MAXIM MAX14984 Technical data

EVALUATION KIT AVAILABLE

19-6229; Rev 0; 3/12

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

General Description

The MAX14984 is a complete VGA port protector with dual USB power switches. The device features all the circuitry required to detect the insertion and removal of a monitor and automatically connect the graphics controller when a monitor is detected. A switched 5V output provides up to 55mA to the VGA port in addition to normal VGA signals.

The MAX14984 features a single active-low enable input to control two 5V USB switches. Each switch supplies 500mA of current with less than 250mV drop from VCC, and is protected against short-circuit faults. Two active-low fault outputs indicate when a fault condition is detected on either output.

High-bandwidth analog switches exceed VESA rise/ fall time requirements for the RGB channels. The horizontal and vertical synchronization (H/V) buffers shift logic levels to support +2.5V to +5.0V CMOS or TTL-compatible graphics controllers while meeting the VESA drive capability requirement of Q8mA. An internal 2.5V regulator and pullup resistors on the monitor side translate the DDC voltage levels to be compatible with low-voltage graphics controllers.

The MAX14984 features high-ESD protection of Q8kV Human Body Model (HBM) on all VGA and USB outputs. The device is available in a 24-pin (4mm x 4mm) TQFN package and is specified over the -40NC to +85NC extended temperature range.

Applications

Servers Workstations Desktop PCs

Ordering Information appears at end of data sheet.

For related parts and recommended products to use with this part, refer to www.maxim-ic.com/MAX14984.related.

Benefits and Features

S Design Flexibility

 Graphics Controller Port Is Protected when VCC = 0V  External Pullup Resistors Match DDC Channel to Graphics Controller Supply  Up to Two USB Ports Supported

S High Level of Integration for Performance

 S5V Provides +5V at 55mA to VGA Port 

Internal Pullup Resistors on DDC Outputs to S5V

 Low 6pF (typ) RGB Capacitance  2.1ns (typ) tR/tF with 10pF, 2.2kI Load on

Monitor-Side SYNC Signals  Source and Sink 8mA While Meeting Speed Requirements  High-ESD Protection on VGA and USB Outputs Q8kV Human Body Model (HBM)

S Saves Space on Board

 Internal USB Switches Pass +5V at 500mA with 250mV (max) IR Drop Current Limited/Thermal Protection  4mm x 4mm, 24-Pin TQFN Package

Typical Operating Circuit

+3.3V +5V

1µF

3

2

S5V

1µF

USB1

1µF

USB2

1µF

GRAPHICS

CONTROLLER

+3.3V

3

2

R0, G0, B0

HSYNC0, VSYNC0

SCL0, SDA0

F1, F2

ENU

MAX14984

MD

ENV

V

GND

CC

R1, G1, B1

HSYNC1,

VSYNC1

SCL1, SDA1

VGA

PORT

USB

DEVICE

USB

DEVICE

�� 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.

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

ABSOLUTE MAXIMUM RATINGS

(All voltages referenced to GND.) VCC, S5V, H0, V0, SDA0, SCL0, ENU, ENV, SDA1,

SCL1, USB1, USB2, MD, F1, F2 (Note 1) ...........-0.3V to +6V

R0, G0, B0, R1, G1, B1, H1, V1 .................. -0.3V to VCC + 0.3V

Continuous Current Out of USB1, USB2 ..........................500mA

Continuous Current Out of S5V ..........................................60mA

Continuous Current Through all I/O Pins ........................ Q50mA

Peak Current Through RGB, DDC Switches

(1ms Pulse, 10% Duty Cycle) .................................... Q100mA

PACKAGE THERMAL CHARACTERISTICS (Note 2)

TQFN

Junction-to-Ambient Thermal Resistance (qJA) ..........36°C/W Junction-to-Case Resistance (qJA) ...................................3°C/W

Note 1: When F1 and F2 are connected to a voltage higher than VCC, some current will be sinked (see the Detailed Description). Note 2: 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.

