
LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers
42
Datasheet
Document Number: 249241
Revision Number: 010
Revision Date: 30-May-2006
Table 12. JTAG Test Signal Descriptions – PQFP
Pin/Ball
Designation
Symbol
Type1
Signal Description2,3
PQFP
PBGA
167
N14
TDI
I, ST, IP
Test Data Input.
Test data sampled with respect to the rising edge of TCK.
168
N15
TDO
O, TS
Test Data Output.
Test data driven with respect to the falling edge of TCK.
169
N16
TMS
I, ST, IP
Test Mode Select.
170
M16
TCK
I, ST, ID
Test Clock.
Clock input for JTAG test.
171
M17
TRST
I, ST, IP
Test Reset.
Reset input for JTAG test.
1. Type Column Coding: I = Input, O = Output, OD = Open Drain, TS = Three-State-able output, SMT =
Schmitt Triggered input, SL = Slew-rate Limited output, IP = weak Internal Pull-up, ID = weak Internal pull-
Down.
2. The IP/ID resistors are disabled during H/W Power-Down mode. If a pin is an output or an I/O, the IP/ID
resistors are also disabled when the output is enabled.
3. TDO output is three-stated in H/W Power-Down mode and during H/W reset.
Table 13. Miscellaneous Signal Descriptions – PQFP (Sheet 1 of 4)
Pin/Ball
Designation
Symbol
Type1
Signal Description2
PQFP
PBGA
94
93
N3,
M4
TxSLEW_0
TxSLEW_1
I, ST, ID
Tx Output Slew Controls 0 and 1 Defaults.
These pins are read at startup or reset. Their value at
that time is used to set the default state of Register bits
27.11:10 for all ports. These register bits can be read
and overwritten after startup / reset.
These pins select the TX output slew rate for all ports
(rise and fall time) as follows:
TxSLEW_1
TxSLEW_0
Slew Rate (Rise and Fall
Time)
0
3.3 ns
0
1
3.6 ns
1
0
3.9 ns
1
4.2 ns
1. Type Column Coding: I = Input, O = Output, OD = Open Drain Output, ST = Schmitt Triggered Input, TS =
Three-State-able Output, SL = Slew-rate Limited Output, IP = Weak Internal Pull-Up, ID = Weak Internal
Pull-Down.
2. The IP/ID resistors are disabled during hardware power-down mode.
3. The LINKHOLD ability is available only for stepping 4 (Revision D0).