams\"
<tiwill@seventransistorlabs.com> wrote:

If you\'re going to brag, at least do it in a hand stand with a friend:
https://www.seventransistorlabs.com/Images/BidirectionalCurrentLimiter.png

Tim

Interesting use of those 2N3904s.

 

[boB]

On Thu, 20 Aug 2020 07:28:52 -0700, jlarkin@highlandsniptechnology.com
wrote:

Just woke up and these were there.

https://www.dropbox.com/sh/3snkyafrejh23xf/AACNN0tBc1oMV0kJX-rVNMICa?dl=0

We use two channels of high side current sense.... One for battery
side and one for PV input which works up to about 300V and down to
around 10V Bidirectional and up to a bit more than 100A max.

Basically an op amp with some bias and feeding a current source to
feed the low side A/D converter. Like some previous HS current
source tech. We just needed higher voltage so had to build our own.

Current sensing can be quite a painful thing to do well.