MAXIM MAX4885AEETI+

19-5022; Rev 0; 10/09
TION KIT
EVALUA BLE
IL
AVA A
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
Features
The MAX4885AE integrates high-bandwidth analog
switches, level-translating buffers, and level-translating
FET switches to implement a complete 2:1 multiplexer
for VGA signals. The device provides three very highfrequency 900MHz (typ) SPDT switches for RGB signals,
two low-frequency clamping switches for the DDC signals, a pair of level-translating buffers for the H_ and V_
signals, and integrated extended ESD protection.
S Low 5I (typ) On-Resistance (R_, G_, B_ Signals)
Horizontal and vertical synchronization (H_/V_) inputs
feature level-shifting buffers to support low-voltage
controllers and standard 5V-TTL-compatible monitors,
meeting the VESA requirement. Display Data Channel
(DDC), consisting 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.
S Q15kV ESD HBM
All seven output terminals of the MAX4885AE feature
high-ESD protection to Q15kV Human Body Model
(HBM) (see the Pin Description). All other pins are protected to Q2kV Human Body Model (HBM).
The MAX4885AE is specified over the extended -40NC to
+85NC temperature range, and is available in a spacesaving, 28-pin, 4mm x 4mm TQFN package.
S Low 5.5pF (typ) On-Capacitance (R_, G_, B_
Signals)
S Independent, Selectable Logic Inputs for
Switching
S Similar Pin Configuration to MAX4885
S Ultra-Small, 28-Pin (4mm x 4mm) TQFN Package
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX4885AEETI+
-40NC to +85NC
28 TQFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Typical Operating Circuit
+3.3V
+5V
1µF
KVM for Servers
1µF
VCC
MAX4885AE
Applications
Notebook Computer—MXM/Switchable Graphics
VL
3
MXM
MODULE
2
2
3
INTERNAL
GRAPHICS
CPU
2
2
R1, G1, B1
R0, G0, B0
H0, V0
H1, V1
SDA0, SCL0
SDA1, SCL1
3
2
2
VGA
PORT
R2, G2, B2
H2, V2
SDA2, SCL2
SEL1
SEL2
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.
MAX4885AE
General Description
MAX4885AE
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND unless otherwise noted.)
VCC. .........................................................................-0.3V to +6V
VL.............................................................. -0.3V to (VCC + 0.3V)
R_, G_, B_, H0, V0, SDA0, SCL0.............. -0.3V to (VCC + 0.3V)
H1, H2, V1, V2, SDA1, SDA2, SCL1,
SCL2, SEL1, SEL2.................................... -0.3V to (VL + 0.3V)
Continuous Current through R_, G_, B_ Switches........... Q50mA
Continuous Current through SDA_, SCL_ Switches ....... Q50mA
Continuous Current into SEL1, SEL2, H1, H2, V1, V2..... Q20mA
Peak Current through all Switches
(pulsed at 1ms, 10% duty cycle)................................ Q100mA
Continuous Power Dissipation (TA = +70NC)
28-Pin TQFN (derate 28.6mW/NC above +70NC).....2285.7mW
Junction-to-Ambient Thermal Resistance (BJA) (Note 1)
28-Pin TQFN..................................................................35NC/W
Junction-to-Ambient Thermal Resistance (BJC) (Note 1)
28-Pin TQFN....................................................................3NC/W
Operating Temperature Range........................... -40NC to +85NC
Storage Temperature Range............................. -65NC to +150NC
Junction Temperature.................................................... +150NC
Lead Temperature (soldering, 10s).................................+300NC
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to http://www.maxim-ic.com/thermaltutorial.
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
(VCC = +4.5V to +5.5V, VL = +2.2V to VCC, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.)
