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high side and low side driver module - TC4427

Posted: Mon Jan 27, 2014 6:42 pm
by kb1gtt
The high side and low side driver module based on TC4427 has been created.
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This module has a place where you can wire the high side voltage, like 3.3v, 5v or 12v and it will either drive to this high voltage or it will drive to GND. This includes 6 channels and is handy for a variety of ignition options.

SVN repository
Full archive
Schematic.pdf
Mouser BOM

Re: high side and low side driver module

Posted: Mon Jan 27, 2014 6:58 pm
by AndreyB
I will order this to see how it would work with the Nissan COP, the one with build-in igniter.

Re: high side and low side driver module

Posted: Fri Feb 28, 2014 1:13 pm
by AndreyB
non-fatal issue with rev 0.1: the part number is for SOIC package but the board has MSOP package. Part number should be TC4427AEUA for MSOP package.
In the next revision we will probably go to a larger package which is TC4427ACOA (SOIC package)

Re: high side and low side driver module

Posted: Fri Feb 28, 2014 2:18 pm
by puff
is this just for ignition purposes?

Re: high side and low side driver module

Posted: Fri Feb 28, 2014 7:05 pm
by kb1gtt
It's primary purpose is for ignition, but it can technically be used for other things if software is written for it. I'm not very crazy about the 7 ohms thing. It would be nice if we could find a similar chip with a lower Rds.

Re: high side and low side driver module - TC4427

Posted: Thu May 01, 2014 8:41 pm
by shredator
so how is this different from the injector driver module? can this thing drive a coil without an igniter?

Re: high side and low side driver module - TC4427

Posted: Thu May 01, 2014 8:48 pm
by AndreyB
shredator wrote:so how is this different from the injector driver module? can this thing drive a coil without an igniter?
Injector driver is low-side, and ignition modules want high-side. No, this module is not tough enough to drive a coil directly.

Let's let someone more qualified to comment on using this module to drive injectors.

Re: high side and low side driver module - TC4427

Posted: Thu May 01, 2014 8:50 pm
by kb1gtt
Injector drivers are typically low side drive, this is high side and low side drive, or also some times known as push and pull vs just pull.

No this can not drive inductive loads like injectors or ignition coils as it does not have proper protection.

Injectors will clamp the inductive load typically around 30V to 80V and Ignition will typically clamp the primary side kick back to 400V to 600V. This chip can not preform either, so it can not directly drive either chip.

This chip is good for external ignition drivers that require 12V instead of 5V, or if the external driver requires both push and pull configurations.

Re: high side and low side driver module - TC4427

Posted: Thu May 01, 2014 8:53 pm
by AndreyB
kb1gtt wrote:This chip is good for external ignition drivers that require 12V instead of 5V
Instead of 3.3V? Since we are a tiny 3.3 MCU...

Re: high side and low side driver module - TC4427

Posted: Wed May 14, 2014 12:47 am
by UnaClocker
You would typically fire off a coil that doesn't have an internal ignitor with an IGBT (insulated gate bipolar transistor).
Injectors can be driven off a BJT or a Mosfet, NPN either way. There are a lot of options for injector drivers.

Re: high side and low side driver module - TC4427

Posted: Thu Aug 14, 2014 2:57 pm
by AndreyB
Finally digikey has TC4427ACOA in stock! This helps a bit :)

Re: high side and low side driver module - TC4427

Posted: Wed Dec 28, 2016 5:10 am
by AndreyB
low-side does not work great with a gauge cluster bulb
[video][/video]

Re: high side and low side driver module - TC4427

Posted: Wed Dec 28, 2016 8:46 am
by puff
is it because of the PWM on that pin or because of the lack of current?

Re: high side and low side driver module - TC4427

Posted: Wed Dec 28, 2016 6:03 pm
by kb1gtt
Why are you using the hi/low driver for the MIL? It appears it should be a low side drive with some dash MCU controlling when it's turned on. What happens if you short that low side to the battery negative? Can you do this short with the meter in the DC amps scale, such that you can measure how much current the light uses? Also using the amps scale typically includes a fuse which would blow and potentially protect your dash if you happened to short something that shouldn't be shorted.

Re: high side and low side driver module - TC4427

Posted: Wed Dec 28, 2016 6:07 pm
by kb1gtt
It appears your external light is a high side load. This is then powering the LED. You may be over driving the chip, and when it's driving the light it may be generating a voltage drop across the chip. When this happens the light is half dim. I would expect the dash light is brighter when the ECU light is dim.

How many amps is that light attempting to consume?

Re: high side and low side driver module - TC4427

Posted: Wed Dec 28, 2016 6:21 pm
by AndreyB
The MIL is a low-side control for sure
1) I've tried grounding that wire and that gave me a proper bright MIL
2) http://rusefi.com/wiki/index.php?title=Vehicle:Mazda_Miata_2003 confirms low-side control

I am trying high-low because in case of 2003 miata we are getting closer to run out of low-side drivers
1-2-3-4 injector
5 main relay 6 fuel relay
7 IAC 8 VVT 9 radiator fan 10 boost control

Re: high side and low side driver module - TC4427

Posted: Thu Dec 29, 2016 1:43 am
by kb1gtt
Is the hi set to 12V or is that floating AKA no jumper for that particular chip.

Also when using the meter to jump it to GND. What is the measured current.

Re: high side and low side driver module - TC4427

Posted: Thu Dec 29, 2016 2:23 am
by AndreyB
P607 floating
90mA to GND for a bright MIL

PS: so a 1W bulb?

Re: high side and low side driver module - TC4427

Posted: Thu Dec 29, 2016 2:57 am
by kb1gtt
R613 or equiv is probably screwing you. That's probably limiting you to 50mA. Can you bypass it some how for a test?

