Agilent Technologies 4349B, Руководство пользователя

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4349B
Contact Check K ey
The Contact Check key toggles the contact check function ON and OFF . The Contact Check
function detects a broken cable or miss contact. The decision limit value for a contact is
obtained during the OPEN correction procedure . When an OPEN admittance is measured,
non-connection capacitance is measured and stored. The 4349B compares this value and DUT's
capacitance . The Cont Chk annunciator( 9 ) indicates if the Contact Check function is in the ON
state . The default Contact Check function is OFF .
Open K ey
The Open key executes the OPEN correction function. The OPEN correction data is used to
cancel the oset error of the 4349B and the leakage of the test xture . The OPEN correction
measures also the stray capacitance for the contact check function. The OPEN correction data
is stored in non-volatile memory (EEPROM).
The oset error of 4349B is temperature dependent. F or maximum measurement accuracy ,
P erform the OPEN correction after worming up the 4349B (30 minutes).
P erform the OPEN correction when ambient temperature changes more 6 5 C from the
temperature at which the OPEN correction was performed.
At reset , the correction data is cleared.
Note
OPEN correction must be performed at the condition that test lead or xture
are connected to Ch1, Ch2, Ch3, and Ch4 terminals , without DUT .
K ey Lock K ey
The Key Lock key toggles the disabling and enabling key input from the front panel. When the
key input is disabled, the K ey Lock annunciator( 9 ) will be displayed.
Note
The key lock state can be controlled also through the handler interface . When
the handler key lock function controls the key lock states , all the front-panel
keys are locked out including , so you can only cancel the key lock
out state from handler .
Function Reference 3-9