Datasheet

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10.0 Test Conditions
This section contains information relating to the specific
test environments, including stimulus and loading parame-
ters, for the DP83843. These test conditions are catego-
rized in the following subsections by each type of
pin/interface including:
— FXTD/AUITD+/− Outputs sourcing AUI
— FXTD/AUITD+/− Outputs sourcing 100BASE-FX
— CMOS Outputs i.e. MII and LEDs
— TPTD+/− Outputs sourcing 100BASE-TX
— TPTD+/− Outputs sourcing 10BASE-T
Additionally, testing conditions for Idd measurements are
included.
10.1 FXTD/AUITD+/− Outputs (sourcing AUI lev-
els)
When configured for AUI operation, these differential out-
puts source Manchester encoded 10 Mb/s data at AUI logic
levels. These outputs are loaded as illustrated in Figure 26.
10.2 FXTD/AUITD+/− Outputs (sourcing PECL)
When configured for 100BASE-FX operation, these differ-
ential outputs source unscrambled 125 Mb/s data at PECL
logic levels. These outputs are loaded as illustrated in
Figure 27.
10.3 CMOS Outputs (MII and LED)
Each of the MII and LED outputs are loaded with a con-
trolled current source to either ground or V
CC
for testing
Voh, Vol, and AC parametrics. The associated capacitance
of this load is 50 pF. The diagram in Figure 28 illustrates
the test configuration.
It should be noted that the current source and sink limits
are set to 4.0 mA when testing/loading the MII output pins.
The current source and sink limits are set to 2.5 mA when
testing/loading the LED output pins.
10.4 TPTD+/− Outputs (sourcing 10BASE-T)
When configured for 10BASE-T operation, these differen-
tial outputs source Manchester encoded binary data at
10BASE-T logic levels. These outputs are loaded as illus-
trated in Figure 29. Note that the transmit amplitude mea-
surements are made across the secondary of the transmit
transformer as specified by the IEEE 802.3 specification.
10.5 TPTD+/− Outputs (sourcing 100BASE-TX)
When configured for 100BASE-TX operation, these differ-
ential outputs source scrambled 125Mb/s data at MLT-3
logic levels. These outputs are loaded as illustrated in
Figure 29. Note that the transmit amplitude and rise/fall
time measurements are made across the secondary of the
transmit transformer as specified by the IEEE 802.3u spec-
ification.
10.6 Idd Measurement Conditions
The DP83843 PHYTER is currently tested for total device
Idd under four operational modes:
— 100BASE-TX Full Duplex (max packet length / min IPG)
— 10BASE-TX Half Duplex (max packet length / min IPG)
— 100BASE-FX Full Duplex (max packet length / min IPG)
Figure 26. AUI Test Load
AUITD AUIRD AUICD
39Ω
39Ω
39Ω
39Ω
.01µF
.01
µF
78
Ω
27µH
200
Ω
200Ω
TYPICAL AUI
TRANSMIT LOAD
100µH TRANSFORMER
DB-15 CONNECTOR