Author Topic: Analog TV tuner datasheet? (probably) ALPS TMDG2-731A  (Read 1443 times)

0 Members and 1 Guest are viewing this topic.

Offline YansiTopic starter

  • Super Contributor
  • ***
  • Posts: 3930
  • Country: 00
  • STM32, STM8, AVR, 8051
Analog TV tuner datasheet? (probably) ALPS TMDG2-731A
« on: July 31, 2019, 12:54:34 pm »
Hello,

today sifting through some trash, I found a tuner from a VCR set, the TMDG2-731A, probably made (or designed) by ALPS.

I have quickly found a couple of service manuals including schematics, so I know the basic pinout. However, the tuner requires I2C control. Is there any standard to this or any chance finding the documentation?

I have cracked it open to see the IC names, however those bastards from ALPS even re-branded the chips, so I only got some ALP029, ALP018TT and ALP115, even though it seems that each of the chips were a completely different manufacturer (considering the style of the package and font). Not very telling. Rebranding chips shall be a crime!

Is the tuner worth keeping (considering a suitable documentation for the control will be found) or shall I put it back into trash with others alike? (... and put the trash where it belongs)

Thanks for any hints how to ID the sucker.
Y.
 

Offline YansiTopic starter

  • Super Contributor
  • ***
  • Posts: 3930
  • Country: 00
  • STM32, STM8, AVR, 8051
Re: Analog TV tuner datasheet? (probably) ALPS TMDG2-731A
« Reply #1 on: July 31, 2019, 03:32:12 pm »
SO i thought: what about turning with a package type and brief IC description to a google?

After a couple mins on google, I have found the main tuner/synth IC may be Texas Instruments SN761672. The pinout (at least GND pins and I2C pins) match. However, having a series resistance of 390ohm in SCL and about 800ohms in SDA looks kind-of weird, the paths still match the pinout from the service manual and pinout of the tuner IC.  SDA goes to SDA, SCL goes to SCL,  AS goes to AS.


Okay, found one finally, see attached datasheet of the IC.   So one down, two remaining.


« Last Edit: July 31, 2019, 04:45:50 pm by Yansi »
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf