BD9673EFJ-E2 ROHM Electronics, BD9673EFJ-E2 Datasheet - Page 16

• Manufacturer Part Number: BD9673EFJ-E2
• Description: Specifications: Type: Step-Down (Buck) ; Output Type: Adjustable ; PWM Type: Current Mode ; Synchronous Rectifier: Yes ; Number of Outputs: 1 ; Voltage - Output: 1 V ~ 29.4 V ; Current - Output: 1.5A ; Frequency - Switching: 300kHz ; Voltage - Input:
• Manufacturer: ROHM Electronics

●Notes for use
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BD9673EFJ
© 2012 ROHM Co., Ltd. All rights reserved.
(10) About High-side Nch FET
(11) About over current detection
(1) About Absolute Maximum Rating
(2) About GND Electric Potential
(3) About Heat Design
(4) About short circuit between pins and erroneous mounting
(5) About the operation inside a strong electro-magnetic field
(6) Temperature Protect Circuit (TSD Circuit)
(7) About checking with Set boards
(8) About common impedance
(9) In the application, when the mode where the VCC and each pin electrical potential becomes reversed exists, there is a
When the absolute maximum ratings of application voltage, operating temperature range, etc. was exceeded, there is
possibility of deterioration and destruction. Also, the short Mode or open mode, etc. destruction condition cannot be
assumed. When the special mode where absolute maximum rating is exceeded is assumed, please give consideration
to the physical safety countermeasure for the fuse, etc.
In every state, please make the electric potential of GND Pin into the minimum electrical potential. Also, include the actual
excessive effect, and please do it such that the pins, excluding the GND Pin do not become the voltage below GND.
Consider the Power Dissipation (Pd) in actual state of use, and please make Heat Design with sufficient margin.
When installing to set board, please be mindful of the direction of the IC, phase difference, etc. If it is not installed
correctly, there is a chance that the IC will be destroyed. Also, if a foreign object enters the middle of output, the middle
of output and power supply GND, etc., even for the case where it is shorted, there is a change of destruction.
When using inside a strong electro-magnetic field, there is a possibility of error, so please be careful.
Temperature Protect Circuit (TSD Circuit) is built-in in this IC. As for the Temperature Protect Circuit (TSD Circuit),
because it a circuit that aims to block the IC from insistent careless runs, it is not aimed for protection and guarantee of
IC. Therefore, please do not assume the continuing use after operation of this circuit and the Temperature Protect
Circuit operation.
When doing examination with the set board, during connection of capacitor to the pin that has low impedance, there is
a possibility of stress in the IC, so for every 1 process, please make sure to do electric discharge. As a countermeasure
for static electricity, in the process of assembly, do grounding, and when transporting or storing please be careful. Also,
when doing connection to the jig in the examination process, please make sure to turn off the power supply, then
connect. After that, turn off the power supply then take it off.
For the power supply and the wire of GND, lower the common impedance, then, as much as possible, make the ripple
smaller (as much as possible make the wire thick and short, and lower the ripple from L・C), etc., then and please
consider it sufficiently.
possibility that the internal circuit will become damaged. For example, during cases wherein the condition when charge
was given in the external capacitor, and the VCC was shorted to GND, it is recommended to insert the bypass diode
to the diode of the back current prevention in the VCC series or the middle of each Pin-VCC.
Please use within 2.0A contained ripple current, because the absolute maximum rating of high-side Nch FET is 2.0A.
The detecting current is the current flowing through high-side NchFET. Output current containing ripple current,
therefore the detecting current is the current of the output current containing ripple current
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Technical Note
2012.02 - Rev.C