QLX4300-S45 Datasheet, PDF (3/21 Pages) Intersil Corporation – Quad Lane Extender

QLx4300-S45
Pin Descrptions
PIN NAME PIN NUMBER
DESCRIPTION
DT
1
Detection Threshold. Reference DC current threshold for input signal power detection. Data
output OUT[k] is muted when the power of the equalized version of IN[k] falls below the
threshold. Tie to ground to disable electrical idle preservation and always enable the limiting
amplifier.
IN1[P,N]
2, 3
Equalizer 1 differential input, CML. The use of 100nF low ESL/ESR MLCC capacitor with at least
4GHz frequency response is recommended.
V_DD
4, 7, 10, 29, Power supply. 1.2V supply voltage. The use of parallel 100pF and 10nF decoupling capacitors to
32, 35
ground is recommended for each of these pins for broad high-frequency noise suppression.
IN2[P,N]
5, 6
Equalizer 2 differential input, CML. The use of 100nF low ESL/ESR MLCC capacitor with at least
4GHz frequency response is recommended.
IN3[P,N]
8, 9
Equalizer 3 differential input, CML. The use of 100nF low ESL/ESR MLCC capacitor with at least
4GHz frequency response is recommended.
IN4[P,N]
11, 12
Equalizer 4 differential input, CML. The use of 100nF low ESL/ESR MLCC capacitor with at least
4GHz frequency response is recommended.
IS1
IS2
GND
13
Impedance Select 1. CMOS logic input. When the voltage on this pin is LOW, the single-ended
input impedance of In1P and In1N each go above 200kΩ and powers down the channel. This pin
should be connected to the Fundamental Reset signal in PCI Express™. Otherwise, connect to
V_DD to hold the input impedance at 50Ω.
14
Impedance Select 2. CMOS logic input. When the voltage on this pin is LOW, the single-ended
input impedance of In2P and In2N each go above 200kΩ and powers down the channel. This pin
should be connected to the Fundamental Reset signal in PCI Express™. Otherwise, connect to
V_DD to hold the input impedance at 50Ω.
15
Ground
DI
DO
CP3[A,B,C]
CP4[A,B,C]
MODE
IS4
IS3
OUT4[N,P]
OUT3[N,P]
16
17
18, 19, 20
21, 22, 23
24
25
26
27, 28
30, 31
Serial data input, CMOS logic. Input for serial data stream to program internal registers
controlling the boost for all four equalizers. Synchronized with clock (CLK) on pin 46. Overrides
the boost setting established on CP control pins. Internally pulled down.
Serial data output, CMOS logic. Output of the internal registers controlling the boost for all four
equalizers. Synchronized with clock on pin 46. Equivalent to serial data input on DI but delayed
by 21 clock cycles.
Control pins for setting equalizer 3. CMOS logic inputs. Pins are read as a 3-digit number to set
the boost level. A is the MSB, and C is the LSB. Pins are internally pulled down through a 25kΩ
resistor.
Control pins for setting equalizer 4. CMOS logic inputs. Pins are read as a 3-digit number to set
the boost level. A is the MSB, and C is the LSB. Pins are internally pulled down through a 25kΩ
resistor.
Boost-level control mode input, CMOS logic. Allows serial programming of internal registers
through pins DI, ENB, and Clk when set HIGH. Resets all internal registers to zero and uses boost
levels set by CP pins when set LOW. If serial programming is not used, this pin should be
grounded.
Impedance Select 4. CMOS logic input. When the voltage on this pin is LOW, the single-ended
input impedance of In4P and In4N each go above 200kΩ and powers down the channel. This pin
should be connected to the Fundamental Reset signal in PCI Express™. Otherwise, connect to
V_DD to hold the input impedance at 50Ω.
Impedance Select 3. CMOS logic input. When the voltage on this pin is LOW, the single-ended
input impedance of In3P and In3N each go above 200kΩ and powers down the channel. This pin
should be connected to the Fundamental Reset signal in PCI Express™. Otherwise, connect to
V_DD to hold the input impedance at 50Ω.
Equalizer 4 differential output, CML. The use of 100nF low ESL/ESR MLCC capacitor with at least
4GHz frequency response is recommended.
Equalizer 3 differential output, CML. The use of 100nF low ESL/ESR MLCC capacitor with at least
4GHz frequency response is recommended.
3
FN6982.1
November 19, 2009