19-5143; Rev 1; 1/12
TION KIT
EVALUA BLE
AVAILA
Low-Capacitance VGA 2:2 Dual-Graphics
Crossover Switch
General Description
The MAX14885E integrates high-bandwidth analog
switches, level-translating buffers, and level-translating
FET switches. The device implements a complete 2:2
dual-graphics crossover solution for VGA signal switch-
ing. The MAX14885E provides 12 very high-frequency
700MHz (typ) SPST switches for RGB signals, four low-
frequency clamping switches for display data channel
(DDC) signals, two pairs of level-translating buffers for
the HSYNC and VSYNC signals, and integrated extend-
ed ESD protection. The MAX14885E is used to select
one of two sources to either of two destinations (see the
Typical Operating Circuit)
within a laptop computer.
Horizontal and vertical synchronization (SH_/SV_) inputs
feature level-shifting buffers to support low-voltage con-
trollers and standard 5V TTL-level monitors. DDC, con-
sisting of SDA_ and SCL_, are FET switches that protect
the low-voltage VGA source from potential damage from
high-voltage presence on the monitor while reducing
capacitive load.
All 14 output terminals of the MAX14885E feature high-
ESD protection to
Q15kV
Human Body Model (HBM)
and
Q6kV
IEC 61000-4-2 Contact Discharge (see the
Pin
Description).
All other pins are protected to
Q2kV
HBM.
The MAX14885E is specified over the extended -40NC to
+85NC temperature range, and is available in a 40-pin
TQFN (5mm x 5mm) package.
S
Low Quiescent Current
≤
5µA (max)
S
Low 5I (typ) On-Resistance (RGB Signals)
S
High Bandwidth, 700MHz (typ), RGB
S
DDC Level Shifting, Isolation with Internal Pullup
Features
MAX14885E
Termination, and Protection
Buffering
S
Horizontal and Vertical Sync Level Shifting and
S
Inputs Compatible with V
L
, Outputs TTL
Compatible
S
Source/Sink ±10mA on Each SH_, SV_ Output
S
Independent Selectable Logic Inputs for Switching
S
High ESD Protection on Outputs
±15kV ESD HBM
±6kV IEC 61000-4-2 Contact Discharge
S
Small, 40-Pin TQFN (5mm x 5mm) Package
Applications
Notebook Computer—Switchable Graphics
Ordering Information
PART
MAX14885EETL+
TEMP RANGE
-40NC to +85NC
PIN-PACKAGE
40 TQFN-EP*
+Denotes
a lead(Pb)-free/RoHS-compliant package.
*EP
= Exposed pad.
Typical Application Circuit
+3.3V
1µF
+5V
1µF
V
L
3
MXM
MODULE
2
2
V
CC
RED1, GRN1, BLU1
SH1, SV1
SDA1, SCL1
3
2
2
VGA
PORT
REDA, GRNA, BLUA
SHA, SVA
SDAA, SCLA
MAX14885E
3
INTERNAL
GRAPHICS
2
2
REDB, GRNB, BLUB
SHB, SVB
SDAB, SCLB
EN
RED2, GRN2, BLU2
SH2, SV2
SDA2, SCL2
3
2
2
DOCKING
STATION
S00 S01 S10 S11
GPIO
GND
_______________________________________________________________
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.
Low-Capacitance VGA 2:2 Dual-Graphics
Crossover Switch
MAX14885E
ABSOLUTE MAXIMUM RATINGS
(Voltages referenced to GND.)
V
CC
........................................................................ -0.3V to +6V
V
L
.......................................................................... -0.3V to +6V
RED_, GRN_, BLU_, SCL1, SCL2, SDA1,
SDA2, SH1, SH2, SV1, SV2 ................. -0.3V to (V
CC
+ 0.3V)
SCLA, SCLB, SDAA, SDAB, SHA, SHB,
SVA, SVB, S00, S01, S10, S11, EN ........ -0.3V to (V
L
+ 0.3V)
Continuous Current Through RED_,
GRN_, BLU_ Switches ................................................
Q50mA
Continuous Current Through SDA_, SCL_ Switches .....
Q50mA
Peak Current Through All Switches
(pulsed at 1ms, 10% duty cycle) ..............................
