78Q2120C Teridian Semiconductor Corp. (TDK Semiconductor), 78Q2120C Datasheet - Page 9

• Manufacturer Part Number: 78Q2120C
• Description: 10/100 Ethernet PHYS
• Manufacturer: Teridian Semiconductor Corp. (TDK Semiconductor)

78Q2120C
10/100BASE-TX Transceiver
LED INDICATORS
The LED pins use standard logic drivers. They output a logic low when the LED is meant to be on and a logic
high when it is meant to be off. The LED should be connected in series with a resistor between the output pin and
the power supply.
OSCILLATOR/CLOCK
MISCELLANEOUS PIN
POWER SUPPLY AND GROUND
© 2003 TDK Semiconductor Corporation, Proprietary and Confidential
LEDL
LEDTX
LEDRX
LEDCOL
LEDBTX
LEDBT
LEDFDX
CKIN
XTLP/N
INTR
NC
NAME
VCC
GND
NAME
NAME
NAME
42,53,55,60
43,57,63
3,5,9,10,
8,11,41,
PIN
59,58
54,56
PIN
PIN
PIN
40
39
38
37
36
48
49
35
4
TYPE
TYPE
TYPE
COZ
CIS
TYPE
CO
CO
CO
CO
CO
CO
CO
A
--
G
S
DESCRIPTION
LED LINK: ON for link up.
LED TRANSMIT: ON when there is a transmission (normally OFF).
LED RECEIVE: ON when there is a reception (normally OFF).
LED COLLISION: In half duplex mode, this is a collision indicator and turns ON
when a collision occurs. In full duplex mode, this LED is held OFF.
LED 100BASE-TX: ON for 100BASE-TX connection and OFF for other
connections. LEDBTX is OFF during auto-negotiation.
LED 10BASE-T: ON for 10BASE-T connection and OFF for other
connections. LEDBT is OFF during auto-negotiation.
LED FULL DUPLEX: ON when in full duplex mode and OFF when in half
duplex mode.
DESCRIPTION
CLOCK INPUT: Connects to a 25 MHz clock source. This pin should be
held low when XTLP and XTLN are being used as the 25 MHz clock source.
CRYSTAL PINS: Should be connected to a 25 MHz crystal. When CKIN is
being used as the 25 MHz clock source, these pins should be left floating or
connected together.
DESCRIPTION
INTERRUPT PIN: This pin is used to signal an interrupt to the media access
controller. The pin is held in the high impedance state when an interrupt is
not indicated.
depending upon the value of the INTR_LEVEL bit (MR16.14). The events
which trigger an interrupt can be programmed via the Interrupt Control
Register located at address MR17.
No Connect. Do not connect to ground or supply.
DESCRIPTION
3.3V SUPPLY
GROUND
The pin will be forced high or low to signal an interrupt
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