
Page 49
Cortina Systems LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers
LXT9785/LXT9785E
Datasheet
249241, Revision 11.0
16 April 2007
3.2 PQFP Signal Descriptions
109, 123,
138, 152
N6, N7,
N9, N11,
N12
VCCT
-
Analog Power Supply - Transmit.
+2.5 V supply for all analog transmit circuits.
66, 79,
183, 195
A1, A9,
B3, B7,
C5, C13,
C17, D1,
D3, D6,
D10, D15,
E5, E7,
E9, E11,
E13, E17,
F13, H8,
H9, H10,
J8, J9,
J10, K8,
K9, K10
GNDD
-
Digital Ground.
Ground return for core digital supplies (VCCD). All
ground pins can be tied together using a single ground
plane.
9, 19, 30,
38, 48, 57,
74, 188,
199, 207
–
GNDIO
-
Digital GND - I/O Ring.
Ground return for digital I/O circuits (VCCIO).
99, 163
M5, M13
GNDPECL
-
Digital GND - PECL Signal Detect Inputs.
Ground return for PECL Signal Detect input circuits.
106, 112,
120, 126,
135, 141,
149, 155
P5, P6,
P13, R7,
R9, R11,
R13, U8
GNDR
-
Analog Ground - Receive.
Ground return for receive analog supply. All ground
pins can be tied together using a single ground plane.
113, 127,
134, 148
P14, R1,
R3, R5,
R15, R17,
T17, U2,
U4, U6,
U10, U12,
U14, U16,
U17
GNDT
-
Analog Ground - Transmit.
Ground return for transmit analog supply. All ground
pins can be tied together using a single ground plane.
179
K14
SGND
-
Substrate Ground.
Ground for chip substrate. All ground pins can be tied
together using a single ground plane.
Table 15
Power Supply Signal Descriptions – PQFP (Sheet 2 of 2)
Pin/Ball Designation
Symbol
Type
Signal Description
PQFP
PBGA
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.