Datasheet
BAxxDD0xx BAxxCC0xx
When using at temperatures over Ta=25℃, please refer to the heat reducing characteristics shown in Fig.29 through 31.
The IC characteristics are closely related to the temperature at which the IC is used and if the temperature exceeds the
maximum junction temperature TjMAX., the elements may be damaged or destroyed. From the standpoints of instantaneous
destruction and long-term operating reliability, it is necessary give sufficient consideration to IC heat. In order to protect the
IC from thermal damage, it is necessary to operate it at temperatures lower than the maximum junction temperature TjMAX
of the IC.
Fig.30 shows the acceptable loss and heat reducing characteristics of the TO220FP package The portion shown by the
diagonal line is the acceptable loss range that can be used with the IC alone. Even when the ambient temperature Ta is a
normal temperature (25℃), the chip (junction) temperature Tj may be quite high so please operate the IC at temperatures
less than the acceptable loss Pd.
Vcc：
Input voltage
The method of calculating the power consumption Pc (W) is as follows.
Vo：
Output voltage
Io：
Load current
Pc = (Vcc-Vo) × Io ＋ Vcc × Icca
Acceptable loss Pd≦Pc
Vcca：
Circuit current
Solving this for load current IO in order to operate within the acceptable loss:
Pd – Vcc×Icca
Io≦
Vcc－Vo
(Please refer to Fig.10 and 22 for Icca.)
It is then possible to find the maximum load current IoMAX with respect to the applied voltage Vcc at the time of thermal design.
・Calculation Example
Example 1) When Ta=85℃, Vcc=8.3V, Vo=3.3V, BA33DD0WT
1.04－8.3×Icca
Io≦
With the IC alone : θja=62.5℃/W → -16mW/℃
25℃=2000mW → 85℃=1040mW
5
Io≦200mA (Icca : 2mA)
Please refer to the above information and keep thermal designs within the scope of acceptable loss for all operating
temperature ranges.
The power consumption Pc of the IC when there is a short circuit (short between Vo and GND) is:
Pc=Vcc×(Icca＋Ishort)
*Ishort: Short circuit current
●Peripheral Circuit Considerations
・Vcc Terminal
Please attach a capacitor (greater than 0.33µF) between the Vcc and GND.
The capacitance values will differ depending on the application, so please take this into account when configuring the terminal.
・GND Terminal
Please be sure to keep the set ground and IC ground at the same potential level so that a potential difference does not
arise between them.
If a potential difference arises between the set ground and the IC ground, the preset voltage will not be outputted,
causing the system to become unstable. Therefore, please reduce the impedance by making the ground patterns as wide
as possible and by reducing the distance between the set ground and the IC ground as much as possible.
・CTL Terminal
The CTL terminal is turned ON at 2.0V and higher and OFF at 0.8V and lower within the operating power supply voltage range.
CC0xx series, the power supply and the CTL terminal in any order without problems.
●Vo Terminal
100
100
10
Unstable operating region
Unstable operating region
10
Stable operating region
OUT
Stable operating region
1
IC
1
22 F
μ
0.1
1
Unstable operating region
Unstable operating region
0.1
0
200
600
800
1000
400
100
10
10000
1000
1
OUTPUT CURRENT：lo(mA)
OUTPUT CURRENT：lo(mA)
Fig.32 Output Equivalent Circuit
Fig.33 ESR-Io Characteristics
(BAxxCC0)
Fig.34 ESR vs. Io Characteristics
(BAxxDD0)
Please attach an anti-oscillation capacitor between Vo and GND. The capacitance of the capacitor may significantly change
due to factors such as temperature changes, making it impossible to completely stop oscillations. Please use a tantalum
capacitor or aluminum electrolysis capacitor with favorable characteristics and small internal series resistance (ESR) even
at low temperatures. The output fluctuates regardless of whether the ESR is large or small. Please use the IC within the
stable operating region while referring to the ESR characteristics reference data shown in Fig.32 through 34. In applications
where there are sudden load fluctuations, the use of a capacitor with large capacitance is recommended.
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TSZ02201-0R6R0A600130-1-2
25.July.2013 Rev.002
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