19-0798; Rev 0; 4/07
KIT
ATION
EVALU
BLE
AVAILA
DVI/HDMI 2:4 TMDS Fanout Switch and
Cable Driver
General Description
The MAX3845 is a TMDS
®
2-to-4 fanout switch and
cable driver for multimonitor distribution of DVI™ or
HDMI™ signaling up to 1.65Gbps. Both inputs and out-
puts are standard TMDS signaling as per DVI and HDMI
standards. Because TMDS links are “point-to-point,”
buffering is required for fanout applications.
Four DVI/HDMI TMDS outputs are provided for fanout
distribution. Each TMDS output can be independently
sourced from either input or can be turned off. Each
TMDS input or output is composed of four differential
channels that can be arbitrarily assigned to the three
data signals and the 1/10th-rate clock. The data rate
depends on resolution, but it can vary from 250Mbps
(VGA) to 1.65Gbps (UXGA or 1080p/60).
Typical applications include multiroom display of the
same video source or industrial/commercial signage
applications such as airport monitors or trading room
floor displays. The MAX3845 includes selectable output
preemphasis that extends output cable reach up to an
additional 7m.
For DDC switching, use the companion MAX4814E 2:4
low-resistance CMOS crosspoint switch. DDC switching
is not required for applications that connect DDC to one
reference monitor only.
The MAX3845 can be configured to create a 2 x 8 or
4 x 4 switch (see the
Typical Operating Circuit
diagrams).
The MAX3845 is available in a 14mm
×
14mm, 100-pin
TQFP-EP package and operates over the -10°C to
+85°C temperature range.
Features
o
Two DVI/HDMI TMDS-Compatible Inputs and Four
DVI/HDMI TMDS-Compatible Outputs
o
Save Power by Turning Off Unused Outputs
o
Each Output Independently Selects Input 1 or
Input 2
o
Three Preemphasis Settings Extend Cable Reach
Up to 7m
o
Operation Up to 1.65Gbps
o
14mm x 14mm, 100-Pin TQFP Package with
Exposed Paddle for Heat Sinking
o
3.3V Power Supply
o
TMDS Data (x3) and Clock (x1) Can Be Arbitrarily
Assigned to the Four Identical Switched Paths (A,
B, C, and D)
MAX3845
Ordering Information
PART
MAX3845UCQ+
TEMP RANGE PIN-PACKAGE
-10°C to +85°C 100 TQFP-EP
PKG
CODE
C100E-3
+Denotes
a lead-free package.
EP = Exposed pad.
Applications
Digital Signage and Industrial Display
PC Monitor Distribution
Home A/V Receivers
DVI/HDMI Distribution Amplifiers
DVI/HDMI Crosspoint Switches
CONTROL
SIGNALS
Typical Operating Circuit
2:4 FANOUT/SWITCH APPLICATION
IN_SEL[1:4]
PREEMPH[1:4]
OUTPUT TO DISPLAY 1
OUTPUT TO DISPLAY 2
OUTPUT TO DISPLAY 3
OUTPUT TO DISPLAY 4
HOTPLUG[1:4]
BUFFER
2:4 CMOS
SWITCH x5 DDC DATA, DDC CLK,
HOTPLUG, 5V, GND, (CEC)
VIDEO SOURCE 1
VIDEO SOURCE 2
MAX3845
2:4 DVI/HDMI TMDS
FANOUT SWITCH AND
CABLE DRIVER
Pin Configuration appears at end of data sheet.
TMDS is a registered trademark of Silicon Image, Inc.
DVI is a trademark of Digital Display Working Group.
HDMI is a trademark of HDMI Licensing, LLC.