Q100mA
Continuous Power Dissipation (Multilayer Board, T
A
= +70NC):
40-Pin TQFN (derate 35.7mW/NC above +70NC) .......2857mW
Operating Temperature Range .......................... -40NC to +85NC
Storage Temperature Range............................ -65NC to +150NC
Junction Temperature .....................................................+150NC
Soldering Temperature (reflow) ......................................+260NC
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.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
TQFN
Junction-to-Ambient Thermal Resistance (q
JA
) ..........28°C/W
Junction-to-Case Thermal Resistance (q
JC
) .................2°C/W
Note 1:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-
layer board. For detailed information on package thermal considerations, refer to
www.maxim-ic.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(V
CC
= +4.5V to +5.5V, V
L
= +2.3V to V
CC
, T
A
= -40NC to +85NC, unless otherwise noted. Typical values are at V
CC
= +5.0V,
V
L
= +3.3V and T
A
= +25NC.) (Note 2)
PARAMETER
Supply Voltage
Logic Supply Voltage
V
CC
Supply Current
SYMBOL
V
CC
V
L
I
CC
V
L
P
V
CC
V
CC
= +5.5V, V
L
= +3.6V, V
EN
= 0V,
V
SHA,
V
SHB,
V
SVA,
V
SVB
= 0V or V
L
V
CC
= +5.5V, V
L
=
+3.6V, SCL_ and
SDA_ unconnected
V
EN
, V
SHA
, V
SHB
,
V
SVA
, V
SVB
= 0V
V
EN
, V
SHA,
V
SHB
,
V
SVA
, V
SVB
= V
L
CONDITIONS
MIN
4.5
2.3
3.3
0.2
0.2
0.3
5
TYP
MAX
5.5
5.5
5
5
0.5
8
1
0.5
-1
25
20
3
1
+1
UNITS
V
V
FA
FA
mA
I
I
I
FA
I
kI
kI
V
L
Supply Current
I
L
On-Resistance (RED_, GRN_,
BLU_)
On-Resistance Match (RED_,
GRN_, BLU_)
On-Resistance Flatness (RED_,
GRN_, BLU_)
Leakage Current (RED_, GRN_,
BLU_)
On-Resistance (SDA_, SCL_)
V
CC
Pullup Resistor (SDA1,
SDA2, SCL1, SCL2)
V
L
Pullup Resistor (SDAA, SDAB,
SCLA, SCLB)
RHF
ON
DR
ON
V
IN
= +0.7V, I
IN
= +10mA
0V
P
V
IN
P
+0.7V, I
IN
= -10mA
R
FLAT(ON)
0V
P
V
IN
P
+0.7V, I
IN
= -10mA
I
LK
RDDC
ON
V
EN
= 0V
V
IN
= +0.7V, I
IN
=
Q10mA
Resistor to V
CC
Resistor to V
L
2
______________________________________________________________________________________
Low-Capacitance VGA 2:2 Dual-Graphics
Crossover Switch
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +4.5V to +5.5V, V
L
= +2.3V to V
CC
, T
A
= -40NC to +85NC, unless otherwise noted. Typical values are at V
CC
= +5.0V,
V
L
= +3.3V and T
A
= +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
0.25 x
V
L
0.55 x
V
L
0.6 x
V
L
100
100
1
1
TYP
MAX
UNITS
DIGITAL INPUTS (EN, S00, S01, S10, S11, SHA, SHB, SVA, SVB)
Input Threshold Low
V
IL
+2.3V
P
V
L
P
V
CC
+3.3V
P
V
L
P
V
CC
Input Threshold High
V
IH
+2.3V
P
V
L
P
+3.3V
Input Hysteresis
V
L
Pulldown Resistor
Enable Time
Select Time
t
EN
t
SEL
V
HYST
+2.3V
P
V
L
P
V
CC
Resistor to V
L
(EN, S00, S01, S10, S11,
SHA, SHB, SVA, SVB)
R
L
= 2.2kI, C
L
= 10pF, Figure 1 (EN)
R
L
= 2.2kI, C
L
= 10pF, Figure 1 (S00,
S01, S10, S11)
I
OUT
= +10mA, V
CC
= +4.5V
I
OUT
= -10mA, V
CC
= +4.5V
R
L
= 2.2kI, C
L
= 10pF, Figure 2 (Note 3)
R
S
= R
L
= 50I
f = 10MHz, R
S
= R
L
= 50I,
0V
P
V
BIAS
P
+0.7V, Figure 3
R
S
= R
L
= 50I, f = 50MHz, Figure 3
V
EN
= 0V, RED_, GRN_, BLU_ to GND,
f = 1MHz, REDA/REDB to RED1/RED2,
GRNA/GRNB to GRN1/GRN2, BLUA/BLUB
to BLU1/BLU2
f = 1MHz, REDA/REDB to RED1/RED2,
GRNA/GRNB to GRN1/GRN2, BLUA/BLUB
to BLU1/BLU2 (Note 3)
3
2
700
0.7
-40
4
V
MAX14885E
V
mV
kI
Fs
Fs
DIGITAL OUTPUTS (SH1, SV1, SH2, SV2)
Output-Voltage Low
Output-Voltage High
Rise/Fall Time
RGB AC PERFORMANCE
Bandwidth
On-Loss
Crosstalk (RED_, GRN_, BLU_)
f
BW
MHz
dB
dB
V
OL
V
OH
t
R/F
0.6
V
V
ns
Off-Capacitance
C
OFF
3.5
pF
On-Capacitance
ESD PROTECTION
RED1, GRN1, BLU1, RED2,
GRN2, BLU2, SDA1, SCL1,
SDA2, SCL2, SH1, SV1, SH2,
SV2
All Other Terminals
C
ON
10
12
pF
HBM (Note 4)
IEC 61000-4-2 Contact Discharge (Note 4)
HBM
Q15
kV
Q6
Q2
kV
Note 2:
The device is 100% production tested at T
A
= +25NC. Limits over the operating temperature range are guaranteed by
design and not production tested.
