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GS1574 HD-LINX TM II
Adaptive Cable Equalizer
GS1574 Preliminary Data Sheet
Proprietary and Confidential
28854 - 2
December 2004
1 of 17
Features
SMPTE 292M, SMPTE 344M and SMPTE 259M
compliant
Automatic cable equalization
Multi-standard operation from 143Mb/s to 1.485Gb/s
Supports DVB-ASI at 270Mb/s
Small footprint (4mm x 4mm)
Pb-free and Green
Pin compatible with the GS9074 Cable Equalizer
Manual bypass (useful for low data rates with slow
rise/fall times)
Performance optimized for 270Mb/s and 1.485Gb/s
Typical maximum equalized length of Belden 1694A
cable: 140m at 1.485Gb/s, 350m at 270Mb/s
50
differential output (with internal 50 pull-ups)
Manual output mute or programmable mute based on
max cable length adjust
Single 3.3V power supply operation
Operating temperature range: 0C to +70C
Applications
SMPTE 292M, SMPTE 344M and SMPTE 259M Coaxial
Cable Serial Digital Interfaces.
Description
The GS1574 is a second-generation high-speed bipolar
integrated circuit designed to equalize and restore
signals received over 75
co-axial cable.
The GS1574 is designed to support SMPTE 292M,
SMPTE 344M and SMPTE 259M, and is optimized for
performance at 270Mb/s and 1.485Gb/s.
The GS1574 features DC restoration to compensate for
the DC content of SMPTE pathological test patterns.
A voltage programmable mute threshold (MCLADJ) is
included to allow muting of the GS1574 output when an
approximate selected cable length is reached for
SMPTE 259M signals. This feature allows the GS1574
to distinguish between low amplitude SD-SDI signals
and noise at the input of the device. The serial digital
outputs of the GS1574 may be forced to a mute state by
applying a voltage to the MUTE pin.
Power consumption is typically 270mW using a 3.3V
power supply. The GS1574 is lead-free, and the
encapsulation compound does not contain halogenated
flame retardant.
GS1574 Functional Block Diagram
CABLE LENGTH ADJUSTOR
CARRIER DETECT
MUTE
EQUALIZER
DC RESTORE
OUTPUT
AGC
MUTE
SDO
BYPASS
SDO
SDI
SDI
MCLADJ
GS1574 Preliminary Data Sheet
Proprietary and Confidential
28854 - 2
December 2004
2 of 17
Contents
Features ........................................................................................................................1
Applications...................................................................................................................1
Description ....................................................................................................................1
1. Pin Out ......................................................................................................................3
1.1 GS1574 Pin Assignment .................................................................................3
1.2 GS1574 Pin Descriptions ................................................................................4
2. Electrical Characteristics...........................................................................................5
2.1 Absolute Maximum Ratings ............................................................................5
2.2 DC Electrical Characteristics ..........................................................................5
2.3 AC Electrical Characteristics ...........................................................................6
2.4 Solder Reflow Profiles .....................................................................................7
3. Input / Output Circuits ...............................................................................................9
4. Detailed Description ................................................................................................11
4.1 Serial Digital Inputs .......................................................................................11
4.2 Cable Equalization ........................................................................................11
4.3 Programmable Mute Output ..........................................................................12
4.4 Mute ..............................................................................................................12
5. Application Information............................................................................................13
5.1 PCB Layout ...................................................................................................13
5.2 Typical Application Circuit A .........................................................................13
5.3 Typical Application Circuit B .........................................................................14
6. Package & Ordering Information.............................................................................15
6.1 Package Dimensions ....................................................................................15
6.2 Land Information ...........................................................................................16
6.3 Packaging Data .............................................................................................16
6.4 Ordering Information .....................................................................................16
7. Revision History ......................................................................................................17
GS1574 Preliminary Data Sheet
Proprietary and Confidential
28854 - 2
December 2004
3 of 17
1. Pin Out
1.1 GS1574 Pin Assignment
Figure 1-1: 16-Pin QFN
GS1574
(top view)
1
V
EE
_A
V
EE
_A
SDI
SDI
2
3
4
SDO
SDO
V
EE
_D
V
EE
_D
12
11
10
9
AGC
AGC
BYPASS
MCLADJ
5
7
6
8
V
CC
_A
MUTE
NC
V
CC
_D
13
14
15
16
Center Pad
(bottom of package, internally
bonded to VEE_A)
GS1574 Preliminary Data Sheet
Proprietary and Confidential
28854 - 2
December 2004
4 of 17
1.2 GS1574 Pin Descriptions
Table 1-1: GS1574 Pin Descriptions
Pin Number
Name
Timing
Type
Description
1, 4
VEE_A
Analog
Power
Most negative power supply for analog circuitry.
