14 pin dip ceramic IC identification issue.

Papabravo

Joined Feb 24, 2006
17,316
They made resistor networks. There were two popular configurations:
  1. 7 resistors across the package.
  2. 13 pullups and 1 common.
Sorry, but the numbers don't suggest any obvious values.
 

Thread Starter

WSUBG

Joined Jun 12, 2021
30
Thank you for your reply Papabravo,
my DMM measurements indicate the following:
1623564065615.png
as a resistor network it makes no sense could this be a logic circuit?
 

Papabravo

Joined Feb 24, 2006
17,316
Thank you for your reply Papabravo,
my DMM measurements indicate the following:
View attachment 241159
as a resistor network it makes no sense could this be a logic circuit?
I do not think they (CTS) ever made a logic circuit. Given the lack of obvious markings it could be a custom part made for a single customer and purposely labeled that way to defeat you and all your efforts. There are lots of custom chips out there with OEM part numbers and no publicly accessible information.
 

MisterBill2

Joined Jan 23, 2018
9,904
On some devices it is possible to see a pattern of internal connections through the top ceramic layer. It would be a very slight set of ridges and valleys seen looking at the top from an angle with light reflecting off the top.
I do see in the second picture that there are quite a few of them, are they all the same number?There are date codes and model numbers and pin numbers on the tops.
Is the system working? In that case an analysis of functions could give you the data you seek. You might even be able to get dome data from CTS or singer.
It may also be that the IC devices are custom made, i which case you are out of luck.
 

MrSalts

Joined Apr 2, 2020
740
Your resistor network schematic is values you measured, not the values of the series/parallel resistors that are actually in the package. Your package likely looks like this inside.

4C704013-EED2-4B43-8234-CEDDFD625471.jpeg
 

Thread Starter

WSUBG

Joined Jun 12, 2021
30
On some devices it is possible to see a pattern of internal connections through the top ceramic layer. It would be a very slight set of ridges and valleys seen looking at the top from an angle with light reflecting off the top.
I do see in the second picture that there are quite a few of them, are they all the same number? There are date codes and model numbers and pin numbers on the tops.
Is the system working? In that case an analysis of functions could give you the data you seek. You might even be able to get dome data from CTS or singer.
It may also be that the IC devices are custom made, in which case you are out of luck.
Tank you for your input MisterBill2, device is not working properly the main suspects are the two quad op-amps responsible for preamplification of the analog signal that drives the linear actuators (so I think). The actuators do not respond to bight and feed selections, they simply hum/buzz in one spot. Analytical information is gathered from this reading BasicElectronics.pdf (tandtrepair.com) I have ordered the new NTE997 as recommended. My objectives other then fixing the machine are to learn how the position of the linear actuator is controlled. My approach was to identify location on the servo board where analog signal could be measured, (this is why I am retracing the board), then to replicate this signal with my own setup, then play with the signal and see what happens with the actuator. I am a senior in EE at WSU and this is my first attempt at such a thing so any input is appreciated.
 

MisterBill2

Joined Jan 23, 2018
9,904
Those are certainly ceramic. Always were!
And if the actuators hum and buzz I suggest evaluating the power supply. It might have open filter capacitors. and be suffering from high ripple. It might even have a failed rectifier diode. The secret to being good at diagnostics is to understand how the device works. That applies to industrial machines, most electronics, icecream freezers, and potato peelers. And other things as well. Know how it is supposed to be working, see how it IS working, Then decide what the cause must be.
 

Thread Starter

WSUBG

Joined Jun 12, 2021
30
Those are certainly ceramic. Always were!
And if the actuators hum and buzz I suggest evaluating the power supply. It might have open filter capacitors. and be suffering from high ripple. It might even have a failed rectifier diode. The secret to being good at diagnostics is to understand how the device works. That applies to industrial machines, most electronics, icecream freezers, and potato peelers. And other things as well. Know how it is supposed to be working, see how it IS working, Then decide what the cause must be.
I can see them, thanks to your suggestion with the lighting. I played with the camera and the lighting and voilà! I wonder if I shave the paint with some send paper would it be more clear? would I damage it? MisterBill2 you are a guru!
1623631523063.png
 

MrSalts

Joined Apr 2, 2020
740
The paint might not be too strongly adhered. You may be able to flake it off by getting an exacto knife or razor blade/razor knife under it - go little-by-little across the surface. Ultimately, you can recreate the part with SMD resistors if needed. By the way, what's the goal here?

The network is right next to a quad op amp (or quad comparitor) so trace the paths of the copper to each pin a nF recreate the amplifier, filter, oscillator circuit. Note that there are four networks with different part numbers, you're going to have to figure out the resistor network in each. Good luck.
 

Thread Starter

WSUBG

Joined Jun 12, 2021
30
The paint might not be too strongly adhered. You may be able to flake it off by getting an exacto knife or razor blade/razor knife under it - go little-by-little across the surface. Ultimately, you can recreate the part with SMD resistors if needed. By the way, what's the goal here?

The network is right next to a quad op amp (or quad comparitor) so trace the paths of the copper to each pin a nF recreate the amplifier, filter, oscillator circuit. Note that there are four networks with different part numbers, you're going to have to figure out the resistor network in each. Good luck.
The goal is to replicate the circuit on my Analog Discovery Studio and learn how the position of the linear actuator is controlled, and attempt to control it actuator is in the picture Fig1B in the beginning of the thread.
 

MisterBill2

Joined Jan 23, 2018
9,904
I can see them, thanks to your suggestion with the lighting. I played with the camera and the lighting and voilà! I wonder if I shave the paint with some send paper would it be more clear? would I damage it? MisterBill2 you are a guru!
View attachment 241209
That is a THIN ceramic coating andit should not be abraded because it is protecting the thin-film resistors printed on the substrate underneath. Or iit might be thick-film resistors, I don't recall at this moment.
And while the whole thing seems strong, they are quite brittle and they will break with too much force, not sturdy like IC devices.
 

MisterBill2

Joined Jan 23, 2018
9,904
After the external portions of the circuit board are documented, and the desired functions known and understood, it is entirely possible to replace these DIP assemblies with 14 pin dip headers and add resistors and capacitors to the headers to provide whatever function is desired.
But still, the very first thing to check will be the power supply portions of the system. The power supply affects the whole system and also is the easiest to check. to
Do you have the model number and pin-outs for the ICs? And what sort of sensors does the machine use?
I am thinking that these machines are more prone to mechanical problems than electronic failures. Do the actuators that hum and buzz operate smoothly when you activate them by hand? That cn be an issue some times. But still, check the power supply voltages first. But be cautious if there is no mains transformer.
 
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MrSalts

Joined Apr 2, 2020
740
The biggest mystery is the microcontroller under the black blob of epoxy (next to the word, BIGHT, on the PCB. It doesn't really matter what anything else does, that is the brain.
 
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