Note 3:
Guaranteed by design. Not production tested.
Note 4:
Tested terminal to GND, 1FF bypass capacitors on V
CC
and V
L
.
_______________________________________________________________________________________
3
Low-Capacitance VGA 2:2 Dual-Graphics
Crossover Switch
MAX14885E
Test Circuits/Timing Diagrams
V
CC
V
CC
V
N
SHA, SHB
SVA, SVB
EN, S00,
LOGIC
INPUT
S01, S10,
S11
V
OUT
MAX14885E
GND
SWITCH
OUTPUT
0V
50%
50%
SH1, SH2
SV1, SV2
R
L
C
L
V
OUT
LOGIC
INPUT
V
CC
0V
50%
t
R
< 5ns
t
F
< 5ns
50%
t
SEL
t
EN
,
t
SEL
C
L
INCLUDES FIXTURE AND STRAY CAPACITANCE.
Figure 1. Enable/Select Time
R
L
= 2.2kΩ
C
L
= 10pF
V
CC
90%
90%
0V
SH1, SV1,
SH2, SV2
10%
t
R
t
F
10%
OSCILLOSCOPE WITH 1GHz OR BETTER PERFORMANCE
Figure 2. Rise/Fall Time
+3.3V
1
µ
F
+5V
1
µ
F
NETWORK
ANALYZER
RED1,
GRN1,
BLU1
REDB,
GRNB,
BLUB
V
IN
50
Ω
50
Ω
INSERTION LOSS = 20log
CROSSTALK = 20log
V
OUT
MEAS
50
Ω
REF
50
Ω
V
L
GND OR V
L
EN, S00, S01,
S10, S11
REDA,
GRNA,
BLUA
50
Ω
V
CC
MAX14885E
( )
( )
V
OUT
V
IN
V
OUT
V
IN
GND
MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS.
INSERTION LOSS IS MEASURED BETWEEN RED1 AND REDA OR REDB ON EACH SWITCH.
CROSSTALK IS MEASURED FROM ONE CHANNEL TO THE OTHER CHANNEL.
SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED.
Figure 3. Insertion Loss and Crosstalk
4
______________________________________________________________________________________
Low-Capacitance VGA 2:2 Dual-Graphics
Crossover Switch
Typical Operating Characteristics
(V
CC
= +5.0V, V
L
= +3.3V, T
A
= +25NC, unless otherwise noted.)
R
ON
vs. V
REDA
*
(RGB SWITCHES)
MAX14885E toc01
MAX14885E
R
ON
vs. V
SDAA
*
(DDC SWITCHES)
MAX14885E toc02
HV BUFFER OUTPUT-VOLTAGE HIGH
vs. TEMPERATURE
I
OUT
= -10mA
MAX14885E toc03
10
9
8
7
R
ON
(
Ω
)
6
5
4
3
2
1
0
0
*REDA, BLUA, GRNA, REDB, BLUB, GRNB ARE
INTERCHANGABLE
T
A
= +85°C
50
40
30
20
10
0
0
*SDAA, SDAB, SCLA, SCLB ARE INTERCHANGABLE
5.2
5.0
OUTPUT-VOLTAGE HIGH (V)
4.8
4.6
4.4
4.2
4.0
-40
R
ON
(
Ω
)
T
A
= +25°C
T
A
= -40°C
T
A
= +25°C
T
A
= -40°C
T
A
= +85°C
0.2
0.4
0.6
0.8
1.0
0.5
1.0
1.5
2.0
2.5
-15
10
35
60
85
V
REDA
(V)
V
SDAA
(V)
TEMPERATURE (°C)
HV BUFFER OUTPUT-VOLTAGE LOW
vs. TEMPERATURE
MAX14885E toc04
SUPPLY CURRENT vs. TEMPERATURE
MAX14885E toc05
SUPPLY CURRENT vs. TEMPERATURE
45
40
SUPPLY CURRENT (µA)
35
30
25
20
15
10
5
0
I
OUT
= +10mA
V
S00
- V
S11
= 0V, V
EN
= 0V
V
S00
- V
S11
= 0V, V
EN
= V
L
, V
L
= 3.6V
OUTPUT-VOLTAGE LOW (V)
0.8
0.6
0.4
0.2
0
-40
-15
10
35
60
4
SUPPLY CURRENT (µA)
I
CC
3
2
1
0
I
L
I
CC
I
L
85
-40
-15
10
35
60
85
-40
-15
10
35
60
85
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
ON-RESPONSE vs. FREQUENCY
MAX14885E toc07
CROSSTALK vs. FREQUENCY
-10
-20
CROSSTALK (dB)
-30
-40
-50
-60
-70
-80
-90
-100
MAX14885E toc08
0
-1
-2
ON-RESPONSE (dB)
-3
-4
-5
-6
-7
-8
-9
-10
1
10
100
0
1000
1
10
100
1000
FREQUENCY (MHz)
FREQUENCY (MHz)
_______________________________________________________________________________________
MAX14885E toc06
1.0
5
50
5
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