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S G N A L P A T H / H N O T S E L E C T E D

3490 INTEGRATOR

I N P U T T E R M I N A L

-R E F E R A N C E < + R E F E R A N C E J

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O T H E R 3 4 9 O A

C O N T R O L A N O

T I M I N G C I R C U I T S

EXAMPLE OF TRACK/HOLD MEA-SUREMENTSEOUENCE

a' During the period 6T1, circuits are in the Tract+,Mode and in'putswitch SA is connected to the lnput terminal.

P'.f'1r a S/H T-riggercommand is received. Circuit A holds within 400 nanoseconds,and Circuit B holds about 2 milliseconds later.

c. At t2, 54 is switched to ground. 2T3 is settling time for the amplifiers.

d' 3To is the run-up time for the integrator. sg is connected to the I ntegrator inpu.

e' From t4to t7,sg is crosetJto ground and no current is suppried to the Integrator.

f' At t5, s4 is switched to the - Reference. 5T6 is about 4 ms long. Hold A occurs 2 ms after t5 and Hold B occurs at t6.

9. 54 is switched to ground at t6, and 6T7 is used for amplifier settling time.

h' sg is switched to the lntegrator input during 7Tg. tg is the zero detect point.

i' At t0, all circuits are returned to the Track Mode and s4 is again connected to the lnput terminal.

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Decay of circuit A output signal, v3, is eägger;d for the purpose of this iilustration.