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 = 5.0V Q 5%, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = 5.0V and TA = +25NC.) (Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNIT

POWER SUPPLY

Supply Voltage V

Supply Current I

Shutdown Supply Current I

5-VOLT SWITCH (S5V)

Voltage Drop V

Reverse Leakage Current I

Current Limit I

USB SWITCHES (USB1, USB2)

Voltage Drop V

Continuous Load Current I

Current-Limit Threshold I

Current-Limit Blanking Period

Output Rise Time t

Output Fall Time t

Turn-On Delay t

Turn-Off Delay t

Reverse Leakage Current I Pulldown Resistance 1200

CC

SHDN

S5V

L

LIM

USB

LOAD

LIM

t

BLANK

R

F

ON

OFF

LUSB

VCC = +5.25V, V SDA0 not connected

VCC = +5.25V, V V

= V

SCL0

VCC = +5.25V, V

I

= 55mA 135 300 mV

OUT

V

= +5.25V, VCC = 0V, V

S5V

I

= 500mA 250 mV

OUT

(Note 4) 7.5 50 ms

RL = 10I, CL = 1FF, 10%–90%, Figure 1

RL = 10I, CL = 1FF, 90%–10%, Figure 1

RL = 10I, CL = 1FF, to 10% of V

RL = 10I, CL = 1FF, to 90% of V

V

= 5.25V, VCC = 0V, V

USB

SDA0

= 0V

Continuous Power Dissipation (TA = +70C)

TQFN (derate 27.8mW/NC above +70C) ................2222.2mW

Operating Temperature Range .......................... -40NC to +85NC

Junction Temperature .....................................................+150NC

Storage Temperature Range ............................ -65NC to +150NC

Lead Temperature (soldering, 10s) ................................+300NC

Soldering Temperature (reflow) ......................................+260NC

4.75 5.25 V

ENV

= V

= 0V, SCL0 and

ENU

= 0V,

ENU

= V

ENU

ENV

ENU

CC

= 0V

OUT

= 0V

, Figure 1

2.3 5

6.6 10

29 100

55 305 500 mA

500 mA

0.5 1.0 A

11.6

25.2

100

10

mA

FA

Fs

FA

I

�� Maxim Integrated Products 2

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

ELECTRICAL CHARACTERISTICS (continued)

(VCC = 5.0V Q 5%, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = 5.0V and TA = +25NC.) (Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNIT

DDC SWITCHES (SDA0, SCL0, SDA1, SCL1)

SDA1/SCL1 Off-Leakage Current

SDA0/SCL0 Off-Leakage Current

On-Resistance R

LOGIC INPUTS (H0, V0, ENV, ENU)

Input Logic-Low V

Input Logic-High V

Input Leakage Current I

Input Hysteresis (H0, V0) V

PUSH-PULL LOGIC OUTPUTS (H1, V1)

Output Logic-Low V

Output Logic-High V

Rise/Fall Time tR, t

OPEN-DRAIN LOGIC OUTPUTS (F1, F2, MD)

Output Leakage Current I

Output Logic-Low V

RGB ANALOG SWITCHES (R0, G0, B0, R1, G1, B1)

Bandwidth f

On-Loss I

On-Resistance R

On-Resistance Matching

On-Resistance Flatness R

On-Capacitance C

Off-Capacitance C

PROTECTION SPECIFICATIONS

High-ESD Pins ESD Protection

All Other Pins ESD Protection

Thermal-Shutdown Threshold

Thermal-Shutdown Hysteresis

Note 3: All units are production tested at TA = +25NC. Specifications over temperature are guaranteed by design. Note 4: t Note 5: See the Pin Description section for the ESD status of each pin. Note 6: Terminal tested vs. GND. Apply 1FF-bypass capacitors on VCC, USB1, USB2, and S5V.

is the period between detecting an overcurrent condition and the fault output asserting.

BLANK

�� Maxim Integrated Products 3

I

OFF

I

LDDC

ONDDC

IL

IH

L

HYST

OL

OH

F

LKG

OL

MAX

LOSS

ON

DR

ON

FLAT(ON)

ON

OFF

T

SHDN

T

SHDN_

HYS

V

= VCC, V

ENV

VCC = 0V, 3.3kI pullup to +3.3V on SDA0 and SCL0

VIN = +0.8V, IIN = Q10mA

VIN = 0V or 5.25V -1 +1

I

= 8mA, VCC = +4.75V 0.5 V

SINK

I

SOURCE

10% to 90%, RL = 2.2kI, CL = 10pF

Output not asserted, VIN = 5.25V 1

I

SINK

RS = RL = 50I

f = 50MHz, RS = RL = 50I, 0V P VIN P +0.7V,

Figure 2

VIN = +0.7V, IIN = Q10mA

0V P VIN P +0.7V, IIN = Q10mA, same device

0V P VIN P +0.7V, IIN = Q10mA

f = 1MHz, switches enabled 6 pF

f = 1MHz, switches disabled 2 pF

Human Body Model (Note 5)

