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What set ALM apart from other wideband controllers?



There are tons of wideband controllers in the market now. People often ask: what makes your wideband controller better than others? In short:

ALM is the OE equivalent while others are after-market products.

First, ALM uses LSU4.9 or LSU ADV sensors, while most other widebands still use LSU4.2 sensors or just LSU4.9 sensors. For details of difference of the LSU ADV, LSU4.9 vs. LSU4.2, see here:
Why LSU 4.9 is superior to 4.2
By the way, there were a lot of debates on LSU4.9 vs LSU4.2 sensors, about “how old technologies were better than the newer ones”. After Ecotrons selling LSU4.9 widebands for many years, people start to believe that the LSU4.9 is superior to the LSU4.2 sensor. And some wideband manufacturers who denied the advantages of the LSU4.9 before quietly move to LSU4.9 sensors. But again, Ecotrons takes the lead to move to the next level, LSU ADV sensors, the latest and greatest wideband technology.


ALM uses Bosch CJ125 chip

CJ125 is the application specific integrated circuits (ASIC) designed for LSU Sensors. With CJ125 chips, ALMs control the sensor temperature in the close loop mode and precisely keep the LSU4.9 sensor at 780 degree C. In fact, Bosch uses this chip for every LSU sensor. The CJ125 and LSU sensor are mated-pair by Bosch. Presumably LSU sensors work the best with CJ125 chips.
Quoted from Bosch LSU sensor data sheets: “The wide band sensor LSU operates only in combination with a special LSU control unit (CJ125 ASIC). The functional characteristics given in this document are only valid for operation with the CJ125 according to module specification and with recommended operational parameters.”
Bosch’s own wideband controller, “LambdaTronic, or LT4”, uses the CJ125 driver chip.

Note: CJ125 chip is the best practice of Bosch O2 sensor control circuits, but it is still just a hardware circuit. Without a good software, it will not work well. Ecotrons was born from auto industries, and it has the expertise and know-how on using CJ125 to control LSU sensors.


ALM supports CAN bus

CAN bus communication is the professional data exchange method for automotive control systems, period. Especially for engine controls, an engine control unit (ECU) transmits and receives tons of data on the CAN bus, and one part is the Lambda / O2 concentration from the wideband controller. CAN bus communication eliminates the DAC (Digital to Analog Converter) and then ADC (Analog to Digital Converter) conversions, therefore eliminates 2 big error sources, and keeps the original signal accuracy. 0-5V analog circuits can easily introduce in +/- 0.02V errors, which can be equivalent to 0.01 lambda error. All wideband controllers’ 0.01 lambda accuracy is questionable if they are using 0-5V analog outputs. Compared to the CAN bus, 0-5V analog output is an amateur method.
Note: ALM’s 0-5V analog output is factory calibrated for each unit to minimize the errors caused by the circuits.
Click here for:
ALM-CAN product and spec.


ALM uses Freescale’s 16 bit micro-controller

Freescale (now NXP) is the largest automotive semiconductor manufacturer in the world. Their micro-controllers, or in short, micros, are used for decades in auto industries. Most, if not all, other wideband controllers use micros from consumer electronics industry. The micro is the heart of any controller, like the CPU of your computer. It determines almost everything of the controller. Auto-industry rated micro has higher standards than the consumer electronics. The manufacture process of auto-rated micros costs more than consumer electronics. Naturally, auto-rated micros are more expensive. Most wideband manufacturers choose consumer electronics because of 2 reasons: 1) they are cheaper; and 2) they are easier to program (lower bar). Most end users don’t really understand the difference, but, use common sense please: automotive electronics work in much worse environments than the consumer electronics. Auto-electronics must work in harsh conditions, like cold, hot, wet, and / or salty weathers, and severe vibration, EMI noises; you name it. Consumer electronics just need to work in your room, or it is acceptable to derate in a harsh environment. While people can just re-boot a laptop if it runs into a “blue-screen”; people cannot afford a car crash caused by a glitch of the auto-electronics. This tells you the difference between the auto-electronics and consumer electronics.
Freescale S12 16-bit micro family is fast, cost effective, with high quality. Here is the info for this micro family:
Freescale’s S12P micro family


Many other smaller points…