PARAMETER
Supply Voltage
SYMBOL
CONDITIONS
VCC
Logic Supply Voltage
VL
VL P VCC
VCC Supply Current
ICC
VCC = +5.5V, VL = +3.6V,
SEL_ = H1 = H2 = V1 = V2 = GND
IL
VCC = +5.5V, VL = +3.6V,
SEL_ = H1 = H2 = V1 = V2 = GND
VL Supply Current
MAX
UNITS
+4.5
MIN
TYP
+5.5
V
+2.2
VCC
V
5
FA
1
FA
8
I
1
I
1
I
+1
FA
2
ANALOG SWITCHES
On-Resistance (R_, G_, B_)
On-Resistance Match (R_, G_,
B_)
On-Resistance Flatness
(R_, G_, B_)
Off Leakage Current (R_, G_, B_)
On-Resistance (SDA_, SCL_)
Off-Leakage Current
(SDA_, SCL_)
2
R-HF-ON
DRON
5
VIN = +0.7V, IIN = Q10mA
0 P VIN P +0.7V, IIN = -10mA
RFLAT(ON) 0 P VIN P +0.7V, IIN = -10mA
IOFF
R-DDCON
IOFF
VR_, VG_, VB_ = 0V or VCC
VIN = +0.7V, IIN = Q10mA
VSDA_, VSCL_ = 0V or VL,
VCC = VL = +5V
0.5
-1
15
-1
I
+1
FA
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
MAX4885AE
ELECTRICAL CHARACTERISTICS (continued)
(VCC = +4.5V to +5.5V, VL = +2.2V to VCC, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DIGITAL INPUTS (SEL_, H1, H2, V1, V2)
Input Threshold Low
VIL
Input Threshold High
VIH
Input Hysteresis
Input Leakage Current
SEL_ Enable/Disable Time
0.25 x VL
0.55 x
VL
VHYST
100
IL
tON, tOFF
V
-1
mV
+1
300
RL= 2.2kI, CL = 10pF, Figure 1
V
FA
ns
DIGITAL OUTPUTS (H0, V0)
Output-Voltage Low
VOL
IOUT = 8mA, VCC = +4.5V
Output-Voltage High
VOH
Rise/Fall Time
tR, tF
IOUT = -8mA, VCC = +4.5V
RL= 2.2kI, CL = 10pF, Figure 2
fMAX
RS = RL = 50I
900
MHz
ILOSS
f = 10MHz, RS = RL = 50I, 0 P V P +0.7V,
Figure 3
0.4
dB
f = 50MHz, RS = RL = 50I, Figure 3
-40
dB
2.5
pF
2.4
0.8
V
V
8
ns
RGB AC PERFORMANCE Bandwidth
On-Loss
Crosstalk R_, G_, B_
VCT
Off-Capacitance
COFF
f = 1MHz, R0 to R1/R2, G0 to G1/G2, B0
to B1/B2 (Note 2)
On-Capacitance
CON
f = 1MHz, R0 to R1/R2, G0 to G1/G2, B0
to B1/B2 (Note 2)
5.5
R0, G0, B0, SDA0, SCL0, H0, V0
VESD
HBM (Notes 2, 3)
Q15
kV
R0, G0, B0, SDA0, SCL0, H0, V0
VESD
IEC 61000-4-2 Contact (Notes 2, 3)
Q8
kV
All Other Terminals
VESD
HBM (Note 2)
Q2
kV
8
pF
ESD PROTECTION Note 2: Guaranteed by design. Not production tested.
Note 3: Tested terminal to GND, 1µF bypass capacitors on VCC and VL.
3
Typical Operating Characteristics
(VCC = +5.0V, VL = +3.3V, TA = 25°C, unless otherwise noted.)
