ADV7170/ADV7171
Input/
Output Description
Pin No.
Mnemonic
35
SCRESET/RTC
I
This pin can be configured as an input by setting MR22 and MR21 of Mode Register 2.
It can be configured as a subcarrier reset pin, in which case a low-to-high transition on this
pin resets the subcarrier to Field 0. Alternatively, it may be configured as a real-time control
(RTC) input.
36
37
44
TTXREQ
TTX
O
I
Teletext Data Request Signal. Defaults to GND when teletext not selected. Enables
backward compatibility to ADV7175/ADV7176.
Teletext Data. Defaults to VAA when teletext not selected. Enables backward compatibility
to ADV7175/ADV7176.
TTL Clock Input. Requires a stable 27 MHz reference clock for standard operation.
Alternatively, a 24.5454 MHz (NTSC) or 29.5 MHz (PAL) can be used for square pixel
operation.
CLOCK
I
Rev. C | Page 12 of 64
ADI [ ADI ]
