Maxim MAX14895E Enhanced vga port protector ddc outputs have internal pullup Datasheet

19-5819; Rev 0; 3/11
EVALUATION KIT AVAILABLE
MAX14895E
Enhanced VGA Port Protector
General Description
Benefits and Features
The MAX14895E integrates level-translating buffers and
features RED, GRN, and BLU (RGB) port protection for
VGA signals.
S Saves Power in Portable Applications
 Low Quiescent Supply Current: 430µA (typ)
S Eliminates Need for Costly External Components
 High-ESD Protection on SDA1, SCL1, SYNCH1,
SYNCV1, RED, GRN, BLU, EN, VS
 ±15kV Human Body Model (HBM)
 ±8kV IEC 61000-4-2 Contact Discharge
The device has horizontal sync (SYNCH_) and vertical
sync (SYNCV_) translating buffers that convert low-level
CMOS inputs from a graphics controller to meet full 5V,
TTL-compatible outputs. Each output can drive Q10mA
and meets the VESASM specification. In addition, the
device translates the direct digital control (DDC) signals
to a lower level that is safe for the graphics controller.
S Innovative Design Enables a High Level of
Integration for Performance
 Output Current-Limit Switch with Power-Off
Protection
 Low Capacitance on RGB Ports (2.2pF typ)
 ±10mA Drive on SYNCH1, SYNCV1
The device features both EN and EN inputs, accepting
active-high or active-low enable inputs. The device also
switches and current limits the 5V supply to a VGA connector or monitor.
S Fully Integrated Solutions Saves Space in Portable
Applications
 DDC Outputs have Internal Pullups
 3mm x 3mm, 16-Pin TQFN Package
The RED, GRN, and BLU terminals protect graphics controller outputs against electrostatic discharge (ESD) events.
All eight outputs and EN have high-level ESD protection.
The MAX14895E is specified over the extended -40NC to
+85NC temperature range and is available in a 16-pin,
3mm x 3mm TQFN package with exposed pad.
Ordering Information appears at end of data sheet.
Applications
Notebook Computers
Servers
Desktops
Graphics Cards
For related parts and recommended products to use with this part,
refer to www.maxim-ic.com/MAX14895E.related.
Typical Operating Circuit
+5V
1µF
VCC
EN
VS
1µF
2
VGA
OUTPUTS
2
EN
SYNCH0, SYNCV0
SYNCH1, SYNCV1
SDA0, SCL0
SDA1, SCL1
RED
GRN
BLU
2
2
VGA
PORT
MAX14895E
GND
VESA is a service mark of the Video Electronics Standards Association Corporation.
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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.
MAX14895E
Enhanced VGA Port Protector
ABSOLUTE MAXIMUM RATINGS
(Voltages referenced to GND.)
VCC, VS, EN, SDA0, SCL0.......................................-0.3V to +6V
SDA1, SCL1................................................. -0.3V to (VS + 0.3V)
EN, RED, GRN, BLU, SYNCH0,
SYNCH1, SYNCV0, SYNCV1................. -0.3V to (VCC + 0.3V)
Continuous Current through SDA_, SCL_........................ Q30mA
Continuous Short-Circuit Current SYNCH1, SYNCV1...... Q20mA
Continuous Power Dissipation (TA = +70NC)
TQFN (derate 20.8mW/NC above +70NC)..................1667mW
Operating Temperature Range........................... -40NC to +85NC
Junction Temperature......................................................+150NC
Storage Temperature Range............................. -65NC to +150NC
Lead Temperature (soldering, 10s).................................+300NC
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 (BJA)...........48NC/W
Junction-to-Case Thermal Resistance (BJC)..................7NC/W
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 www.maxim-ic.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(VCC = +4.75V to +5.25V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = +5V, TA = +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
5.25
V
800
FA
8
FA
4.3
V
POWER SUPPLY
Power-Supply Range
VCC
4.75
Quiescent Supply Current
IQ
EN = VCC, EN = GND,
SYNCH0 = SYNCV0 = GND,
SDA0 = SCL0 = unconnected
Shutdown Supply Current
ISHDN
EN = GND, EN = VCC,
SYNCH0 = SYNCV0 = GND,
SDA0 = SCL0 = unconnected
Undervoltage Lockout Threshold
VUVLO
VCC rising
430
Undervoltage Lockout Hysteresis
Internal Logic Supply Voltage
0.1
VL
V
VCC = +4.75V to +5.25V, SDA1/SCL1 =
unconnected, measure SDA0/SCL0
1.6
2.9
VCC = +4.75V to +5.25V, SDA0/SCL0 =
200kI to GND, measure SDA0/SCL0,
SDA1/SCL1 = unconnected
1.6
2.8
V
RED, GRN, BLU
RED, GRN, BLU Capacitance
COUT
RED, GRN, BLU Leakage Current
f = 1MHz, VRED, GRN, BLU = 1VP-P
2.2
-1
pF
+1
FA
SYNCH0, SYNCV0, EN, EN
Input Logic-High
VIH
Input Logic-Low
VIL
2.0
V
0.8
V
����������������������������������������������������������������� Maxim Integrated Products 2
*The parametric values (min, typ, max limits) shown in the Electrical Characteristics table supersede values quoted elsewhere in this data sheet.