Human Body Model (Note 6)

= 8mA, VCC = +4.75V 2.4 V

= 1mA 0.3 V

SDA1

= V

= 0V or 5.25V

SCL1

-1 +1

10

7

0.8 V

2.0 V

100 mV

2.1 ns

1000 MHz

0.4 dB

5 8

1

0.25 1

Q8

Q2

+155

25

FA

I

FA

I

kV

NC

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Test Circuits/Timing Diagrams

3.3V

V

ENU

0V

t

OFF

t

F

t

ON

R

5V

V

USB1,

V

USB2

0V

Figure 1. Timing Diagram for USB Switch Parameters

+5V

1µF

V

0V

ENV

CC

R0, G0, B0

MAX14984

R1, G1, B1

GND

90% 90%

10% 10%

NETWORK ANALYZER

V

IN

V

OUT

50I

MEAS REF

50I 50I

50I

ON-LOSS = 20log

V

OUT

V

IN

MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS. ON-LOSS IS MEASURED BETWEEN R0 AND R1 ON EACH SWITCH. SIGNAL DIRECTION THROUGH IS REVERSED; WORST VALUES ARE RECORDED.

Figure 2. On-Loss

�� Maxim Integrated Products 4

Enhanced VGA Port Protector with Monitor

05

11

02

Detection and Dual USB Power Switches

(VCC = +5.0V, TA = +25NC, unless otherwise noted)

MAX14984

Typical Operating Characteristics

DDC ON-RESISTANCE

vs. ANALOG SIGNAL VOLTAGE

50

I

= 10mA

SDA0

40

30

(I)

ON

R

20

TA = +85°C

10

0

FREQUENCY RESPONSE

0

-1

-2

-3

-4

-5

-6

-7

FREQUENCY RESPONSE (dB)

-8

-9

GO TO G1

-10

FREQUENCY (MHz)

TA = +25°C

V

SDA0

(V)

TA = -40°C

1.51.00.5

10010

MAX14984 toc01

.0

MAX14984 toc03

k

RGB ON-RESISTANCE

vs. ANALOG SIGNAL VOLTAGE

50

IR0 = 10mA

40

30

(I)

ON

R

20

TA = +85°C

10

0

TA = +25°C

VR0 (V)

HSYNC/VSYNC OUTPUT VOLTAGE

vs. TEMPERATURE

5

I

SOURCE/ISINK

4

3

(V)

OL

/V

OH

V

2

1

0

-40 85

= 8mA

V

OL

TA (°C)

V

TA = -40°C

OH

603510-15

MAX14984 toc02

4321

MAX14984 toc04

�� Maxim Integrated Products 5

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Pin Configuration

TOP VIEW

SDA1

SCL1

V

SDA0

SCL0

G1

1718 16 14 13

19

20

21

CC

22

CC

23

+

24

12

R0

G0

B1

15

MAX14984

*EP/GND

456

3

B0

H1

H0

V1R1S5V

V0

MD

12

ENU

ENV

11

USB2

10

9

USB1

F2

8

F1

7

TQFN

(4mm x 4mm)

*CONNECT THE EXPOSED PAD (EP/GND) TO THE GROUND PLANE.

Pin Description

PIN NAME FUNCTION ESD

1 R0 RGB Analog Input Standard 2 G0 RGB Analog Input Standard 3 B0 RGB Analog Input Standard 4 H0 Horizontal Sync Input Standard 5 V0 Vertical Sync Input Standard 6

7

8

MD Monitor Detect Output. MD is an active-low, open-drain output.

F1

F2

Fault Output 1. F1 is an active-low, open-drain output that asserts when a fault condition is detected on USB1.

Fault Output 2. F2 is an active-low, open-drain output that asserts when a fault condition is detected on USB2.

9 USB1 5V USB Power Output 1. USB1 is internally pulled down when not enabled. High 10 USB2 5V USB Power Output 2. USB2 is internally pulled down when not enabled. High 11 12

ENV Video Enable Input. Drive ENV low to connect the VGA signals to the VGA port. ENU USB Enable Input. Drive ENU low to enable the USB power-supply outputs.

