BA□□BC0 Series,BA□□BC0W Series,BA00BC0W Series
Technical Note
7/8
www.rohm.com
2009.04 - Rev.A
2009 ROHM Co., Ltd. All rights reserved.
Notes for use
1. Absolute maximum ratings
An excess in the absolute maximum ratings, such as supply voltage, temperature range of operating conditions, etc., can break
down the devices, thus making impossible to identify breaking mode, such as a short circuit or an open circuit. If any over rated
values will expect to exceed the absolute maximum ratings, consider adding circuit protection devices, such as fuses.
2. GND voltage
The potential of GND pin must be minimum potential in all operating conditions.
3. Thermal design
Use a thermal design that allows for a sufficient margin in light of the power dissipation (Pd) in actual operating conditions.
4. Inter-pin shorts and mounting errors
Use caution when positioning the IC for mounting on printed circuit boards.
The IC may be damaged if there is any connection error or if pins are shorted together.
5. Actions in strong electromagnetic field
Use caution when using the IC in the presence of a strong electromagnetic field as doing so may cause the IC to malfunction.
6. Testing on application boards
When testing the IC on an application board, connecting a capacitor to a pin with low impedance subjects the IC to stress.
Always discharge capacitors after each process or step. Always turn the IC's power supply off before connecting it to or
removing it from a jig or fixture during the inspection process. Ground the IC during assembly steps as an antistatic
measure. Use similar precaution when transporting or storing the IC.
7. Regarding input pin of the IC
This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them isolated.
P-N junctions are formed at the intersection of these P layers with the N layers of other elements, creating a parasitic diode
or transistor. For example, the relation between each potential is as follows:
When GND > Pin A and GND > Pin B, the P-N junction operates as a parasitic diode.
When GND > Pin B, the P-N junction operates as a parasitic transistor.
Parasitic diodes can occur inevitable in the structure of the IC. The operation of parasitic diodes can result in mutual
interference among circuits, operational faults, or physical damage. Accordingly, methods by which parasitic diodes
operate, such as applying a voltage that is lower than the GND (P substrate) voltage to an input pin, should not be used.
8. Ground Wiring Pattern
When using both small signal and large current GND patterns, it is recommended to isolate the two ground patterns,
placing a single ground point at the ground potential of application so that the pattern wiring resistance and voltage
variations caused by large currents do not cause variations in the small signal ground voltage. Be careful not to change the
GND wiring pattern of any external components, either.
9. Thermal shutdown circuit
The IC incorporates a built-in thermal shutdown circuit (TSD circuit). The thermal shutdown circuit (TSD circuit) is designed
only to shut the IC off to prevent thermal runaway. It is not designed to protect the IC or guarantee its operation. Do not continue
to use the IC after operating this circuit or use the IC in an environment where the operation of this circuit is assumed.
10. Overcurrent Protection Circuit
An overcurrent protection circuit is incorporated in order to prevention destruction due to short-time overload currents.
Continued use of the protection circuits should be avoided. Please note that the current increases negatively impact the temperature.
11. Damage to the internal circuit or element may occur when the polarity of the Vcc pin is opposite to that of the other pins in
applications. (I.e. Vcc is shorted with the GND pin while an external capacitor is charged.) Use a maximum capacitance of
1000μF for the output pins. Inserting a diode to prevent back-current flow in series with Vcc or bypass diodes between Vcc
and each pin is recommended.
Fig.23 Bypass Diode
Fig.24 Example of Simple Bipolar IC Architecture
~ ~
GND
P 基板
N
P
N
P+
(端子
A)
抵抗
~ ~
GND
N
P
N
N
P+
(端子
B)
トランジスタ
(NPN)
B
N
E
C
GND
P 基板
寄生素子
Transistor (NPN)
Resistor
(
PIN A)
P substrate
Parasitic elements
(
PIN B)
N
P
N
(PINA)
GND
Parasitic elements
~ ~
GND
(PINB)
B
C
E
Parasitic elements or
transistors
~ ~
VCC
Output pin
Diode for preventing back current flow
Bypass Diode
P substrate
Parasitic elements