Smiths Medical BCI 3304, Service Manual

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Chapter 2: Oximeter Circuit Description
3304 Service Manual 2-11
voltage Test Points
Unless otherwise noted, all voltages are measured with respect to
ground at TP-1.
LOCATIOn COnDITIOn nOMInAL AnD RAnge
TP2 Oximeter on. 5 VDC, ± 0.25 VDC
ANA+5 Same as TP2. Same as TP2.
FLTR+5 Same as TP2. Same as TP2.
TP3 Oximeter on. -4.8 VDC to -6.2 VDC
ANA-5 Same as TP3. Same as TP3.
FLTR-5 Same as TP3. Same as TP3.
V-REF Oximeter on. 2.500 VDC
V-RAM Oximeter on or off. 5VDC, ± 0.25 VDC.
U10-71 Oximeter on. 6.144 MHz, 50% duty cycle.
TP7 Referred to TP6. 4.7 VDC to 5.3 VDC
TP5 Oximeter on or off. 5.2 VDC to 7.2 VDC depending on the
state of the charge of the battery.
TP14 Oximeter is on. 3.65 VDC ± 0.1 VDC.
Waveform Test Points
The waveforms are measured with respect to ground at TP1. •
The oscilloscope is triggered on TP16, falling edge. •
The waveforms are measured with the finger probe attached to •
the oximeter with finger or piece of paper in probe.