Updated: February 2009Infineon Controller Hardware Settings
I am posting this thread as an Infineon controller knowledge base. The purpose here is to assist userÃ¢â‚¬â„¢s understanding of the features available on the Chinese-made Infineon digital controller. Please feel free to PM (Knuckles) with discrepancies or technical errors that may be evident in this post.
The Infineon (http://www.infineon.com
) Micro Control Unit (MCU
) is the heart of the controller printed circuit board (pcb). The MCU currently in use by the Chinese pcb vendor is the XC846 chip. The pcbÃ¢â‚¬â„¢s come in 6, 9, 12, and 18 mosfet versions. This thread is particular to the 12-mosfet pcb (although the 18-FET controller is also available). The XC846 MCU and the PWM programming has proven sufficient to drive virtually any motor (including geared motors like the PUMA and BMC) commonly used in electric scooters and e bikes. Â· Standard Wiring http://126.96.36.199/endless-sphere/Infineon_Wiring.jpg Â· Mosfets
Mosfets are the switches that channel the flow of current for BrushLess Direct Current (BLDC) Pulse Width Modulation (PWM). The choice of mosfet is primarily driven by cost and performance characteristics. As a rule of thumb, more expensive mosfets have a high voltage tolerance and a lower Ã¢â‚¬Å“ONÃ¢â‚¬Â resistance and are therefore capable of handling more voltage and amperage. The consumer thus has the option to use the most cost effective controller for their specific electric vehicle (EV) application.
Currently, the 12-FET Infineon is available with the following mosfets (of increasing cost) Ã¢â‚¬Â¦ Â· 75nf75
Specifications http://188.8.131.52/endless-sphere/75nf75.pdfÂ· 80nf10
Specifications http://184.108.40.206/endless-sphere/456 ... 80NF10.pdf
(Temporarily Discontinued)Â· irfb4310
Specifications http://220.127.116.11/endless-sphere/232 ... FB4310.pdf
In general, the 75nf75
mosfets are good for 30 Amp controllers up to 72V nominal.
mosfets are more appropriate for controllers up to a 50 Amp current limit. Â· Capacitors
Notice that there are two 100V 470uf
main capacitors across the main battery + and - mosfet leads.
A third 100V 470uf
capacitor is located 2/3 rd way along the "mosfet bus" on the "high side" of the current shunt.
These capacitors are essential to reduce voltage spikes to the mosfets during PWM motor control.
btw ... The production runs of Infineon pcb's are Date Stamped. The pcb shown in this image is dated "20080822".
I also verify the mosfets of each controller and measure the shunt value in mOHMs. Â· R12
The Low Voltage Cut-off (LVC) circuit consists of tiny surface mount transistors and one capacitor.
This circuit connects to an MCU pin-out so the MCU can detect the battery voltage.
The R12 resistor is about 1.2 kohm and connects from the MCU pin-out to ground.
R12 can be disabled and replaced with a potentiometer to allow any LVC value.
It is critical, however, that the LVC protects the controller from a low voltage condition.
If the voltage to the mosfet drivers and MCU is not steady the controller will be damaged. Â· R44
The R44 circuit contects to the high side of the shunt.
This circuit connects to an MCU pin-out so the MCU can detect the shunt current. Â· R01(A,B)
The R01 (A & B) are slots for the power resistors. The selection of these resistors is critical.
They drop the voltage down from the battery voltage to a safe value for the LM317 voltage regulator.
During controller operation, the current thru these resistors is 65 ma (0.065 amps).
Each 100 ohm of resistor value will drop the battery voltage by 6.5 volts.
The choice of resistors is selected by the choice of LVC to prevent controller damage. Â· R6
The R6 resistor is a bridge (shunt) across the LM317 V(in) and V(out).
It is provided to cap the voltage drop across the LM317 to no more than 40V.
The choice of this resistor is critical because it provides the voltage "window" of the battery.
If R6 is too small the voltage window will be too small. If R6 is too large the LM317 can be damaged. Â· LM317
The LM317 on the pcb is configured as a voltage regulator with V(out) = 12 volts.
Small capacitors near the LM317 reduce voltage spikes in the 12 volt output.
This feeds the 12 volt bus on the pcb. The 12 volt bus powers that mosfet drivers.
According to specification the voltage drop across a LM317 should not exceed 40 volts.
The controller LVC should never be set so low that the 12V bus drops below 12V.
It should be noted, however, that the R6 resistor Ã¢â‚¬Å“relievesÃ¢â‚¬Â the heat load from the LM317.
If R6 is removed, all 65 milliamps of current will flow thru the LM317.
If the voltage drop across the LM317 is 15 volts then it will generate 1 watt of heat.
If the voltage drop across the LM317 is 30 volts then it will generate 2 watts of heat.
This heat will cause the LM317 to shut down since it has internal thermal protection.
There is no heat sink on the LM317.
But when R6 is installed, it will draw some of the 65 milliamps of current away from the LM317.
Using R6=660 ohm, a 6.6 V voltage drop across R6 will pass 10 milliamps of current.
The LM317 is now only passing 55 ma.
A 13.2 V voltage drop across R6 will pass 20 milliamps of current. LM317 now passing 45 ma.
A 19.8 V voltage drop across R6 will pass 30 milliamps of current. LM317 now passing 35 ma.
A at 40 V voltage drop, R6 will pass all 65 milliamps of current. LM317 is now passing zero current.
But a high voltage drop across R6 will also cause the 12V bus to rise above 12 volts.
The 12V bus can climb as high as 15V or even 16V.
The 5V bus can climb as high 6V. Â· 7805
The 7805 is a fixed 5 volt regulator and feeds the 5 volt bus on the pcb.
The 5 volt bus feeds the MCU and the throttle and motor hall sensors. Â· Shunts
The latest Infineon pcb is fitted with a consistent shunt.
The standardized shunt value is approximately 3.8 mOHM. Â· RECOMMENDATIONS
I recommend the following resistor settings for the Infineon controller.
These values will ensure safe controller operation for the voltage range indicated.
R6 = 2 x 330 ohm (2W) = 660 ohm (4W) on all controllers.
R6 = 1 x 680 ohm (3W) on all controllers.
Nominal Battery Voltage = 24V
LVC = 20 volts
R01(A,B) = bypass
Maximum Safe Operating Voltage = 50 volts
Nominal Battery Voltage = 36V
LVC = 30 volts
R01A = 100 ohm (2W)
R01B = 100 ohm (2W)
Maximum Safe Operating Voltage = 60 volts
Nominal Battery Voltage = 48V
LVC = 40 volts
R01A = 180 ohm (2W)
R01B = 200 ohm (2W)
Maximum Safe Operating Voltage = 70 volts
Nominal Battery Voltage = 60V
LVC = 50 volts
R01A = 200 ohm (2W)
R01B = 330 ohm (2W)
Maximum Safe Operating Voltage = 80 volts
Nominal Battery Voltage = 72V
LVC = 60 volts
R01A = 330 ohm (2W)
R01B = 330 ohm (2W)
Maximum Safe Operating Voltage = 90 volts