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155-0076-00: Difference between revisions
→Probe Readout Ring Decoder
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11 kΩ to ground represents a 10x probe. | 11 kΩ to ground represents a 10x probe. | ||
6.2 kΩ to ground represents a 100k probe. | 6.2 kΩ to ground represents a 100k probe. | ||
When the ring is left floating, it is pulled up to 5 volts. | |||
In this case, the voltages are as shown in the schematic. | |||
Q62, Q56, and Q51 are on, and Q63, Q57, and Q52 are off. | |||
Current is allowed to flow out of the base of Q68, and | |||
consequently the darlington pair of Q69 and Q70 is turned on, | |||
sinking current from the X1 pin of the M94. | |||
==Used in== | ==Used in== | ||