MAX14895E
Enhanced VGA Port Protector
ELECTRICAL CHARACTERISTICS* (continued)
(VCC = +4.75V to +5.25V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = +5V, TA = +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
MAX
UNITS
-1
+1
FA
800
kI
SYNCH0, SYNCV0 Leakage
Current
SYNCH0/SYNCV0 = GND or VCC
EN, EN Input Resistance
EN = VCC, EN = GND
200
2.4
TYP
SYNCH1, SYNCV1
Output Logic-High
VOH
VCC = +4.75V, source 10mA
Output Logic-Low
VOL
VCC = +4.75V, sink 10mA
V
0.5
V
Rising Time
tR
RL = 2.2kI, CL = 10pF, 10% to 90% of VCC
(Note 3)
4
ns
Falling Time
tF
RL = 2.2kI, CL = 10pF, 90% to 10% of VCC
(Note 3)
4
ns
Propagation Delay
tPD
RL = 2.2kI, CL = 10pF, EN = VCC, EN =
GND (Figure 1)
16
ns
Enable Time
tEN
RL = 2.2kI, CL = 10pF, VSYNCH1, VSYNCV1
= +4.75V (Figure 1)
17
Fs
RON
VSDA0 = VSCL0 = 0.5V, ILOAD = 10mA
SDA_, SCL_ (DDC)
On-Resistance
55
I
SDA0, SCL0 Off-Leakage Current
EN = GND, EN = VCC,
SDA0 = SCL0 = VCC, SDA1 = SCL1 = GND
-1
+1
FA
SDA1, SCL1 Reverse-Leakage
Current
VCC = 0V, VS = +5.25V,
VSDA1 = VSCL1 = +5.25V
-10
+10
FA
VCC = +4.75V, SDA0 = SCL0 =
unconnected, EN = VCC , EN = GND,
ILOAD = 100FA
1.25
4.0
kI
SDA1, SCL1 Pullup Resistor
RPULLUP
2.5
VS OUTPUT
Forward Voltage Drop
ILOAD = 60mA, VCC = 5V
Reverse-Leakage Current
VCC = 0V, VS = 5.25V
Current Limit
ILIM
Discharge Resistor
RVS
200
ILOAD = 1mA
300
0.25
V
10
FA
600
mA
500
I
THERMAL SHUTDOWN
Thermal Shutdown Threshold
+150
NC
Thermal Shutdown Hysteresis
10
NC
HBM
±15
kV
IEC 61000-4-2 Contact
±8
kV
ESD PROTECTION
SDA1, SCL1, SYNCH1, SYNCV1,
RED, GRN, BLU, EN, VS
Note 2: All devices are 100% production tested at TA = +25NC. Limits over the operating temperature range are guaranteed by
design and not production tested.
Note 3: Guaranteed by design.
����������������������������������������������������������������� Maxim Integrated Products 3
*The parametric values (min, typ, max limits) shown in the Electrical Characteristics table supersede values quoted elsewhere in this data sheet.