Standard

High High

�� Maxim Integrated Products 6

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Pin Description (continued)

PIN NAME FUNCTION ESD

13 S5V

14 V1 Vertical Sync Output High 15 H1 Horizontal Sync Output High 16 B1 RGB Analog Output High 17 G1 RGB Analog Output High 18 R1 RGB Analog Output High 19 SDA1 20 SCL1

21, 22 V

23 SDA0 DDC Input/Output Standard 24 SCL0 DDC Input/Output Standard

— EP/GND

CC

Switched 5V Output. S5V is connected when ENV is low and is internally pulled down when not connected.

DDC Input/Output. SDA1 has an internal 2.5kI pullup resistor to S5V DDC Input/Output. SCL1 has an internal 2.5kI pullup resistor to S5V

Supply Voltage. VCC = 5.0V Q5%. Bypass VCC to GND with a 1FF or larger ceramic capacitor as close as possible to VCC.

Exposed Pad. The exposed pad is the ground connection for the device. Connect EP/GND to the ground plane.

High

High High

Standard

—

�� Maxim Integrated Products 7

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Functional Diagram

V

CC

S5V

SDA0

SCL0

INTERNAL V

2.5V

REGULATOR

R0

G0

B0

H0

V0

F2

L

200I

MAX14984

R1

G1

B1

S5V

2.5kI

SDA1

2.5kI

SCL1

H1

V1

V

CC

USB1

F1

MD

ENU

ENV

MONITOR

DETECTION

THERMAL

PROTECTION

CONTROL

LOGIC

GND

1kI

USB2

1kI

�� Maxim Integrated Products 8

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Detailed Description

The MAX14984 integrates high-bandwidth analog switches and level-translating buffers with current-limited power switches to implement a VGA port protector. The device provides switching for red-green-blue (RGB) signals, horizontal and vertical synchronization (H/V) pulses, display data channel (DDC) signals, and 5V power supplies. The power switches provide +5V power with current limiting and reverse voltage protection to the VGA port and up to two USB ports.

The device uses a simplified power-supply interface that operates from a single +5V supply. An internal 2.5V regulator limits the voltage passed by the DDC switches to provide compatibility with low-voltage graphics controllers.

The device features two enable inputs, a monitor detection output, and two fault outputs. ENV can be connected to MD to automatically connect the graphics signal when a monitor is inserted. The fault outputs signal when a fault condition is detected on either of the USB power outputs and they are enabled by ENU.

5V Power Switch (S5V)

The MAX14984 provides a switched +5V output in addition to the regular VGA signals (S5V). This output can supply 55mA with less than 300mV drop from VCC. The S5V output tolerates +5V while turned off or when VCC is not present.

The power switches are protected against overcurrent and overtemperature faults. The device limits current supplied to the monitor side to 300mA (typ). Thermal protection circuitry shuts off the switch when the temperature exceeds +155NC. The device is re-enabled once the temperature has fallen to below +130NC.

S5V is connected whenever ENV is low and has a 200I (typ) pulldown resistor to discharge filter capacitors when the switch is off.

USB Switches and F1/F2 Outputs

The MAX14984 features two switches that provide power for up to two USB connectors. One enable input, ENU, controls both switches simultaneously. Each switch can provide up to 500mA while only dropping 250mV from VCC.

Two active-low fault outputs, F1 and F2, assert when a fault is detected on USB1 or USB2, respectively. Two fault conditions can be detected: short circuit to GND and overcurrent draw from the USB port. The switches are protected against reverse current into VCC while ENU is high, but this condition is not detected by F1 and F2. Current-limiting and thermal-shutdown circuitry protects the device in the presence of any fault.

A blanking period is built in to F1 and F2 that delays assertion until the current limit has been reached for at least t tor is connected on each USB output when it is disabled.

The F1 and F2 outputs are tolerant to external voltages of up to 6V. The MAX14984 limits the current into them to 600FA.

. In addition, an internal 1kI pulldown resis-

BLANK

RGB Switches

The MAX14984 provides three single-pole/single-throw (SPST) high-bandwidth switches to connect the standard VGA R, G, and B signals from the graphics controller to the VGA port. The R, G, B analog switches are identical, and any of the three switches can be used to route red, green, or blue video signals.

The RGB switches are connected when ENV is low.

Horizontal/Vertical Sync Buffer

The H/V signals are buffered to provide level shifting and drive capability to meet the VESA specification.

H1 and V1 are enabled when ENV is low and high impedance when ENV is high. The H and V channels are not interchangeable.

