Is there a Spice model of a photo diode that delivers

current ( laser_power, Vbias ...) ??

I'm not yet bound to a certain type.
Application is low frequency, but very low noise.

And Phil, some of your papers were a tremendous help!

Cheers, Gerhard

On a sunny day (Wed, 14 Dec 2022 12:29:07 +0100) it happened Gerhard Hoffmann
<dk4xp@arcor.de> wrote in <tncc23$11oj7$1@solani.org>:

>
>Is there a Spice model of a photo diode that delivers
>
>current ( laser_power, Vbias ...) ??
>
>I'm not yet bound to a certain type.
>Application is low frequency, but very low noise.
>
>
>And Phil, some of your papers were a tremendous help!
>
>Cheers, Gerhard

Yes burning papers can be a big help now it is freezing and prices have gone up
because of the war in Europe triggered by the half senile US ByeThen preCendent
and his corrupt criminal drugs addicted son.

On Wed, 14 Dec 2022 12:29:07 +0100, Gerhard Hoffmann <dk4xp@arcor.de>
wrote:

>
>Is there a Spice model of a photo diode that delivers
>
>current ( laser_power, Vbias ...) ??
>
>I'm not yet bound to a certain type.
>Application is low frequency, but very low noise.
>
>
>And Phil, some of your papers were a tremendous help!
>
>Cheers, Gerhard

A cap in parallel with a current source is usually good enough. Or a
current source in parallel with a diode if you expect a lot of voltage
swing; that's about what a photodiode is.

Gerhard Hoffmann wrote:
>
> Is there a Spice model of a photo diode that delivers
>
> current ( laser_power, Vbias ...) ??
>
> I'm not yet bound to a certain type.
> Application is low frequency, but very low noise.
>
>
> And Phil, some of your papers were a tremendous help!
>
> Cheers, Gerhard
>

Glad you like them. Besides the current source and capacitor that John
mentions, you also have to care about the series resistance. Devices
that look identical, such as the dice in the BPW34 and SFH206K, can have
very different resistances (50 vs 300 ohms in that case).

That resistance adds its Johnson noise to the op amp's voltage noise,
which seriously limits how well you can do with bootstrapping.

Hamamatsu has some nice devices, e.g. the S6968, which is a giant lensed
thing with about 40 pF of capacitance and only a couple of ohms Rseries.

Cheers

Phil Hobbs

(Currently working on a training seminar for Hamamatsu apps engineers)

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

Gerhard Hoffmann wrote:
>
> Is there a Spice model of a photo diode that delivers
>
> current ( laser_power, Vbias ...) ??
>
> I'm not yet bound to a certain type.
> Application is low frequency, but very low noise.

The conventional photodiode SPICE model's shown below.

Important standard diode model SPICE parameters:

EG Bandgap
IS Saturation current
Rs Series resistance of Dfwd diode
CJO Zero-bias p-n capacitance
M Grading coefficient of p-n junction
IS Saturation current
N Emission coefficient
Rsh Shunt resistance
Iph Photocurrent

Pertinent schematic:

<https://crcomp.net/spice/photodiode.png>

Iph is a constant current source, the photocurrent.
Rsh Shunt resistance. Derived from +10mV and -10mV with measured
current. Determines noise current in photovoltaic mode.
Rs Contact and non depleted semiconductor resistance. Determines rise
time and the linearity.
Cj Junction capacitance. Determines the response speed.

Danke,

--
Don, KB7RPU, https://www.qsl.net/kb7rpu
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.