LV8121V Datasheet, PDF (13/14 Pages) Sanyo Semicon Device – For Fan Motor 3-phase Brushless Motor Driver

LV8121V
12. Low-voltage Shutdown Protection Circuit
The IC includes a low-voltage shutdown protection circuit to protect against incorrect operation when the VCC power
supply is switched on or if the VCC voltage falls below the allowable operating range. When the VCC voltage falls
below the specified voltage (VSDL), this protection function operates, and all the outputs (the both upper side and
lower side N-channel power FET) are turned off. When the VCC voltage rises above the release voltage (VSDH), this
protection function is released.
13. Thermal Shutdown Protection Circuit
If the junction temperature rises to the specified temperature (TSD), this protection function operates, and the upper
side N-channel power FET is turned off. If the temperature decrease falls to more than the hysteresis width (ΔTSD),
this protection function is released.
14. Power Supply Stabilization
Because a large switching current flows in the VCC line, the line inductance and other factors can lead to VCC
voltage fluctuations. Sufficient capacitance should be provided between VCC and GND for stabilization. When long
wiring routes are used, choose a capacitor with even larger capacitance.
Ceramic capacitors of about 0.2μF must be connected between the VCC1 pin and the GND1 pin as close as possible to
these pins for excluding noise.
15. VREG Pin
The VREG pin is the power supply for the control circuits. Therefore, a capacitor of about 0.1μF must be connected
between the VREG pin and the GND1 pin as close as possible to these pins for stabilization.
16. VG Pin
When the S/S pin is the stop mode, the VG pin is the high-impedance condition in the IC. If the ambient temperature
of the capacitor inserted between VG and VCC2 becomes high when the VG pin is the high-impedance condition,
since the voltage charged in this capacitor may rise due to the temperature characteristic of the capacitor, the VG
voltage may rise. Therefore, prevent the VG voltage from rising by inserting the resistor of about 200kΩ between VG
and VCC2 or VG and GND1 so that the VG pin is not the high-impedance condition.
17. Notes on wiring of a Printed Circuit Board
Two pins are provided for each of pins (VCC2, RF, OUT1, OUT2, OUT3, GND2) where large current flows. Both of
these pins should be externally connected.
18. The Metal of the IC’s Backside
The metal of the IC’s backside is the Exposed Die-pad and is internally connected to GND1, GND2. For stabilization,
connect the Exposed Die-pad to GND1 externally. The IC’s generation of heat can be efficiently diffused to a printed
circuit board by soldering the Exposed Die-pad to the copper of the printed circuit board.
19. NC Pins
The NC pins are electrically open. These pins may be used for wiring routes.
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