Display Data Channel Switches

(SDA_, SCL_)

The MAX14984 provides two voltage-limited SPST switches to connect DDC signals (SDA_, SCL_). These switches limit the voltage that can be passed through to the graphics controller to less than 2.5V. Internal pullup resistors on the monitor side of the switches translate the graphics controller signals to 5V compatible logic. Connect pullup resistors on SCL0 and SDA0 to define the logic level of the graphics controller.

The SDA_ and SCL_ switches are connected when ENV is low and are identical; either switch can be used to route SDA or SCL I2C signals.

�� Maxim Integrated Products 9

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Monitor Detection and

Automatic Switching

The MAX14984 detects monitor insertion/removal events by measuring the voltage on B1. The monitor detection circuitry always correctly indicates the presence of a monitor as long as V0 is not high impedance. The voltage measurement is only sampled between synchronization pulses on V0 from the controller when a monitor is inserted to ensure that the video signal is not interrupted while promptly detecting a removal.

The device automatically connects the graphics controller to the monitor when it is plugged in if configured in automatic mode. To configure automatic mode, connect MD to ENV and add a pullup resistor.

Applications Information

Compatibility with Low-Voltage

Graphics Controllers

The MAX14984 provides the level shifting necessary to drive a standard VGA port using any graphics controller. Internal buffers drive the H and V signals to VGA standard TTL levels. The DDC switches provide level shifting by limiting signal levels that can be passed through the DDC switches to less than 2.5V. Add pullup resistors from the DDC lines to the graphics controller supply to set the logic level on the SDA0/SCL0 side.

Power-Supply Decoupling

Bypass VCC to ground with a 1FF or larger ceramic capacitor as close to the device as possible.

PC Board Layout

High-speed switches such as the MAX14984 require 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 a solid ground plane.

High ESD Protection

Electrostatic Discharge (ESD) protection structures are incorporated on all pins to protect against electrostatic discharges up to Q2kV Human Body Model (HBM) encountered during handling and assembly. All VGA and USB outputs are further protected against ESD up to Q8kV (HBM) without damage (see the Pin Description). The ESD structures withstand high ESD both in normal operation and when the device is powered down. After an ESD event, the MAX14984 continues to function without latchup.

ESD Test Conditions

ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test setup, test methodology, and test results.

Human Body Model

Figure 3 shows the Human Body Model. Figure 4 shows the current waveform it generates when discharged into a low impedance. 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.

I

(AMPS)

R

C

1MΩ

CHARGE-CURRENT-

LIMIT RESISTOR

HIGH-

VOLTAGE

DC

SOURCE

Figure 3. Human Body ESD Test Model Figure 4. Human Body Current Waveform

C

S

100pF

�� Maxim Integrated Products 10

R

D

1.5kΩ

DISCHARGE

RESISTANCE

STORAGE CAPACITOR

DEVICE UNDER

TEST

PEAK

100%

90%

36.8%

10%

PEAK-TO-PEAK RINGING

I

r

(NOT DRAWN TO SCALE)

0

t

RL

t

DL

TIME

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Ordering Information

PART TEMP RANGE PIN-PACKAGE

MAX14984ETG+

+Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed paddle.

-40NC to +85NC

24 TQFN-EP*

Chip Information

PROCESS: BiCMOS

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

24 TQFN-EP T2444+3

PACKAGE

CODE

OUTLINE

NO.

21-0139 90-0021

LAND

PATTERN NO.

�� Maxim Integrated Products 11

MAX14984

Enhanced VGA Port Protector with Monitor

Detection and Dual USB Power Switches

Revision History

REVISION

NUMBER

0 3/12 Initial release —

REVISION

DATE

DESCRIPTION

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. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 12

©

2012 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.

MAXIM MAX14984 Technical data

Specifications and Main Features

Frequently Asked Questions

User Manual

General Description

Applications

Benefits and Features

Typical Operating Circuit

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

Test Circuits/Timing Diagrams

Figure 2. On-Loss

Typical Operating Characteristics

Pin Configuration

Functional Diagram

Detailed Description

5V Power Switch (S5V)

USB Switches and F1/F2 Outputs

RGB Switches

Horizontal/Vertical Sync Buffer

Applications Information

Power-Supply Decoupling

PC Board Layout

High ESD Protection

ESD Test Conditions

Human Body Model

Figure 3. Human Body ESD Test Model Figure 4. Human Body Current Waveform

Ordering Information

Chip Information

Package Information

Revision History