參數(shù)資料
型號: MIC5211-2.7BM6
廠商: MICREL INC
元件分類: 基準電壓源/電流源
英文描述: Dual レCap 80mA LDO Regulator Preliminary Information
中文描述: DUAL OUTPUT, FIXED POSITIVE LDO REGULATOR, PDSO6
封裝: MO-193C, SOT-23, 6 PIN
文件頁數(shù): 8/12頁
文件大?。?/td> 70K
代理商: MIC5211-2.7BM6
MIC5211
Micrel
MIC5211
8
November 2000
is operating from a 7.2V-nominal two-cell lithium-ion battery
and both regulators are dropping the voltage to 3.0V, then
output current will be limited at higher ambient temperatures.
For example, at 70
°
C ambient the first regulator can supply
3.0V at 50mA output from a 7.2V supply; however, the
second regulator will have limitations on output current to
avoid thermal shutdown. The dissipation of the first regulator
is:
(
+
P
7.2V
3V 50mA
7.2V 0.85mA
D1
=
P
216mW
D1
=
Since maximum power dissipation for the dual regulator is
250mW at 70
°
C, the second regulator can only dissipate up
to 34mW without going into thermal shutdown. The amount
of current the second regulator can supply is:
P
34mW
D2(max)
=
7.2V
3V I
34mW
OUT2(max)
(
)
=
4.2V I
34mW
OUT2(max)
=
I
8mA
OUT2(max)
=
The second regulator can provide up to 8mA output current,
suitable for the keep-alive circuitry often required in hand-
held applications.
Refer to Application Hint 17 for heat sink requirements when
higher power dissipation capability is needed. Refer to De-
signing with Low Dropout Voltage Regulatorsfor a more
thorough discussion of regulator thermal characteristics.
Dual-Voltage Considerations
For configurations where two different voltages are needed in
the system, the MIC5211 has the option of having two
independent output voltages from the same input. For ex-
ample, a 3.3V rail and a 5.0V rail can be supplied from the
MIC5211 for systems that require both voltages. Important
considerations must be taken to ensure proper functionality
of the part. The input voltage must be high enough for the 5V
section to operate correctly, this will ensure the 3.3V section
proper operation as well.
Both regulators live off of the same input voltage, therefore
the amount of output current each regulator supplies may be
limited thermally. The maximum power the MIC5211 can
dissipate at room temperature is 455mW, as shown in the
Thermal Considerations
section. If we assume 6V input
voltage and 50mA of output current for the 3.3V section of the
regulator, then the amount of output current the 5V section
can provide can be calculated based on the power dissipa-
tion.
P
D
= (V
GND
V
OUT
) I
OUT
+ V
GND
·
I
GND
P
D(3.3V)
= (6V
3.3V) 50mA + 6V
·
0.85mA
P
D(3.3V)
= 140.1mW
P
D(max)
= 455mW
P
D(max)
P
D(3.3V)
= P
D(5V)
P
D(5V)
= 455mW
140.1mW
P
D(5V)
= 314.9mW
Based on the power dissipation allowed for the 5V section,
the amount of output current it can source is easily calculated.
P
D(5V)
= 314.9mW
314.9mW = (6V
5V) I
MAX
6V
·
I
GND
(I
GND
typically adds less than 5% to the total power dissipa-
tion and in this case can be ignored)
314.9mW = (6V
5V) I
MAX
I
MAX
= 314.9mA
I
MAX
exceeds the maximum current rating of the device.
Therefore, for this condition, the MIC5211 can supply 50mA
of output current from each section of the regulator.
相關PDF資料
PDF描述
MIC5211-2.8BM6 Dual μCap 80mA LDO Regulator
MIC5211-3.3BM6 Dual レCap 80mA LDO Regulator Preliminary Information
MIC5211-3.6BM6 Dual μCap 80mA LDO Regulator
MIC5211-5.0BM6 Dual μCap 80mA LDO Regulator
MIC5212 Dual 500mA LDO Regulator
相關代理商/技術參數(shù)
參數(shù)描述
MIC5211-3.0BM6 制造商:Rochester Electronics LLC 功能描述:- Bulk
MIC5211-3.0BM6 TR 功能描述:IC REG LDO 3V 50MA SOT23-6 RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性 系列:- 標準包裝:500 系列:- 穩(wěn)壓器拓撲結構:正,固定式 輸出電壓:12V 輸入電壓:14.5 V ~ 35 V 電壓 - 壓降(標準):- 穩(wěn)壓器數(shù)量:1 電流 - 輸出:500mA 電流 - 限制(最?。?- 工作溫度:-40°C ~ 125°C 安裝類型:通孔 封裝/外殼:TO-205AD,TO-39-3 金屬罐 供應商設備封裝:TO-39 包裝:散裝 其它名稱:*LM78M12CH*LM78M12CH/NOPBLM78M12CH
MIC5211-3.0YM6 制造商:MICREL 制造商全稱:Micrel Semiconductor 功能描述:Dual μCap 80mA LDO Regulator
MIC5211-3.0YM6 TR 功能描述:低壓差穩(wěn)壓器 - LDO Dual Cap 50mA LDO (Lead Free) RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓(最大值):307 mV 輸出電流:1 A 負載調節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風格:SMD/SMT 封裝 / 箱體:VQFN-20
MIC5211-3.2BM6 TR 功能描述:IC REG LDO 3.2V 50MA SOT23-6 RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性 系列:- 標準包裝:500 系列:- 穩(wěn)壓器拓撲結構:正,固定式 輸出電壓:12V 輸入電壓:14.5 V ~ 35 V 電壓 - 壓降(標準):- 穩(wěn)壓器數(shù)量:1 電流 - 輸出:500mA 電流 - 限制(最?。?- 工作溫度:-40°C ~ 125°C 安裝類型:通孔 封裝/外殼:TO-205AD,TO-39-3 金屬罐 供應商設備封裝:TO-39 包裝:散裝 其它名稱:*LM78M12CH*LM78M12CH/NOPBLM78M12CH