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Entry  Sat Mar 25 22:43:46 2017, johannes, Noise Hunting, Cavity, CryoCoatingCavs Ringdowns, Error Signals & Co 6x
    Reply  Tue Apr 4 08:18:31 2017, johannes, Noise Hunting, Noise Budget, LB1005 internal noise LB1005_GainSettings_comp.pdfLB1005_East_noise.pdfLB1005_West_noise.pdfbeat_sense_noise.pdf
       Reply  Wed Apr 5 23:27:12 2017, johannes, Noise Hunting, Noise Budget, Sensing noise error_noise_west_20170405b.pdferror_noise_east_20170405b.pdferror_noises_west_20170405b.pdferror_noises_east_20170405b.pdf
          Reply  Fri Apr 7 01:44:22 2017, johannes, Noise Hunting, Noise Budget, Sensing noise 6x
             Reply  Fri Apr 7 02:09:31 2017, Koji, Noise Hunting, Noise Budget, Sensing noise 
          Reply  Sat Apr 8 12:53:33 2017, johannes, Notes, PDH, RIO planex amplitude response laser_response_20170407.pdf
             Reply  Mon Apr 17 16:27:54 2017, johannes, Notes, PDH, RIO planex amplitude response TFAG4395A_17-04-2017_152730.pdfcurrent_driver_mod.pdf
                Reply  Wed Apr 19 12:48:06 2017, johannes, Notes, Laser, Current driver oscillations current_driver_mod.pdfAG4395A_18-04-2017_181713.pdf
                   Reply  Fri Apr 28 11:37:41 2017, johannes, Notes, Laser, RFPD transfer functions RFPD_response_20170413.pdf
                      Reply  Thu May 4 19:13:04 2017, johannes, Notes, Laser, RIO planex frequency response laser_frequency_response.pdfpll_scheme.pdflaser_response_20170504.pdf
                         Reply  Tue May 9 16:18:02 2017, rana, Notes, Laser, LB1005 Transfer Function 
                            Reply  Thu Jun 15 13:58:17 2017, johannes, Notes, Laser, Laser frequency response west_response_20170614.pdf
                      Reply  Wed Jun 14 18:37:15 2017, johannes, Notes, Laser, RFPD circuitry RFPD_notches.jpgRFPD_WEST.jpgRFPD_EAST.jpg
                         Reply  Thu Jun 15 09:24:06 2017, Chris, Notes, Laser, RFPD circuitry 
                            Reply  Thu Jun 15 11:39:03 2017, Koji, Notes, Laser, RFPD circuitry 
                         Reply  Sat Jun 17 02:56:26 2017, johannes, Notes, Laser, RFPD circuitry IMG_20170616_143847305.jpg
                            Reply  Sun Jul 9 21:56:07 2017, johannes, Notes, Laser, RFPD circuitry resPD_20170622.pdf
Message ID: 1596     Entry time: Thu Jun 15 11:39:03 2017     In reply to: 1595
Author: Koji 
Type: Notes 
Category: Laser 
Subject: RFPD circuitry 
  Vn [nV/rtHz] In [pA/rtHz] Slew Rate [V/us]
MAX4107 0.75 2.5 500
LMH6624 0.92 2.3 360
OPA847 1.0 3.7 625

That iLIGO golden PD circuit exhibited the transimpedance of ~2kOhm at 33MHz at the 40m.
Considering the gain of 10 in the preamplifier, the  resonant circuit shows the equivalent resistance of ~200Ohm at the resonant freq of ~30MHz.
This becomes the source impedance for the preamp. 

You can put the parameters in the formula in P18 of LMH6624 data sheet (standard noise calculation), you basically get ~2nV/rtHz input equivalent noise, which corresponds to ~11pA/rtHz current noise reffered to the photocurrent. The noise levels are n(MAX4107)<n(LMH6624)<n(OPA847), but not much change.
The shot noise intercept DC currents for them are 0.38, 0.40, 0.44mA, respectively.

This means that MAX is the best although it is a discontinued chip.
LMH is slow w.r.t. the slew rate and not that low noise compared to MAX.
OPA is fast and slightly more noisy.

MAX is known to have soft saturation, but it might also be true that all of them have this issue.

Note that they tends to be unstable. Particularly, LMH and OPA are not stable at the gain of +10. You need to increase the gain to +15 or even +20 to mae it stable. This equivalently lower the slew rate (--- should we call it "input equivalent slew rate"???). So again MAX seems a little better.

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