Typical Operating Circuits continued at end of data sheet.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
DVI/HDMI 2:4 TMDS Fanout Switch and
Cable Driver
MAX3845
ABSOLUTE MAXIMUM RATINGS
Supply Voltage Range (V
CC
) ................................-0.3V to +5.5V
Voltage Range at HOTPLUGx Pins ......................-0.3V to +6.0V
Voltage Range at LVTTL, LVCMOS, I/O Pins .......-0.3V to +5.5V
Voltage Range at CML Output Pins ......................-0.3V to +5.5V
Voltage Range at CML Input Pins
(CML short to GND duration < 1s)....................-0.3V to +4.0V
Voltage Between Any Input CML I/O
Complementary Pair ......................................................±3.3V
Voltage Range at LOSMUTE_EN ..........................-0.3V to +5.5V
Voltage Between Any Output CML I/O
Complementary Pair.......................................................±3.6V
Continuous Power Dissipation (T
A
= +70°C)
100-Pin TQFP-EP (derate 45.5mW/°C
above +70°C) ............................................................3636mW
Operating Junction Temperature .....................-55°C to +150°C
Storage Temperature Range ............................-55°C to +150°C
Die Attach Temperature ..................................................+400°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
CC
= 3.0V to +3.6V, T
A
= -10°C to +85°C. Typical values are at V
CC
= +3.3V, external terminations = 50Ω ±1%, TMDS rate =
250Mbps to 1.65Gbps, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Power-Supply Current
Supply-Noise Tolerance
SKIN-EFFECT EQUALIZER PEAKING
Fixed Rx Equalizer
Compensation
Settable Tx Preemphasis
JITTER PERFORMANCE
0dB cable loss, no
preemphasis
200 back
termination
3dB cable loss, +3dB
preemphasis
6dB cable loss, +6dB
preemphasis
0dB cable loss, no
preemphasis
No back
termination
3dB cable loss, +3dB
preemphasis
6dB cable loss, +6dB
preemphasis
Residual Random Jitter (Note 3)
CML INPUTS (SOURCE SIDE)
Differential-Input Voltage Swing
Common-Mode Input Voltage
Input Voltage When Disconnected
V
ID
V
CM
At cable input
400
V
CC
- 1000
V
CC
- 10
2000
V
CC
V
CC
+ 10
mV
P-P
mV
Measured with source T
r
/T
f
= 250ps
0.04
0.05
0.07
0.07
0.08
0.10
1.5
0.12
0.12
0.12
UI
0.2
0.2
0.2
2
ps
RMS
Gain at 825MHz
PREEMPHx pin = low
PREEMPHx pin = open
PREEMPHx pin = high
1
0
3
6
dB
SYMBOL
I
CC
CONDITIONS
PREEMPH[1:4] = high, OUT_LEVEL = high,
current into V
CC
pins, 1200mV
P-P
= V
IN
DC to 500kHz
MIN
TYP
454
50
MAX
626
UNITS
mA
mV
P-P
Residual Deterministic Jitter
(Measured at end of cable
having ideal skin-effect loss
and connectors, e.g., Gore Twin
Coax, Amphenol Skewclear
Twinax, with SMA connectors)
(Note 2)
2
_______________________________________________________________________________________
DVI/HDMI 2:4 TMDS Fanout Switch and
Cable Driver
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 3.0V to +3.6V, T
A
= -10°C to +85°C. Typical values are at V
CC
= +3.3V, external terminations = 50Ω ±1%, TMDS rate =
250Mbps to 1.65Gbps, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Input Resistance
Input LOS/Mute Threshold
Input LOS/Mute Response Time
Input Return Loss
CML OUTPUTS (CABLE SIDE)
No preemphasis, no back termination,
OUT_LEVEL = low
No preemphasis, 200
OUT_LEVEL = high
back termination,
900
825
V
CC
- 10
V
CC
- 10
75
90
12
Worst case among A, B, C, and D of an
output
V
IH
V
IL
All except IN_SELx pins
IN_SELx pins
V
IH(MIN)
< V
IN
< V
IH(MAX)
V
IL(MIN)
< V
IN
< V
IL(MAX)
Typical input 30k
All except
OUT_LEVEL pin
OUT_LEVEL pin
HOTPLUGx Input High Voltage
HOTPLUGx Input Low Voltage
to GND
V
CC
- 0.2
2.0
1.0
0.8
100
150
500
5.5
1.5
V
μA
V
35
1050
925
1200
mV
P-P
1050
V
CC
+ 10
V
CC
+ 10
140
40
60
ps
mV
SYMBOL
R
IN
Single-ended
Differential peak-peak
Deassert mute
Assert mute
Differential,
1.6GHz
CONDITIONS
MIN
45
TYP
50
150
1.2
0.6
19
MAX
55
mV
μs
dB
UNITS
MAX3845
Differential-Output Voltage Swing
V
OD
Output-Voltage High
Output Voltage During Power-
Down
Rise/Fall Time
Intrapair Skew
Interpair Skew
CONTROL INTERFACE
LVTTL Input High Voltage
LVTTL Input Low Voltage
LVTTL Input High Current
LVTTL Input Low Current
V
OH
V
OFF
Single-ended, no back termination
Single-ended, PWRDWN_x = low or
V
CC
= 0V
20% to 80% (T
A
= 0°C to +85°C)
Note 1:
AC specifications are guaranteed by design and characterization.