7
6
RON (Ω)
RON (Ω)
40
TA = +25°C
5
4
VL = +3.3V
30
TA = +85°C
20
TA = -40°C
TA = +85°C
TA = +25°C
3
2
VL = +5V
TA = +25°C
TA = -40°C
10
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
0
HV BUFFER OUTPUT-VOLTAGE LOW
vs. TEMPERATURE
SUPPLY CURRENT
vs. TEMPERATURE
0.4
4.0
ICC
3
2
1
0
0
-15
10
35
60
0
MAX4885AE toc05
4
0.2
-40
-1
-2
ON-RESPONSE (dB)
0.6
4.4
85
ON-RESPONSE vs. FREQUENCY
5
SUPPLY CURRENT (µA)
0.8
4.6
TEMPERATURE (°C)
VSDA0 (V)
IOUT = 8mA
4.8
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
VRO (V)
MAX4885AE toc04
1.0
5.0
TA = -40°C
0
0
IOUT = 8mA
4.2
1
0
5.2
MAX4885AE toc03
TA = +85°C
*SDA0, SCL0 ARE INTERCHANGEABLE
IL
MAX4885AE toc06
8
HV BUFFER OUTPUT-VOLTAGE HIGH
vs. TEMPERATURE
OUTPUT-VOLTAGE HIGH (V)
*R0, G0, B0 ARE INTERCHANGEABLE
9
50
MAX4885AE toc01
10
RON vs. VSDA0*
(DDC SWITCHES)
MAX4885AE toc02
RON vs. VRO*
(RGB SWITCHES)
OUTPUT-VOLTAGE LOW (V)
-3
-4
-5
-6
-7
-8
-9
-40
-15
10
35
60
85
-40
TEMPERATURE (°C)
-15
10
35
60
85
TEMPERATURE (°C)
MAX4885AE toc07
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
1
10
100
FREQUENCY (MHz)
4
-10
1
10
100
FREQUENCY (MHz)
CROSSTALK vs. FREQUENCY
0
CROSSTALK (dB)
MAX4885AE
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
1000
1000
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
VL
RL = 2.2kΩ
CL = 10pF
50%
0V
50%
SEL1,
SEL2
tOFF
VCC
80%
80%
RL = 2.2kΩ
CL = 10pF
tON
50%
0V
VCC
0V
50%
H0, V0 20%
20%
tR
tR
H0, V0
Figure 1. Enable/Disable Time
+3.3V
Figure 2. Rise/Fall Time
+5V
1µ F
1µ F
VL
GND OR VL
SEL1, SEL2
VCC
R0, G0, B0
MAX4885AE
R1, G1, B1
50Ω
R2, G2, B2
GND
NETWORK
ANALYZER
50Ω
VIN
50Ω
INSERTION-LOSS = 20log
CROSSTALK = 20log
VOUT
MEAS
50Ω
REF
( )
( )
VOUT
VIN
VOUT
VIN
50Ω
MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS.
INSERTION LOSS IS MEASURED BETWEEN R0 AND R1 OR R2 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
5
MAX4885AE
Test Circuits/Timing Diagrams
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
MAX4885AE
Pin Configuration
B1
H1
V1
I.C.
V2
H2
B2
TOP VIEW
21
20
19
18
17
16
15
14
G1 22
G2
R1 23
13
R2
SCL1 24
12
SCL2
11
SDA2
10
VCC
9
VL
8
SEL2
MAX4885AE
SDA1 25
GND 26
VCC 27
*EP
+
4
5
6
7
V0
SDA0
SCL0
R0
3
B0
2
H0
1
G0
SEL1 28
TQFN
(4mm × 4mm)
*EXPOSED PAD. CONNECT TO GROUND OR LEAVE UNCONNECTED.
Pin Description
6
PIN
NAME
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
R0
G0
B0
H0
V0
SDA0
SCL0
SEL2
VL
VCC
SDA2
SCL2
R2
G2
B2
H2
V2
I.C.
V1
H1
B1
FUNCTION
RGB Red Output (Note 4)
RGB Green Output (Note 4)
RGB Blue Output (Note 4)
Horizontal Sync Output (Note 4)
Vertical Sync Output (Note 4)
I2C Data Output (Note 4)
I2C Clock Output (Note 4)
Select Input 2. Switches SDA_ and SCL_ signals.
Supply Voltage. +2.2V P VL P VCC. Bypass VL to GND with a 1FF or larger ceramic capacitor.
