20/24

TSZ02201-0212ACB00200-1-2

© 2021 ROHM Co., Ltd. All rights reserved.

21.Jan.2022 Rev.001

www.rohm.com

TSZ22111

• 15 • 001

BD62012BFS

Operational Notes

1. Reverse Connection of Power Supply

Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when

connecting the power supply, such as mounting an external diode between the power supply an

d the IC’s power supply

pins.

2. Power Supply Lines

Design the PCB layout pattern to provide low impedance supply lines. Separate the ground and supply lines of the digital

and analog blocks to prevent noise in the ground and supply lines of the digital block from affecting the analog block.

Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of temperature and aging on the

capacitance value when using electrolytic capacitors.

3. Ground Voltage

Ensure that no pins are at a voltage below that of the ground pin at any time, even during transient condition. However, pins

that drive inductive loads (e.g. motor driver outputs, DC-DC converter outputs) may inevitably go below ground due to back

EMF or electromotive force. In such cases, the user should make sure that such voltages going below ground will not cause

the IC and the system to malfunction by examining carefully all relevant factors and conditions such as motor characteristics,

supply voltage, operating frequency and PCB wiring to name a few.

4. Ground Wiring Pattern

When using both small-signal and large-current ground traces, the two ground traces should be routed separately but

connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal ground

caused by large currents. Also ensure that the ground traces of external components do not cause variations on the ground

voltage. The ground lines must be as short and thick as possible to reduce line impedance.

5. Recommended Operating Conditions

The function and operation of the IC are guaranteed within the range specified by the recommended operating conditions.

The characteristic values are guaranteed only under the conditions of each item specified by the electrical characteristics.

6. Inrush Current

When power is first supplied to the IC, it is possible that the internal logic may be unstable and inrush current may flow

instantaneously due to the internal powering sequence and delays, especially if the IC has more than one power supply.

Therefore, give special consideration to power coupling capacitance, power wiring, width of ground wiring, and routing of

connections.

7. Testing on Application Boards

When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may subject the

IC to stress. Always

discharge capacitors completely after each process or step. The IC’s power supply should always be

turned off completely before connecting or removing it from the test setup during the inspection process. To prevent damage

from static discharge, ground the IC during assembly and use similar precautions during transport and storage.

8. Inter-pin Short and Mounting Errors

Ensure that the direction and position are correct when mounting the IC on the PCB. Incorrect mounting may result in

damaging the IC. Avoid nearby pins being shorted to each other especially to ground, power supply and output pin. Inter-pin

shorts could be due to many reasons such as metal particles, water droplets (in very humid environment) and unintentional

solder bridge deposited in between pins during assembly to name a few.

9. Unused Input Pins

Input pins of an IC are often connected to the gate of a MOS transistor. The gate has extremely high impedance and

extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. The small charge

acquired in this way is enough to produce a significant effect on the conduction through the transistor and cause

unexpected operation of the IC. So unless otherwise specified, unused input pins should be connected to the power supply

or ground line.