Tektronix 494AP O o O a o o A o, Ruooeour, Theory of Operaton 494l4g4Ap Servlce,Vot

Theory of Operaton - 494[l4g4Ap Servlce,Vot. 1

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	PREAiIPLIFIER

INTEGRATOR

V MODEOUT

'141&126

Figure7-26. Simpliliedtune voltage converler.

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In additionto ihe six steeringlines that drive the steeringgates,U4025also suppliesthe trackc(coarse) and trackf (fine) lines, which control the track/hold selectortransistorfor each converterside. Tabte7-19 illustratesthe formatfor ADDRESS70. Table7-20tists some of the significantstatesthat are usedto tune the DAC.

The third output from U4045,ADDRESS80, controls transistors01058 and O2017.which enablethe write- backfunction.

Slorage Reglsters. Six storage registersare used in the circuit,U3015,U3025,U3035,U3050,U3060,and U3070. Since both sets are identical,only the coarse tune sectionwill be described.

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7-74

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