MAX14895E
Enhanced VGA Port Protector
2.4V
VSYNCH0/VSYNCV0
50%
50%
0V
OUTPUT HIGH
VSYNCH1/VSYNCV1
50%
50%
OUTPUT LOW
tPHL
tPLH
tPD = MAX(tPLH, tPHL)
2.4V
VEN
50%
0V
2.4V
VEN
50%
0V
OUTPUT HIGH
VSYNCH1/VSYNCV1
50%
OUTPUT LOW
tEN
Figure 1. Timing Diagram
����������������������������������������������������������������� Maxim Integrated Products 4
MAX14895E
Enhanced VGA Port Protector
Typical Operating Characteristics
(VCC = +5V, TA = +25NC, unless otherwise noted.)
SDA0, SCL0 ARE
INTERCHANGEABLE
70
5.8
50
40
TA = +25°C
30
TA = +85°C
20
5.2
5.0
4.8
4.6
4.2
TA = -40°C
4.0
0
0.5
5.4
4.4
10
0
IOUT = 8mA
5.6
OUTPUT VOLTAGE (V)
60
1.0
1.5
2.0
2.5
-40
3.0
-15
10
35
60
85
TEMPERATURE (°C)
VSDA0 (V)
1.0
0.9
MAX14895E toc03
HV BUFFER OUTPUT-VOLTAGE LOW
vs. TEMPERATURE
IOUT = 8mA
0.8
OUTPUT VOLTAGE (V)
RON (Ω)
6.0
MAX14895E toc01
80
MAX14895E toc02
HV BUFFER OUTPUT-VOLTAGE HIGH
vs. TEMPERATURE
ON-RESISTANCE vs. SDA0 VOLTAGE
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-40
-15
10
35
60
85
TEMPERATURE (°C)
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MAX14895E
Enhanced VGA Port Protector
SYNCH0
SCL1
SCL0
TOP VIEW
SYNCH1
Pin Configuration
12
11
10
9
SYNCV0 13
SYNCV1 14
MAX14895E
VCC 15
*EP
3
4
GND
1
RED
2
BLU
+
GRN
EN 16
8
SDA1
7
SDA0
6
EN
5
VS
TQFN
(3mm x 3mm)
*CONNECT EP TO GND.
Pin Description
PIN
NAME
1
RED
High-ESD Protection Diodes for RGB Signals
FUNCTION
2
GRN
High-ESD Protection Diodes for RGB Signals
3
BLU
High-ESD Protection Diodes for RGB Signals
4
GND
Ground
5
VS
Supply Voltage Output with Current-Limit Switch. VS provides a current-limited voltage from VCC when the
device is enabled. Bypass VS to GND with a 1FF or larger ceramic capacitor as close as possible to the device.
6
EN
Active-Low Enable Input. Drive EN high and EN low to disable the device. EN is weakly pulled up internally.
7
SDA0
DDC Data Input from Graphics Controller
8
SDA1
DDC Data Output to VGA Monitor. Internally pulled up to VCC.
9
SCL0
DDC Clock Input from Graphics Controller
10
SCL1
11
SYNCH0
DDC Clock Output to VGA Monitor. Internally pulled up to VCC.
Horizontal Sync Input
12
SYNCH1
Horizontal Sync Output
13
SYNCV0
Vertical Sync Input
14
SYNCV1
Vertical Sync Output
15
VCC
Supply Voltage Input. Apply a voltage between +4.75V and +5.25V to VCC to power the device. Bypass VCC
to GND with a 1FF or larger ceramic capacitor as close as possible to the device.
16
EN
Active-High Enable Input. Drive EN low and EN high to disable the device. EN is weakly pulled down internally.
—
EP
Exposed Pad. Connect EP to GND. For enhanced thermal dissipation, connect EP to a large ground plane.
Do not use EP as the only ground connection.