Note 2:
Test pattern is a 2
10
- 1 PRBS + 20 ones + 2
10
- 1 PRBS (inverted) + 20 zeros.
Note 3:
Test pattern is a 1111 0000 pattern at 1.65Gbps.
_______________________________________________________________________________________
3
DVI/HDMI 2:4 TMDS Fanout Switch and
Cable Driver
MAX3845
Typical Operating Characteristics
(Typical values are at V
CC
= +3.3V, T
A
= +25°C, data pattern = 2
10
- 1 PRBS + 20 ones + 2
10
- 1 PRBS (inverted) + 20 zeros, unless
otherwise noted.)
SUPPLY CURRENT
vs. AMBIENT TEMPERATURE
MAX3845 toc01
SUPPLY CURRENT
vs. AMBIENT TEMPERATURE
MAX3845 toc02
OUTPUT EYE DIAGRAM AT 1.65Gbps
SHORT LOW-LOSS SMA CABLE
MAX3845 toc03
500
480
460
I
CC
(mA)
440
420
400
380
360
340
-10
5
20
35
50
65
80
AMBIENT TEMPERATURE (°C)
6dB PREEMPHASIS
3dB PREEMPHASIS
0dB PREEMPHASIS
OUT_LEVEL = LOW,
ALL INPUTS/OUTPUTS ACTIVE,
PREEMPHASIS SAME ON ALL
OUTPUT CHANNELS
500
480
460
I
CC
(mA)
440
420
6dB PREEMPHASIS
400
3dB PREEMPHASIS
380
0dB PREEMPHASIS
360
340
-10
5
20
35
50
65
80
OUT_LEVEL = HIGH,
ALL INPUTS/OUTPUTS ACTIVE,
PREEMPHASIS SAME ON ALL
OUTPUT CHANNELS
0dB PREEMPHASIS
200Ω BACK TERMINATION
150mV/div
100ps/div
AMBIENT TEMPERATURE (°C)
OUTPUT EYE DIAGRAM AT 2.25Gbps
SHORT LOW-LOSS SMA CABLE
MAX3845 toc04
OUTPUT EYE DIAGRAM AT 1.65Gbps
6dB LOSS, 24AWG, 25ft TWIN-AX CABLE
MAX3845 toc05
OUTPUT EYE DIAGRAM AT 2.25Gbps
6dB LOSS, 24AWG, 25ft TWIN-AX CABLE
MAX3845 toc06
0dB PREEMPHASIS
200Ω BACK TERMINATION
6dB PREEMPHASIS
200Ω BACK TERMINATION
6dB PREEMPHASIS
200Ω BACK TERMINATION
150mV/div
150mV/div
150mV/div
80ps/div
100ps/div
80ps/div
OUTPUT EYE DIAGRAM AT 1.65Gbps
THROUGH 2m DVI TO HDMI CABLE
MAX3845 toc07
JITTER vs. INPUT-SIDE CABLE LOSS
AT 825 MHz
140
120
JITTER (ps
P-P
)
DATA RATE = 1.65Gbps
200Ω BACK TERMINATION
MAX3845 toc08
JITTER vs. OUTPUT-SIDE CABLE LOSS
AT 825 MHz
DATA RATE = 1.65Gbps
200Ω BACK TERMINATION
3dB PREEMPHASIS
0dB PREEMPHASIS
MAX3845 toc09
6dB PREEMPHASIS
200Ω BACK TERMINATION
160
120
100
80
60
40
20
0
6dB PREEMPHASIS
150mV/div
100
80
60
40
20
0
0
2
4
CABLE LOSS (dB)
6
8
JITTER (ps
P-P
)
100ps/div
0
2
4
CABLE LOSS (dB)
6
8
4
_______________________________________________________________________________________
DVI/HDMI 2:4 TMDS Fanout Switch and
