Preliminary
THCV245A_Rev.0.90_E
Copyright©2020 THine Electronics, Inc.
THine Electronics, Inc.
Security C
6/67
6
Functional Description
6.1
Functional Overview
THCV245A can receive MIPI CSI-2 video and transmit it to over 15m length. With High Speed CML SerDes,
high reliability and robustness encoding scheme and CDR (Clock and Data Recovery) architecture, the
THCV245A enables to transmit RAW/YUV/RGB/JPEG/Generic8bit data through Main-Link by single 100ohm
differential pair or 50ohm Coax cable with minimal external components. Maximum supported resolution is
horizontal active 3840 pixels format. In addition, the THCV245A has Sub-Link which enables bi-directional
transmission of 2-wire serial interface signals, GPIO signals and also HTPDN/LOCKN signals for Main-Link
through the other 1-pair of CML-Line. The THCV245A system is able to watch peripheral devices and to control
them via 2-wire serial interface or GPIOs. They also can report interrupt events caused by change of GPIO inputs
and internal statuses such as CRC error.
6.2
Reference clock supply
Reference clock supply CKI is required since MIPI CSI-2 clock stream will not always be continuous.
CKI frequency examples are 24MHz, 27MHz and 37.125MHz.
To supply the same oscillator clock as CMOS sensor to THCV245A is recommended.
See Figure 1.
Physical layout artwork of oscillator clock trace is supposed to be designed to shorten stub branch as possible.
Figure 1.
Reference clock supply basic method
Another alternative is to make use of THCV245A CKO internal clock buffer function.
CKO clock buffer may strengthen clock drive ability in order to compensate clock signal loss in large structure.
On the other hand, additional clock buffer may become another EMI emission source as trade-off.
Figure 2.
Reference clock supply clock buffer method (optional)
THCV
245A
CMOS Sensor
CKI
CKO
OSC
MCLK
St ub
*
*Stub branch of OSC clock trace
must be as short as possible for
signal integrity.
THCV245
A
CMOS Sensor
CKI
CKO
OSC
MCLK
(good) large structure available
(bad) rather high EMI emission
can be long