����������������������������������������������������������������� Maxim Integrated Products 6
MAX14895E
Enhanced VGA Port Protector
Functional Diagram/Truth Table
VCC
THERMAL
SHUTDOWN
EN
MAX14895E
CURRENT-LIMIT
SWITCH
LOGIC
EN
VS
SDA/SCL PULLUP
RESISTOR
SWITCHES
HIGH ESD
RPULLUP
RVS
HIGH ESD
VS PULLUP-TO-GND
SWITCHES
RPULLUP
SDA0
SDA1
HIGH ESD
I2C LEVEL SHIFTER
SCL1
SCL0
HIGH ESD
SYNCH0
SYNCH1
HIGH ESD
SYNCV0
SYNCV1
HIGH ESD
RED
GRN
HIGH ESD
BLU
HIGH ESD
HIGH ESD
GND
EN
EN
0
0
DEVICE LOGIC
Enable
0
1
Disable
1
0
Enable
1
1
Enable
DEVICE LOGIC/
EVENT
SYNCH_/SYNCV_
BUFFER
I2C LEVEL
SHIFTER
CURRENT-LIMIT
SWITCH
SDA/SCL PULLUP
RESISTOR SWITCHES
VS PULL-TO-GND
SWITCH
Enable
No Overcurrent
On
On
On
On
Off
Enable
Overcurrent
On
On
Current Limit
On
Off
Enable
Overcurrent
Thermal Shutdown
Output 0V
Off
Off
Off
On
Disable
Output 0V
Off
Off
Off
On
VCC = 0V
Off
Off
Off
Off
Off
����������������������������������������������������������������� Maxim Integrated Products 7
MAX14895E
Enhanced VGA Port Protector
Detailed Description
The MAX14895E integrates level-translating buffers and
features RED, GRN, and BLU port protection for VGA signals. Horizontal and vertical synchronization (SYNCH0,
SYNCV0) inputs feature level-shifting buffers to support
low-voltage CMOS or standard TTL-compatible graphics
controllers. Each output can drive Q10mA and meets
VESA specifications. The device also features I2C level
shifting using two nMOS devices.
The device generates its own internal bias supply to
clamp SCL0 and SDA0 to a safe level, removing the need
for another external supply. The device also provides a
current-limited VCC output with power-off protection. This
output can be used to switch power to a VGA connector
or the VGA interface of a monitor.
Horizontal/Vertical Sync Level Shifter
SYNCH0 and SYNCV0 are buffered to provide level shifting and drive capability to meet the VESA specification.
The level-shifted outputs (SYNCH1, SYNCV1) are pulled
low when EN is low and EN is high, or when the device
is in thermal shutdown (see the Functional Diagram/
Truth Table). Logic-level outputs (VOL, VOH) are 5V TTLcompatible. These two buffers are identical and each
can drive either the horizontal or the vertical synch signal.
Display Data Channel Switches
The device incorporates two nMOS switches for I2C
level shifting. The SDA0 and SCL0 terminals are voltage
clamped to a diode drop less than the internal VL voltage. Voltage clamping provides protection and compatibility with the SDA0 and SCL0 signals and low-voltage
ASICs. When power is off (VCC = 0V), SDA1 and SCL1
are protected against reverse-leakage current up to VS =
+5.25V. The SDA_ and SCL_ switches are identical, and
each switch can be used to route SDA_ or SCL_ signals.
RGB Ports
The device includes three terminals for RED, GRN, and
BLU signals. These terminals provide high-level ESD protection to the RGB lines while keeping the capacitance
on the RGB lines to a minimum. The RED, GRN, BLU
terminals are identical, and any of the three terminals
can be used to protect red, green, or blue video signals.
EN, EN
The device has dual complementary EN and EN enable
inputs and can accept either active-low or active-high
enable signals. Pull EN low and EN high to place the device
in shutdown (see the Functional Diagram/Truth Table).
VS Output
The device provides a current-limited voltage on VS when
the part is enabled. VS is used as the pullup voltage for
internal pullup resistors on SDA1 and SCL1, and can be
used as an external supply. The internal pullup resistors
from SDA1 and SCL1 to VS are active when the device is
enabled, and are disabled when the device is in thermal
shutdown (see the Functional Diagram/Truth Table).
The VS supply includes an internal resistor to discharge
the supply when the device is in thermal shutdown or is
disabled (see the Functional Diagram/Truth Table). VS is
current limited to prevent damage to host devices. When
power is off (VCC = 0V), VS is protected against reverseleakage current up to VS = +5.25V.
