Agilent Technologies 93000 SOC Series Training Manual page 403

14-4 Measuring DC Output Voltages
Agilent 93000 SOC Series User Training Part 1, October 2004
Output Low Level (VOL)
You force (for example, using a PMU) a current IOL according to the
device specs on the output pins in logical low state and measure the
associated output voltage VOL. For a good device VOL must not exceed
a certain upper limit specified for the device (see Table 3,
Voltages for VCC = 5.5V,"
Measuring VOL at a given current IOL and setting an upper limit
VOL for the resulting VOL value means that the resistance of a
max
device output pin must not exceed a limit given by
VOL /IOL.
max
In other words, this tests checks the conductivity of the output pin in
logical low state.
Output High Level (VOH)
The basic ideas behind the VOH measurement are the same as for the
VOL measurement described above:
You force (for example, using a PMU) a current IOH according to the
device specs on the output pins in logical high state and measure the
associated output voltage VOH. For a good device VOH must be greater
than a certain lower limit specified for the device (see Table 3,
Output Voltages for VCC = 5.5V,"
Measuring VOH at a given current IOH and setting a lower limit VOL
for the resulting VOH value means that the resistance of a device
output pin must not exceed a limit given by
(VCC - VOL )/IOL.
min
In other words, this tests checks the conductivity of the output pin in
logical high state.
Setting Up the Output DC Testfunction
(IOL = IOH = 50
The output DC test we want to execute with the 74ACT299
shift/storage register on the pins io_pins and ser_out is the following:
• We measure VOL and VOH for an input current of 50
to the specification of Table 3,
on page 402 a good device must meet the following requirements for
VCC = 5.5V:
VOL < 0.1V
VOH > 5.4 V
Device Characterization - DC Tests
on page 402).
on page 402).
A)
µ
"DC Output Voltages for VCC = 5.5V,"
"DC Output
"DC
min
µ
A. According
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