HISTORY:
Similar to the ECG1550
Interesting device from Hitachi, not only the functionality but the very strange packaging/pin numbering system.
The package at first appearances looks like a standard DIL plastic package, 20 pins but then you notice that two pins are missing (what would normally be called pin 11 & 20) - this is intentional and part of the package design.
Stranger though is the pin numbering system, the first pin is not 1 as you may expect but in fact 17! Then the numbering is standard 1 ~ 8 but the pin next to 8 is 18! See the diagram I have extracted from the datasheets for a clearer explanation. It seems that Hitachi referred to this package as a DIL 16-2
As to the functionality, these chips are from the days of CRT analog signal processing in televisions but ALSO arcade machines from long ago and that interesting pin called X-Ray input is the horizontal oscillator shut down input.
Straight from my "vintage spare parts" section of the old workshop stores, this is a NEW device, but of course very old stock which has been stored on ESD foam to keep the pins safe, it is not a CMOS device.
HITACHI - Special Function IC
Type: HA11235
20 pin DIL plastic but with two pins intentionally not present - see one of the photographs
Package is called a DIP 16-2
Function: Synchronous signal processing system
Full specifications/block diagrams/application notes are readily available online
COSMETIC CONDITION:
NEW
CLEAN
NO bent legs!
Light oxidisation to the legs, not brilliantly shiny any longer but just a slight dullness and still perfectly useable.
This chip has been stored on ESD Black foam, to protect the legs and will be supplied in the same type of packaging.