Question We are using 2 x ADUM6132 to drive a complete bridge , and we observe a heating of both ADUM6132 (even without switching). In the data sheet, only the maximum Quiescent current (280mA) is specified, and not the typical one... It is not easy to measure the quiescent current on my board, but it seems to be around 200mA per IC, which seems a lot!! If it is correct, it means 1W per IC and with a thermal resistor of 45°/W, a heating of +45°C!! Answer Overheating can be an issue with applications of the ADuM6132, especially at no load conditions. The ADuM6132 can consume over 200mA at no load. The output voltage is not regulated and at no load the output needs to be protected from exceeding the 18V maximum rating, so there is an internal circuit which will clamp the output voltage which will cause an internal load that need to be dissipated in the ADuM6132. At no load the internal power can be 1W and can cause a temperature rise of 45C. The temperature could rise even more if provisions are not taken in the layout to help remove heat within the ADuM6132. Page 12 of the datasheet states that enlarged pads should be added with multiple vias from the ground pins to the ground planes to help remove heat from the ADuM6132.

ADuM6132 to drive 1200V IGBT

Question We plan to use ADUM6132 to drive a full bridge configuration which has a HVbus of 560VDC and we have 1200V 50A IGBTs to drive. Are these drivers suitable for 1200V blocking voltage? Answer Sorry, the ADuM6132 is rated per datasheet table 12 for at most 800V peak for Unipolar or DC at 15 year lifetime, not for 1200V. The ADuM5230 can only do 600V, so we don’t have an isoPower gate driver to match the 1200V working voltage.

ADuM6132 Power Consumption

Question We are designing switched mode power supply units for the industry. We are using the ADuM6132ARWZ because of its ideal fitting in our design in terms of functionality. However we have to complain the extraordinary inherent power consumption of this device of typically 200mA respectively 1,25 W at 5V supply, or max. rated at 280mA or 1,4W according to its data sheet. This unusual behaviour forces us to glue an unforeseen extra heat sink (aluminium or ceramic) directly upon the device, which makes the manufacturing process unhandy and unprofessional. Also the recommendation to apply extra copper pads would not be very economic because this implies to vaste extra space of the pcb. Recently, we have realized that a similar device ADuM 3223/4223 having 2 separate coupled drivers only requires less than 10mA, which is considered as normal, and is less than a factor of 25 times less than the internal consumption of the ADuM 6132. And idea what we could do rather than using the existing solution is highly appreciated. Answer The ADuM6132 was made to a specific customer’s requirements. It does consume a lot of power. You can also consider the ADuM5230 as an alternative. The power can be controlled by setting the PWM duty factor externally so it does not get as hot. The ADuM5230 is also getting popular in automotive applications. The ADuM3223/4223 do not contain isoPower so they have much lower power consumption, but power must be supplied from somewhere. We have several alternative methods for doing the power job, including the ADuM3070 which can make high output voltages and is much more efficient.

ADUM6132 and capacitive loading of 10nF effect on the device - Documents - Interface and Isolation

ADUM6132 and capacitive loading of 10nF effect on the device

Question

What will happen when driving loads of 10nF with ADUM6132? The application does not require very high speeds,but of course the driver should not break down.
Would a 10nF load cause issues or deteriorates the driver

Answer

I am afraid we don’t have any plots in the nF range. The output would rise very slowly, in about 2us with a 10nF load. If the frequency were slow inthe kHz range the part should not get too hot, which is important since the ADuM6132 already needs to power the isoPower output.

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ADUM6132 and capacitive loading of 10nF effect on the device