What voltage caps ?

I thought that M might be the tolerance code (M = +/-20%) and 7 possibly the material code. This leaves the '50' as the voltage rating of 50V.

** The cap exhibits a negative tempco of about 750ppm.

M might just stand for "minus".

The colour is the only clue left for voltage.

..... Phil

it must be 470pF and +/-20% 750V. I find it hard to believe it has

750ppm per degree, what is it from?

"MisterE"

** Better go look up " temperature compensating ceramic capacitors " on Google.

Bit old hat for the uP, MP3 and IT generation - I know.

** Did you see the pic?

..... Phil

That was my thinking too. Expected now to be slandered mercilessly.

Graham

On Thu, 14 Aug 2008 19:01:14 +0100, Eeyore put finger to keyboard and composed:

There are NPO, N150, N750, N1500 ceramic caps, for example.

N750 caps have a tempco of -750ppm/degC.

That doesn't quite gel with "M750", though.

See

- Franc Zabkar

--
Please remove one \'i\' from my address when replying by email.

:On Thu, 14 Aug 2008 19:01:14 +0100, Eeyore : put finger to keyboard and :composed: : :>MisterE wrote: :>

:>> it must be 470pF and +/-20% 750V. :>

:>That was my thinking too. Expected now to be slandered mercilessly. :>

:>Graham : :There are NPO, N150, N750, N1500 ceramic caps, for example. : :N750 caps have a tempco of -750ppm/degC. : :That doesn't quite gel with "M750", though. : :See :

: :- Franc Zabkar

You are correct Franc. My guess is that the manufacturer chose to substitute the N with the M since the 750 by itself infers the tempco, and since this characteristic is invariably negative there is no need to put the N. The substitute M is a neat way of providing the capacitance tolerance (+/-20%) while saving extra characters in the limited space available.

:

the

while

Sounds moderately convincing. Doesn't solve the voltage rating problem though.

Graham

: : :Ross Herbert wrote: : :> Franc Zabkar wrote: :> :Eeyore: put finger to keyboard and:composed: :> :>MisterE wrote: :> :>

:> :>> it must be 470pF and +/-20% 750V. :> :>

:> :>That was my thinking too. Expected now to be slandered mercilessly. :> :>

:> :>Graham :> : :> :There are NPO, N150, N750, N1500 ceramic caps, for example. :> : :> :N750 caps have a tempco of -750ppm/degC. :> : :> :That doesn't quite gel with "M750", though. :> : :> :See :>

:

:> : :> : :> :- Franc Zabkar :>

:> You are correct Franc. My guess is that the manufacturer chose to substitute the :> N with the M since the 750 by itself infers the tempco, and since this :> characteristic is invariably negative there is no need to put the N. The :> substitute M is a neat way of providing the capacitance tolerance (+/-20%) while :> saving extra characters in the limited space available. : :Sounds moderately convincing. Doesn't solve the voltage rating problem though. : :Graham :

Graham, If you have been following this thread then you will note that I gave my opinion on the voltage previously. I was simply replying to Franc on the topic of the use of M in place of N ahead of the 750. You didn't respond to Franc's post by saying that his post didn't solve the voltage problem so why do so with mine. If you can't offer some constructive comment then say nothing.

"Ross Herbert"

** Such complaints are just water off a duck's back to psychopathic narcissists like Graham Stevenson.

Even his web page is totally vacuous:

All bloat, no substance.

....... Phil

On Thu, 14 Aug 2008 19:28:19 +1000, MisterE put finger to keyboard and composed:

750ppm over a range of 100degC would equate to ... 750 * 100 * 100 / 1000000 = 7.5%

- Franc Zabkar

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