Datasheet
LTC4307-1
1
43071fa
High Defi nition 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
specifi cation 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 fl ag 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.
■
HDMI
■
3.3V/5V Level Translation
■
Capacitance Buffer/Bus Extender
■
Bidirectional Buffer for Display Data Channel (DDC)
■
Compliant with HDMI Specifi cation 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
■
Compatible with Non-Compliant V
OL
I
2
C Devices
■
Isolates Input SDA and SCL Line from Output
■
Compatible with I
2
C
TM
, I
2
C Fast Mode and SMBus
■
READY Open-Drain Output
■
High Impedance SDA, SCL Pins for V
CC
= 0V
■
Small 8-Lead (3mm × 3mm) DFN and 8-Lead MSOP
Packages
APPLICATIO S
U
FEATURES
DESCRIPTIO
U
TYPICAL APPLICATIO
U
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 b
y
U.S. Patents
,
includin
g
7032051
,
6356140
,
6650174
LTC4307-1
GND
V
CC
SDAIN
SCLIN
1.8k1.8k
10k10k
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 600500
200mV/DIV
200
400
600
800
1000
43071 TA01b
SDAOUT
SDAIN
LOW
OFFSET