Cable Driver
Typical Operating Characteristics (continued)
(Typical values are at V
CC
= +3.3V, T
A
= +25°C, data pattern = 2
10
- 1 PRBS + 20 ones + 2
10
- 1 PRBS (inverted) + 20 zeros, unless
otherwise noted.)
DIFFERENTIAL-INPUT RETURN LOSS
vs. FREQUENCY
MAX3845 toc10
MAX3845
TEMP VOLTAGE
vs. JUNCTION TEMPERATURE
MAX3845 toc11
POWER DISSIPATION
vs. AMBIENT TEMPERATURE
ALL INPUTS/OUTPUTS ACTIVE,
PREEMPHASIS SAME ON ALL
OUTPUT CHANNELS
MAX3845 toc12
0
-5
-10
GAIN (dB)
1.6
1.5
1.4
TEMP (V)
1.3
1.2
1.1
1.0
0.9
0.8
3000
2500
POWER DISSIPATION (mW)
2000
1500
1000
500
0
0dB PREEMPHASIS
OUT_LEVEL = LOW
6dB PREEMPHASIS
OUT_LEVEL = HIGH
-15
-20
-25
-30
-35
-40
0
500
1000
1500
2000
2500
3000
FREQUENCY (MHz)
-10
10
30
50
70
90
110 130 150
-10
5
20
35
50
65
80
JUNCTION TEMPERATURE (°C)
AMBIENT TEMPERATURE (°C)
Pin Description
PIN
1, 4, 7, 10,
97, 100
NAME
V
CC1
IN1_B+,
IN1_C+,
IN1_D+,
IN1_A+
IN1_B-,
IN1_C-,
IN1_D-,
IN1_A-
FUNCTION
Positive Power-Supply Connection. Powers input channel 1 and output channels 1 and 2.
2, 5, 8, 98
Noninverting TMDS CML Input, Channel 1
3, 6, 9, 99
Inverting TMDS CML Input, Channel 1
11
12
13
14
Power-Down, LVTTL/LVCMOS Input. Force high or leave open to power down input channel 1. Force
PWRDWN_1 low to enable input channel 1. The MAX3845 powers down if both PWRDWN_1 and PWRDWN_2 are
forced high or left open.
V
CC3
LOSMUTE_EN
TEMP
Positive Power-Supply Connection. Powers the temp-sense circuitry.
LOS MUTE Enable Input. Connect to V
CC
for typical operation. Connect to GND to disable the LOS
MUTE function.
Junction Temperature Sensor. Attach a ground-referenced voltage DMM to this pin to measure the
die’s junction temperature (see the V
CC3
pin description). Leave open if not used.
15
16, 19, 22,
25, 26, 29
Power-Down, LVTTL/LVCMOS Input. Force high or leave open to power down input channel 2. Force
PWRDWN_2 low to enable input channel 2. The MAX3845 powers down if both PWRDWN_1 and PWRDWN_2 are
forced high or left open.
V
CC2
Positive Power-Supply Connection. Powers input channel 2 and output channels 3 and 4.
_______________________________________________________________________________________
5
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