Photo Measurements

DESIGN PHASE:       measurement
SUB ELEMENT NAME:   photo measurements
VARIABLE NAME:      [HEMPHOTO]
DATE:               REVISION LETTER:    REVISION DATE:  
APPLICABILITY:      regulators or feedback circuits

ACTIVITY:  Measure transients, ripple, and noise measurements
usually recorded as photographs or plots from a digital
oscilloscope.

OUTPUT:  Photographs or plots from a digital oscilloscope in
laboratory notebook for comparison to specifications and
analysis.

ALGORITHM:

[HEMPHOTO] =   total engineer time for photo measurements
[HTMPHOTO] =   total technician time for photo measurements
0.0+           set up time in hours
0.0*           measurement time per photo in hours
[NPHOTO]       number of photo measurements

[NPHOTO] =
[NIT]+         2*[INPUT COUNT]*[OUTPUT COUNT]
               number of input voltage transient measurements
               (step and impulse spike)
[NLT]+         [OUTPUT COUNT]
               number of load transient measurements (step)
[NIR]+         [INPUT COUNT]
               number of inrush current measurements
[NHT]+         [INPUT COUNT]
               number of hold-up-time measurements
[NSR]+         [OUTPUT COUNT]
               number of short circuit recovery measurements
[NOS]+         [OUTPUT COUNT]
               number of turn on overshoot measurements
[NOD]+         [OUTPUT COUNT]
               number of turn off decay measurements
[NPA]+         [OUTPUT COUNT]
               number of periodic and random noise measurements
[NFB]+         1 for regulators
               number of forward biased secondary breakdown
               measurements

[NPHOTO] = 2*[INPUT COUNT]*[OUTPUT COUNT] +2*[INPUT COUNT]
           +5*[OUTPUT COUNT]

DISCUSSION:

Author: Jerrold Foutz, foutz@smpstech.com

Original: Foutz, J., Power Supply Circuit Development Estimating Aid - An Expert System Application, IEEE Applied Power Electronics Conference Record, New Orleans, February 1-5, 1988. Revised 21 February 2001