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Old 26th August 2010, 11:55 AM   #461
AP2 is offline AP2  Italy
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Quote:
Originally Posted by savu View Post
you are right, but if you use all smd package like sop, or even bga or lga, with board make out of copper coated in silver (for better rfi performance) and use shields like in mobile phones you can get some pretty results.

regards,
savu
yes, it is possible ,I have no doubt, I have had this experience.
The road is long, trim THD and IMD faults or frequency response or vice versa etc..
thinks about parameters, stability, linearity to load and modulation, linearity of thd, high frequency response, good protection. only when you want to make head against the wall might have finished the job. eheh!

Last edited by AP2; 26th August 2010 at 12:01 PM.
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Old 26th August 2010, 12:54 PM   #462
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Whatever else i try in the simulation, i get 200+ nS propagation delay in the level shifter.
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Old 26th August 2010, 01:28 PM   #463
Andy F is offline Andy F  Spain
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Hi:

Increment supply voltage on the simulation.
For level shift you can use this one:
Attached Files
File Type: pdf levelshift.pdf (5.0 KB, 689 views)
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Old 26th August 2010, 01:39 PM   #464
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Thats what i've tried but ltspice claims like atleast 150-200nS propagation delay.
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Old 26th August 2010, 01:40 PM   #465
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TL3016 comparators are readily available. Pin-compatible with the LT1016 and lower supply current.
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Old 26th August 2010, 02:34 PM   #466
Eva is offline Eva  Spain
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Quote:
Originally Posted by Andy F View Post
Hi:

Increment supply voltage on the simulation.
For level shift you can use this one:
Low value capacitors like 10pf in parallel with the 680 ohm resistors can result in even lower propagation delay.
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Old 26th August 2010, 02:46 PM   #467
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I found some 10pF capacitors in the IR2110 model which i doubt should be there, with a parallel resistance set to 750k, when i removed these, i get a more reasonable 40-80nS propagation delay over the level shifter.

I wonder whwere the creator of the IR2110 model found that input capacitance, theres no mention of it in the datasheet, did he do an actual capacitance measurement of the input ?
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Old 26th August 2010, 02:58 PM   #468
Eva is offline Eva  Spain
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Those 10pf were not that wrong, the IC may have 2-5pf input capacitance like logic gates, and the rest comes from PCB layout and collector-base capacitance of the level shifter...

Resistors may exhibit 1pf shunt capacitance too...

In simulation you can just delete parasitics, but what are you going to do in real life?

(Drive them from a lower impedance.)
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Old 26th August 2010, 04:09 PM   #469
savu is offline savu  Romania
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[QUOTE=Andy F;2284239]Hi:

Increment supply voltage on the simulation.QUOTE]

hello andy,

any hint on how to do the increment stuff ?

regards,
savu
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Old 26th August 2010, 05:13 PM   #470
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Default Class D clipping anyone ?

Heres a video of me clipping testing my prototype:
YouTube - Prototype class d amplifier clipping test
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