Thermal Shutdown
Thermal-shutdown circuitry protects the device from
overheating. The device enters thermal shutdown when
the junction temperature exceeds +150NC (typ) and
returns to normal operation when the temperature drops
by approximately +10NC (typ) below the thermal-shutdown threshold. When the device is in thermal shutdown,
both SYNCH1 and SYNCV1 are pulled down to ground,
the I2C level shifters are disabled, the SDA1 and SCL1
pullups are off, and the VS discharge resistor is on (see
the Functional Diagram/Truth Table).
Applications Information
Power-Supply Decoupling
Bypass VCC and VS to ground with 1FF ceramic capacitors as close as possible to the device.
PCB Layout
High-speed switches such as the MAX14895E require
proper PCB layout for optimum performance. Ensure that
impedance-controlled PCB traces for high-speed signals
are matched in length and are as short as possible.
Connect the exposed pad to a solid ground plane.
ESD Protection
As with all Maxim devices, ESD protection structures
are incorporated on all terminals to protect against electrostatic discharges encountered during handling and
assembly. Additionally, the device is protected to Q15kV
on the RED, GRN, BLU, EN, VS, SYNCH1, SYNCV1,
SCL1, and SDA1 terminals by the HBM. For optimum
ESD performance, bypass VCC to ground with a 1FF
ceramic capacitor.
����������������������������������������������������������������� Maxim Integrated Products 8
MAX14895E
Enhanced VGA Port Protector
ESD protection can be tested in various ways. The RED,
GRN, BLU, EN, VS, SYNCH1, SYNCV1, SCL1, and SDA1
terminals of the device are characterized for protection to
the following limits:
• Q15kV using the HBM
• Q8kV using IEC 61000-4-2 Contact Discharge
Human Body Model
Figure 2 shows the HBM. Figure 3 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 that is then
discharged into the device through a 1.5kI resistor.
IEC 61000-4-2
The IEC 6100-4-2 standard covers ESD testing and performance of finished equipment. However, it does not
specifically refer to integrated circuits. The device assists
in designing equipment to meet IEC 61000-4-2 without
the need for additional ESD protection components.
The major difference between tests done using the HBM
and IEC 61000-4-2 is higher peak current in IEC 610004-2 because series resistance is lower in the IEC 610004-2 model. Hence, the ESD withstand voltage measured
to IEC 61000-4-2 is generally lower than that measured
using the HBM. Figure 4 shows the IEC 61000-4-2 model,
and Figure 5 shows the current waveform for the IEC
61000-4-2 ESD Contact Discharge test.
RC
1MΩ
RD
1.5kΩ
RC
50MΩ TO 100MΩ
RD
330Ω
CHARGE-CURRENTLIMIT RESISTOR
DISCHARGE
RESISTANCE
CHARGE-CURRENTLIMIT RESISTOR
DISCHARGE
RESISTANCE
HIGHVOLTAGE
DC
SOURCE
CS
100pF
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
Figure 2. Human Body ESD Test Model
CS
150pF
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
Figure 4. IEC 61000-4-2 ESD Test Model
IPEAK (AMPS)
IPEAK (AMPS)
Ir
100%
90%
HIGHVOLTAGE
DC
SOURCE
100%
90%
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
36.8%
10%
0
0
TIME
tRL
tDL
10%
t
tR = 0.7ns TO 1ns
30ns
60ns
Figure 3. Human Body Current Waveform
Figure 5. IEC 61000-4-2 ESD Generator Current Waveform
����������������������������������������������������������������� Maxim Integrated Products 9
MAX14895E
Enhanced VGA Port Protector
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX14895EETE+T
-40NC to +85NC
16 TQFN-EP*
+Denotes lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
*EP = Exposed pad.
Chip Information
Package Information
For the latest package outline information and land patterns
(footprints), 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
OUTLINE
NO.
LAND
PATTERN NO.
16 TQFN-EP
T1633+4
21-0136
90-0031
PROCESS: BiCMOS
���������������������������������������������������������������� Maxim Integrated Products 10
MAX14895E
Enhanced VGA Port Protector
Revision History
REVISION
NUMBER
REVISION
DATE
0
3/11
DESCRIPTION
Initial release
PAGES
CHANGED
—
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
©
2011 Maxim Integrated Products
11
Maxim is a registered trademark of Maxim Integrated Products, Inc.
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