Trying to bring an old Ford car Stereo back to life and the DC-DC converter module is shot, electrolyte damaged the traces from leaky caps and one smd diode is disintegrated...no schematic to go by.
I do know it puts this output:
Is there something on the market as a kit etc, that can fit this spec?
Probably not without more information. Some questions which come to mind are: Does this car stereo have a model or other identification number on it? Does the converter module have its own part number or any identification numbers and if so what? What are the power requirements for the four rails mentioned above? Some pictures might help but no guarantee.
A visit to local junkyards might be more productive. Either looking for a complete replacement for the "stereo" or one from which you can pilfer the components.
Tubes, valves or transistors? Vibrator power supply? +30VDC is not a common voltage found in transistorized car radios. Same with DC to DC converters, unless it's designed to handle both negative and positive automotive ground systems.
Look around inside (and on the chassis) for a date. If you can't find or disclose the radio model number, perhaps having the date of manufacture will help narrow the search. This might also help:
Putting this to Google AI gets this:
The specific component you are looking for is the internal multi-rail power supply circuit (or voltage regulator IC) typically found inside Ford premium radio head units, such as the Ford Audio Control Module (ACM) from the Sony or Shaker premium sound systems.Where These Specific Voltages Are UsedIn a standard automotive environment, a vehicle's battery only supplies a single, nominal 12 VDC to 14.5 VDC rail. To power complex internal electronics, the car stereo utilizes an onboard step-up/step-down multi-channel power supply management IC (PMIC) to split and convert that single input into these exact sub-rails:± 5.0 VDC: Powers the digital logic, the main microcontroller unit (MCU), the USB ports, and the CAN-bus communication chips.± 8.0 VDC: Dedicated strictly to clean audio processing, including the AM/FM tuner circuitry, pre-amplifier stages, and Digital Signal Processing (DSP) operational amplifiers (op-amps).± 13.5 VDC: Replicates stable battery-level voltage to power the internal CD/DVD changer motors, display backlighting, and cooling fans.30.0 VDC: Generated by an internal DC-to-DC boost converter specifically to drive Vacuum Fluorescent Displays (VFD) or high-voltage liquid crystal display (LCD) bias gates.Common Integrated Circuits (ICs) to CheckIf you are repairing or testing a Ford stereo PCB board, look for the following multi-output automotive power supply ICs (often manufactured by STMicroelectronics or NXP) located near the main power input connector block:L9779 / L9780 Series: Automotive multi-voltage regulators commonly deployed in Ford infotainment platforms.ST75185 / TDA-series regulators: Multi-channel voltage regulators that manage 5V, 8V, and boosted display lines on a single chip.If you are trying to bench-test this Ford stereo outside of the car, note that you do not need a power supply that outputs all of these voltages. You only need to feed a standard 12V–13.8V DC (at least 5 to 10 Amps) power supply into the stereo's main harness pins (BATT+ and ACC/Ignition), and the radio's internal circuitry will generate the 5V, 8V, 13.5V, and 30V rails on its own.To help you find the exact schematic or chip placement, could you share the model number or part number (usually starting with letters like AA8T, BL3T, or HC3T) printed on the radio's metal sticker?
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If you identify the particular multi-rail regulator chip or chips, the manu will have an app note or datasheet typical from which inferring the schematic is a trivial exercise.
A retired Ford tech that worked at their service center back in the day and repaired hundreds of these.
He says leaked electrolyte eats the foil traces and sometimes the fine wire of the inductors.
He has a SM, but says this module is not shown in the schematics, as its proprietary.
Replace all electrolytics and check condition of inductors. Use the information you now have to check PCB trace integrity and the condition of any suspect semiconductors.
Ask the retired worker for the exact schematic or use the information here:
If necessary, search for another unit you can take parts from.
I'd probably obtain one of these because it may have useful parts and may be hackable to match exactly what you need even if it's the wrong physical shape/size.
Not going to happen on a good day. The lowest cost option is to replace the whole stereo assembly. You don't mention the year, but some of the generic replacements go back pretty far. And if not an exact replacement, it can be adapted to fit. The old circuit is not worth fixing, every part of it is on the brink of failure.
Will have my tech take a look.
Meanwhile, the blown "diode" may be marked N19, and could be like the others on the board, hard to say. N19 comes up in AI as a smd transistor, theres another one blown on the mainboard, so he has a bunch of them new on hand in case.
On the datasheet theres a diode near a pair of transistors, not sure if thats the location of the one thats blown, but apparently the buck boost coils use whats probably a GP type diode for that purpose? High speed switch maybe?
Not sure now if those were the correct outputs, there dont seem to be many pins to have that many.
Found out original Sony Part Number was: 1-466-025-14
Some sites list it but no stock.
Apparently Sony used this sort of design in an lot of gear, to drive displays in Camcorders and such....
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