Supply Voltage. VCC = +5.0V Q10%. Bypass VCC to GND with a 1FF or larger ceramic capacitor.
I2C Input Data 2 (Note 5)
I2C Input Clock 2 (Note 5)
RGB Red Input 2 (Note 6)
RGB Green Input 2 (Note 6)
RGB-Blue Input 2 (Note 6)
Horizontal Sync Input 2 (Note 7)
Vertical Sync Input 2 (Note 7)
Internal Connection. Connect to ground or leave unconnected.
Vertical Sync Input 1 (Note 7)
Horizontal Sync Input 1 (Note 7)
RGB Blue Input 1 (Note 6)
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
PIN
NAME
22
23
24
25
26
27
28
—
G1
R1
SCL1
SDA1
GND
VCC
SEL1
EP
Note
Note
Note
Note
4:
5:
6:
7:
FUNCTION
RGB Green Input 1 (Note 6)
RGB Red Input 1 (Note 6)
I2C Clock Input 1 (Note 5)
I2C Data Input 1 (Note 5)
Ground
+5V Supply Pin
Select Input 1. Switches R_, G_, B_, H_, and V_ signals.
Exposed Pad. Connect exposed pad to ground or leave unconnected.
Terminal with Q15kV HBM protection.
SCL1, SCL2, SDA1, and SDA2 are identical and can be used interchangeably.
R1, R2, G1, G2, B1, and B2 are identical and can be used interchangeably.
H1, H2, V1, and V2 are identical and can be used interchangeably.
Typical Applications Circuit
+5.0V
+3.3V
0.1µF
3.3kΩ
0.1µF
3.3kΩ
24
25
20
19
SCL
SDA
H
MXM
V
GRAPHICS
R
G
B
9
23
22
21
10, 27
MAX4885AE
+3.3V
3.3kΩ
SCL
SDA
H
INTERNAL V
GRAPHICS
R
G
B
3.3kΩ
12
11
16
17
13
14
15
26, EP
28
8
SEL1
SEL2
7
SCL
6
SDA
4
H
5
V
1
R
2
G
3
B
VGA
COMMON
OUTPUT
NOTE: TWO VIDEO INPUT SOURCES BEING SWITCHED INTO ONE OUTPUT/SINK USING MAX4885AE.
7
MAX4885AE
Pin Description (continued)
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
MAX4885AE
Functional Diagram
R1
R0
R2
G1
G0
G2
B1
B0
B2
SCL1
SCL0
VL
SCL2
VL
SDA1
SDA0
VL
SDA2
VL
MAX4885AE
H1
H0
H2
V1
V0
V2
SEL1
SEL2
8
CONTROL
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
The MAX4885AE integrates high-bandwidth analog
switches and level-translating buffers to implement a
complete 2:1 multiplexer for VGA signals. The device
provides switching for RGB, HSYNC, VSYNC, SDA, and
SCL signals. These signals are required in notebook
VGA switching applications.
The HSYNC and VSYNC inputs feature level-shifting
buffers to support 5V-TTL output logic levels from lowvoltage graphics controllers. These buffered switches
can be driven from +2.0V up to +5.5V. RGB signals are
routed with high-performance analog switches. SDA_
and SCL_ are I2C signals with pullups to their respective
voltages. The MAX4885AE protects the low-voltage side
while effectively translating up to the high-voltage level.
Two select inputs are provided to individually select
groups of switches.
RGB, HSYNC, and VSYNC signals are controlled by
SEL1; and both SDA_ and SCL_ signals are controlled
by SEL2.
Table 1. RGB/HV Truth Table
SEL1
FUNCTION
0
R1 to R0
G1 to G0
B1 to B0
H1 to H0
V1 to V0
1
R2 to R0
G2 to G0
B2 to B0
H2 to H0
V2 to V0
FUNCTION
0
SDA1 to SDA0
SCL1 to SCL0
1
SDA2 to SDA0
SCL2 to SCL0
Horizontal/Vertical Sync Level Shifter
H1, H2, V1, and V2 inputs are buffered to provide levelshifting and drive capability for horizontal/vertical sync
signals that meet the VESA specification. The H_ and V_
level-shifters are identical, and each level-shifter can be
used for either horizontal or vertical signals. The SDA0
and SCL0 outputs are ESD protected to Q15kV (HBM).
