Super strong driving capability and perfect protection function! Naxin Micro releases new driver NSi66x1A/NSi6601M

July 19, 2022 - Naxin Micro released two new single-channel isolated gate drivers, NSi66x1A and NSi6601M, both of which are suitable for driving power tubes such as SiC, IGBT and MOSFET. They have both automotive grade (meeting AEC-Q100 standard) and industrial grade, and are widely used in new energy vehicles, air conditioners, power supplies, photovoltaics and other application scenarios.

NSi66x1A--Intelligent isolation single-tube driver with protection function (NSI6611A/NSI6651A)

Product Features

• Super strong driving capability, can provide a maximum of 10A source and sink current capability, support rail-to-rail output and separate output

• Complete protection functions: DESAT short circuit protection, fault soft shutdown, Maitreya clamp, undervoltage protection; when short circuit fault or undervoltage occurs, feedback can be given through a separate pin report

• The input and output ends adopt dual capacitor reinforced isolation technology, plus Nanochip Adaptive OOK coding technology, with a minimum common mode transient immunity (CMTI) of up to 150kV/μs, which improves the robustness of the system.

• The driver side power supply voltage VCC2 is up to 32V, and the input side VCC1 is powered by a 3V to 5.5V power supply voltage; both VCC1 and VCC2 have undervoltage protection (UVLO)

• Extremely low transmission delay, as low as 80ns

• NSi6611 supports ASC feature, which can force the output to high in emergency.

• Working temperature: -40℃ ~ 125℃

• RoHS compliant package type: SOW16

Functional Block Diagram

NSi66x1A has super strong driving capability, effectively saving peripheral circuits

In high-power applications, users generally choose high-power tubes such as IGBT and SiC, so the Qg of the power tube will be larger, and the requirements for the product's driving current capability will become higher.

NSi66x1A can provide a maximum 10A current capability. Compared with traditional solutions, it does not require an additional buffer circuit and can directly drive high-power tubes. It saves the cost of the buffer circuit and the size of the PCB, and does not require an additional circuit for matching, which increases the stability of the system. In addition, NSi66x1A has an internal integrated Maitreya clamp, supports separate output, is easy to use, has fewer peripheral devices, and highlights the cost-effectiveness.

Application circuit diagram using NSi66x1A solution

Traditional drive circuit diagram in high power applications

NSi6611A supports ASC function

What is ASC?

ASC, or active short circuit, is a safety protection mechanism for the motor system. It short-circuits the UVW three-phase of the motor (by switching the power tubes to achieve short-circuit of the upper three bridge arms or the lower three bridge arms).

NSi6611A supports the ASC function. When the motor is running at too high a speed or when other abnormalities such as sudden braking occur, the three-phase short circuit can be used to reduce the motor's internal current consumption and the back electromotive force generated by the motor so that it does not exceed the bus voltage provided by the high-voltage battery, ensuring that the power battery, bus capacitors and other high-voltage devices are not damaged, thereby protecting the motor and electrical system.

The NSi6611A pin1 is the ASC function. As shown in the ASC timing diagram below, even when the input is low or VCC1 is undervoltage, when the pin1 level is high, the ASC function will be enabled, OUT will be forced to output high, and the power tube will be turned on. Of course, if the user does not need the ASC function, the NSi6611A pin1 can be left floating or pulled down to GND2.

NSi6611A ASC Timing Diagram

Case details

In order to realize the ASC function of the system, the tube driver IC of the UVW three-phase lower bridge arm can use three NSi6611A, connect their pin1 together, and name the connection point "ASC Trigger". The voltage at this point is low by default. When the system detects a fault, such as when the bus voltage is too high, the external trigger signal makes the "ASC Trigger" high. At this time, the three NSi6611 will force the tubes of the UVW three-phase lower bridge arm to open, so as to short-circuit the three lower bridge arms of the motor and realize the ASC function. The NSi6611A is externally triggered by the "ASC Trigger" to a high level until the chip OUT is forced to output high, and the time is 0.66us (tASC_r), which responds quickly and protects the system in time.

NSi6601M--High reliability isolated single-tube driver with Maitreya clamp function

Product Features

Strong driving capability, providing 5A/5A source/sink peak current

Integrated Maitreya clamping function, with clamping current up to 5A, effectively suppressing the tube from being mistakenly turned on due to Maitreya effect, ensuring the reliability of the system

Ultra -high common mode immunity: 150 kV/us

 The maximum power supply voltage VCC2 on the driver side is 32V, and the input side VCC1 is powered by a power supply voltage of 3.1V to 17V; both VCC1 and VCC2 have undervoltage protection (UVLO)

RoHS compliant package types: SOP8, SOW8

Working temperature: -40℃ ~ 125℃

RoHS compliant package type: SOW16

Functional Block Diagram

NSi6601M: Effective solution to high dv/dt in high voltage and high frequency systems

With the rise of the third-generation semiconductor SiC MOSFET, higher voltage, higher frequency, smaller size, and higher power systems are becoming a new development trend. However, in high voltage and high frequency applications, the system is always prone to burn out the power tubes during operation due to excessive dv/dt. NSi6601M can solve this problem well.

Case details

Take the circuit in the figure below as an example. When the system is switching, the dv/dt generated by SW passes through the Maitreya capacitor Cgd, which will cause the gate to generate a voltage. If this voltage is higher than the turn-on voltage of the tube, it will cause the tube to be turned on by mistake, causing a short circuit between the upper and lower tubes and burning the tube.

NSi66001MC integrates the Maitreya clamp function. NSi6601M can detect the change of gate voltage. When the voltage generated by the gate is 2V, the internal Maitreya clamp function of NSi6601M will be turned on, and the current generated by dv/dt through Cgd will be released to VEE through the minimum impedance path. When the gate voltage is clamped to a sufficiently low voltage, the lower tube Q2 will not be turned on by mistake.

Simplified Application Circuit Diagram

NSi6601M has high isolation withstand voltage, and the wide-body SOW8 package has a Vpk of up to 2121V. At the same time, the CMTI anti-interference capability exceeds 150kv/us. It is very suitable for high-frequency, high-voltage, and high-reliability application scenarios, and is in line with the development trend of the power supply industry.

Free Sample

NSi66x1A/NSi6601M series products are available for samples. If you need to apply for samples or place an order, please email sales@novosns.com or call 0512-62601802.