Re: high side and low side driver module - TC4427

Posted: Thu Dec 29, 2016 3:51 am
by AndreyB
Much better without R613! I want to say it's not as bright as direct to GND but still pretty OK.

Only thing looks like I need inverted control signal but looks like firmware does not want to accept the inverted setting. Blinking works fine with bench test but the MIL stays on before and after test.

Re: high side and low side driver module - TC4427

Posted: Thu Dec 29, 2016 10:43 am
by kb1gtt
Keep in mind the Frankenso light is going to be inverted from the dash light.

So 12V/0.09A = 133ohms. The TC4427 has an internal resistance of about 7 ohms, so when this chip is used that's 12V/140ohms = 0.085A. So about 5mA less current. I expect this is the difference in brightness. Less current means less light. Also when the engine is running it wold be 14V/140ohms = 0.10 amps so it should get brighter.

Also that light is probably going to be fatigued a bit as LD607 is going to conduct 5mA. So the light is switching from 100mA to 5mA. To prevent this 5mA current from burning out your dash light, you probably want to remove R614, such that you disable the ECU light.

Re: high side and low side driver module - TC4427

Posted: Fri Jan 06, 2017 12:07 am
by puff
found this doc somewhere on the net (hope, I'm not infringing someone's copyrights) - could be useful.

Re: high side and low side driver module - TC4427

Posted: Thu Jan 26, 2017 3:21 pm
by AndreyB
Horsty wrote:am i right that i can use the tc4427 for the injectors switching ground on inverting mode in tunerstudio?
Aren't these too small for injectors? So far we've only used tc4427 for high-side lower-current logic level coils, and a little bit for small dashboard bulbs.

Re: high side and low side driver module - TC4427

Posted: Thu Jan 26, 2017 3:39 pm
by Horsty
the bosch EV6 injectors im using have a resistance from 12 to 15 ohms. therefore a max current i think about 1,2A at 14,5V max.
so it should be fine if i add a flyback diode to the injector coil? -> tc4427 in dip package is rated to 1,5A

btw: if i have to use the 14NV04... is there a need of a heatsink?

Re: high side and low side driver module - TC4427

Posted: Thu Jan 26, 2017 7:02 pm
by kb1gtt
Yes they are too small. They claim to do more amps, but thermally they can not do the amps claimed in the datasheet. You would need to pay very close attention to make sure you can get the heat out.

Re: high side and low side driver module - TC4427

Posted: Thu Jan 26, 2017 8:56 pm
by Horsty
okay. thank you.

Re: high side and low side driver module - TC4427

Posted: Fri Jan 27, 2017 1:38 pm
by Rhinoman
The TC4427 isn't designed to drive loads, its meant to drive MOSFET gates where you need a high current for a very short time only to charge or discharge the gate capacitance. At a maximum ambient temperature of 85C the average current must be less than around 200mA to avoid overheating.

Re: high side and low side driver module - TC4427

Posted: Mon Apr 10, 2017 1:29 am
by stefanst
Interesting fact on the hi-lo drivers:

Without pullup to either 12V or 5V, they default to being Low-side drivers- correct?
Well, they will still drive my coils and my alternator (both hi-side drive), even without pullup. I forgot to install the pullups and the car ran just fine anyway. Scoped the signal on the coils and when the coils were supposed to spark we had about a 4ms or so dwell and then ignition. But we only were running at about 1V. Apparently enough to drive the coils. Same for alternator PWM- works just fine.
We only found that there is a problem at all, because my tachometer which is also hooked up to hi-lo drive didn't come on. @ hypothesized that the driver wasn't driving enough voltage. And since he didn't see the LEDs flashing, the reason was obvious.

So: Why are my coils firing and is my alternator producing current even without being hi-side driven?

Re: high side and low side driver module - TC4427

Posted: Mon Apr 10, 2017 10:02 am
by kb1gtt
I do not know your circuit, so I'm making WAG's instead of SWAG's. Here are a couple of possibilities.

Commonly igniters have a internal pull-up resistor. However you mention it only pulls up to 1V, so I doubt this is the situation. However it's possible that internal to the igniter you have a 1M pull-up, and it's possible the TC4427 has a 100k pull down impedance when floating. The equivalent resistor divider could make for a 1V-ish signal. It is common that MOSFET's trigger at 0.8V, so it's possible that the MOSFET portion of the IGBT is being activated by 1V.

Your igniter is probably an IGBT. There is probably some leakage from the transistors, that trickles some nA's to the gate. This commonly happens until the MOSFET portion of the IGBT turns on and discharges the transistor part of the IGBT. This is why you commonly have that pull down resistor added to the driver circuit. That pull down adds assurances that the IGBT will turn off when it's not being driven. Basically some nA's across a 1k or 5k pull down ='s a small voltage which means the IGBT is turned off. This is the likely situation. I would not relay on this as the leakage current varies with temperature, age, batch tolerances, ect.

The real concern I have with this is that you may not be able to turn your igniter off. This won't cause false ignition events, but it could burn up your igniter or coil. I would suggest adding a pull down resistor such that a floating condition like when the ECU is powered off, will result in the igniter being turned off.

I'm less familiar with alternator drivers, but this is likely the same situation. There is likely some leakage that allows it to self power. I would also add a pull down here to ensure that when you turn off the ECU you don't fire your electronic bits.

Re: high side and low side driver module - TC4427

Posted: Sat Mar 09, 2019 9:37 pm
by AndreyB
I've recently made some scary changes to this PCB at https://github.com/rusefi/hw_modular/tree/master/highside_module to switch it into the Manhattan double row format.