LTC4307-1

1

43071fa

High Definition Multimedia

Interface (HDMI) Level-

Shifting 2-Wire Bus Buffer

The LTC4307-1 is a 2-wire bus buffer that provides ca-

pacitance buffering between input and output. The HDMI

specification requires that devices have less than 50pF of

input capacitance on their DDC bus lines. The LTC4307-1’s

capacitance buffering feature, in conjunction with its

sub-10pF data and clock input capacitance, allows HDMI

components to easily meet the 50pF requirement and

tolerate high capacitance on the internal bus.

The LTC4307-1 also provides level-shifting between 3.3V

and 5V systems to allow lower voltage HDMI transmitters,

receivers and EEPROM to interface to the 5V DDC bus.

READY is an open-drain digital output flag that indicates

whether or not the input and output busses are connected

and can interface to the HDMI hot plug detect (HPD) signal.

When driven high, the ENABLE digital input allows the

LTC4307-1 to connect after a stop bit or bus idle. Driving

ENABLE low breaks the connection between the input and

output busses.

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HDMI

■

3.3V/5V Level Translation

■

Capacitance Buffer/Bus Extender

■

Bidirectional Buffer for Display Data Channel (DDC)

■

Compliant with HDMI Specification Version 1.3

DDC Capacitance Requirement

■

Level Translation Between 3.3V and 5V

■

±5kV Human Body Model ESD Protection

■

60mV Buffer Offset Independent of Load

■

■

Isolates Input SDA and SCL Line from Output

■

■

READY Open-Drain Output

■

■

Small 8-Lead (3mm × 3mm) DFN and 8-Lead MSOP

Packages

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

Rising Edge from Asserted Low

, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.

All other trademarks are the property of their respective owners.

Protected by U.S. Patents, including 7032051, 6356140, 6650174

LTC4307-1

GND

SDAIN

SCLIN

1.8k

1.8k

10k

10k

0.1μF

43071 TA01a

3.3V

5V

DDC GROUND

TV (SINK)

DVD PLAYER (SOURCE)

<50pF

HDMI RX

IC

HDMI

CABLE

EEPROM

SDAOUT

SCLOUT

ENABLE

μC

HDMI TX

IC

100ns/DIV

0

0

100

200

300

400

600

500

200

400

600

800

1000

43071 TA01b

SDAOUT

SDAIN

LOW

OFFSET