Datasheet

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    
SLLS418I − JUNE 2000 − REVISED DECEMBER 2004
7
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
POST OFFICE BOX 1443
HOUSTON, TEXAS 77251−1443
Terminal Functions
TERMINAL
I/O
DESCRIPTION
NAME TYPE NO.
I/O
DESCRIPTION
AGND Supply 36, 37, 38,
39, 40, 41,
60, 61, 64,
65
Analog circuit ground terminals. These terminals must be tied together to the low-impedance circuit
board ground plane.
AV
DD
Supply 34, 35, 47,
48, 54, 62,
63
Analog circuit power terminals. A combination of high-frequency decoupling capacitors near each
terminal are suggested, such as paralleled 0.1 µF and 0.001 µF. Lower frequency 10-µF filtering
capacitors are also recommended. These supply terminals are separated from PLLV
DD
and DV
DD
internal to the device to provide noise isolation. They must be tied at a low-impedance point on the
circuit board.
CNA CMOS 17 O Cable not active output. This terminal is asserted high when there are no ports receiving incoming bias
voltage.
CPS CMOS 27 I Cable power status input. This terminal is normally connected to cable power through a 400-k
resistor. This circuit drives an internal comparator that is used to detect the presence of cable power.
This terminal must be tied to DGND through a 1-k resistor if application does not require it to be used.
CTL0
CTL1
CMOS
5 V tol
4
5
I/O Control I/Os. These bidirectional signals control communication between the TSB41AB3 and the LLC.
Bus holders are built into these terminals.
C/LKON CMOS 22 I/O Bus manager contender programming input and link-on output. On hardware reset, this terminal is
used to set the default value of the contender status indicated during self-ID. Programming is done by
tying the terminal through a 10-k resistor to a high (contender) or low (not contender). The resistor
allows the link-on output to override the input. However, it is recommended that this terminal be
programmed low, and that the contender status be set via the C register bit.
If the TSB41AB3 is used with an LLC that has a dedicated terminal for monitoring LKON and also
setting the contender status, then a 10-k series resistor is placed on the LKON line between the PHY
and LLC to prevent bus contention.
Following hardware reset, this terminal is the link-on output, which is used to notify the LLC to
power-up and become active. The link-on output is a square-wave signal with a period of
approximately 163 ns (8 SYSCLK cycles) when active. The link-on output is otherwise driven low,
except during hardware reset when it is high impedance.
The link-on output is activated if the LLC is inactive (LPS inactive or the LCtrl bit cleared) and when one
of the following is true:
a) the PHY receives a link-on PHY packet addressed to this node
b) the PEI (port-event interrupt) register bit is 1
c) any of the CTOI (configuration-timeout interrupt), CPSI (cable-power-status interrupt), or STOI
(state-timeout interrupt) register bits are 1 and the RPIE (resuming-port interrupt enable) register
bit is also 1.
Once activated, the link-on output stays active until the LLC becomes active (both LPS active and the
LCtrl bit set). The PHY also deasserts the link-on output when a bus-reset occurs unless the link-on
output is otherwise active because one of the interrupt bits is set (i.e., the link-on output is active due
solely to the reception of a link-on PHY packet).
NOTE: If an interrupt condition exists which otherwise causes the link-on output to be activated if the
LLC were inactive, the link-on output is activated when the LLC subsequently becomes inactive.
DGND Supply 3, 16, 20,
21, 28, 70,
80
Digital circuit ground terminals. These terminals must be tied together to a low-impedance point on the
circuit board ground plane.
D0−D7 CMOS
5 V tol
7, 8, 10,
11, 12, 13,
14, 15
I/O Data I/Os. These are bidirectional data signals between the TSB41AB3 and the LLC. Bus holders are
built into these terminals.
DV
DD
Supply 6, 29, 30,
68, 69, 79
Digital circuit power terminals. A combination of high-frequency decoupling capacitors near each
terminal is suggested, such as paralleled 0.1 µF and 0.001 µF. Lower frequency 10-µF filtering
capacitors are also recommended. These supply terminals are separated from PLLV
DD
and AV
DD
internal to the device to provide noise isolation. They must be tied at a low-impedance point on the
circuit board.