Display-Data Channel Multiplexer
The MAX4885AE provides two logic-level translating
switches to route DDC signals (see Table 2). VL is normally set to +3.3V to provide logic-shifting for VESA
I2C-compatible signals. The MAX4885AE protects the
low-voltage graphics controller from +5V that could be
present in VESA-compatible monitors. In some applications, such as KVM, where logic-level shifting is not
required, then VL can be connected to VCC. The SDA_
and SCL_ switches are identical, and each switch can
be used to route either SDA_ or SCL_ signals. The SDA0
and SCL0 outputs are ESD protected to Q15kV (HBM).
ESD Protection
Table 2. DDC Truth Table
SEL2
RGB Switches
The MAX4885AE provides three SPDT high-bandwidth
switches to route standard VGA R_, G_, and B_ signals
(see Table 1). The R_, G_, and B_ analog switches are
identical and any of the three switches can be used to
route red, green, or blue video signals. The R0, G0, and
B0 outputs are ESD protected to Q15kV (HBM).
As with all Maxim devices, ESD-protection structures are
incorporated on all pins to protect against electrostatic
discharges encountered during handling and assembly.
Additionally, the R0, G0, B0, H0, V0, SDA0, and SCL0
terminals of the MAX4885AE are designed for protection
to the following limit: ±15kV using the HBM.
For optimum ESD performance, bypass VCC and VL pins
to ground with 1FF or larger ceramic capacitors as close
as possible to these supply pins.
9
MAX4885AE
Detailed Description
MAX4885AE
High-Bandwidth, VGA 2:1 Switch
with ±15kV ESD Protection
RC
1MΩ
CHARGE-CURRENTLIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
CS
100pF
RD
1.5kΩ
IP 100%
90%
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPERES
DEVICE
UNDER
TEST
Figure 4. Human Body ESD Test Model
Human Body Model
Figure 4 shows the HBM, and Figure 5 shows the current waveform it generates when discharged into a lowimpedance state. This model consists of a 100pF capacitor charged to the ESD voltage of interest, which is then
discharged into the device through a 1.5kI resistor.
36.8%
10%
0
0
TIME
tRL
tDL
CURRENT WAVEFORM
Figure 5. Human Body Model Current Waveform
Power-Supply Decoupling
Bypass each VCC pin and VL pin to ground with a 1FF
or larger ceramic capacitor as close as possible to the
device.
PCB Layout
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report, test setup, methodology, and results.
High-speed switches such as the MAX4885AE requires
proper PCB layout for optimum performance. Ensure that
impedance-controlled PCB traces for high-speed signals
are matched in length and as short as possible. Connect
the exposed pad to ground or leave unconnected.
Applications Information
Chip Information
ESD Test Conditions
The MAX4885AE provides the switching and levelshifting necessary to drive a standard VGA port from
either an internal graphics controller or an add-in module
(MXM or GPU—see Typical Applications Circuit). The
R_, G_, and B_ signals are switched through the three
low-capacitance SPDT switches. Internal buffers drive
the HSYNC and VSYNC signals to VGA standard 5V-TTL
levels. The DDC multiplexer provides level-shifting.
Connect VL to +3.3V for normal operation, or to VCC to
disable level-shifting for DDC signals as for KVM application.
PROCESS: BiCMOS
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that
a “+”, “#”, or “-” in the package code indicates RoHS
status only. Package drawings may show a different suffix character, but the drawing pertains to the package
regardless of RoHS status.
PACKAGE TYPE
PACKAGE CODE
DOCUMENT NO.
28 TQFN-EP
T2844+1
21-0139
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time.
10
© 2009
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.