Connect to analog GND.
2, 3
SDI, SDI
Analog
Input
Serial digital differential input.
5, 6
AGC, AGC
Analog
External AGC capacitor.
Connect pin 5 and pin 6 together through a 1uF capacitor.
7
BYPASS
Not
Synchronous
Input
Forces the Equalizing and DC RESTORE stages into bypass mode
when HIGH. No equalization occurs in this mode.
8
MCLADJ
Analog
Input
Maximum cable length adjust.
Adjusts the approximate maximum amount of cable to be equalized
(from 0m to the maximum cable length). The output is muted (latched to
the last state) when the maximum cable length is achieved.
NOTE: MCLADJ is only recommended for data rates up to 360Mb/s.
9
VEE_D
Analog
Power
Most negative power supply for the digital circuitry and output buffer.
Connect to digital GND.
10, 11
SDO, SDO
Analog
Output
Equalized serial digital differential output.
12
VEE_D
Analog
Power
Most negative power supply for the digital circuitry and output buffer.
Connect to digital GND.
13
VCC_D
Analog
Power
Most positive power supply for the digital I/O pins of the device.
Connect to +3.3V DC.
14
MUTE
Not
Synchronous
Input
CONTROL SIGNAL INPUT
levels are LVCMOS/LVTTL compatible. (3.3V Tolerant)
When the MUTE pin is set HIGH by the application interface, the serial
digital output of the device will be forced to a steady state.
When the MUTE pin is set LOW, the serial digital output of the device
will be active.
15
NC
No Connect.
16
VCC_A
Analog
Power
Most positive power supply for the analog circuitry of the device.
Connect to +3.3V DC.
Center Pad
Power
Internally bonded to VEE_A.
GS1574 Preliminary Data Sheet
Proprietary and Confidential
28854 - 2
December 2004
5 of 17
2. Electrical Characteristics
2.1 Absolute Maximum Ratings
2.2 DC Electrical Characteristics
Parameter
Value
Supply Voltage
-0.5V to +3.6 V
DC
Input ESD Voltage (Human Body Model)
500V
Storage Temperature Range
-50C < T
s
< 125C
Input Voltage Range (any input)
-0.3 to (V
CC
+0.3)V
Operating Temperature Range
0C to 70C
Power Dissipation
300mW
Lead Temperature (soldering, 10 sec)
260C
Table 2-1: DC Electrical Characteristics
V
DD
= 3.3V, T
A
= 0C to 70C, unless otherwise shown
Parameter
Symbol
Conditions
Min
Typ
Max
Units
Test
Levels
Notes
Supply Voltage
V
CC
3.135
3.3
3.465
V
5%
Power Consumption
P
D
T
A
= 25C
265
mW
2
Supply Current
I
s
T
A
= 25C
80
mA
1
Output Common Mode
Voltage
V
CMOUT
T
A
= 25C
V
CC
-
V
SDO
/2
V
7
Input Common Mode
Voltage
V
CMIN
T
A
= 25C
1.75
V
8
Floating MCLADJ DC
Voltage
0m, T
A
= 25C
1.3
V
7
MCLADJ Range
T
A
= 25C
0.69
V
7
Mute Input Voltage
Required to Force Outputs
to Mute
V
Mute
Min to Mute
3.0
V
7
Mute Input Voltage
Required to Force Outputs
Active
V
Mute
Max to
Activate
2.0
V
7
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