- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384736 > MIC3775-1.5BMM (MICREL INC) 750mA UCap Low-Voltage Low-Dropout Regulator PDF資料下載
參數(shù)資料
| 型號： | MIC3775-1.5BMM |
| 廠商： | MICREL INC |
| 元件分類： | 基準(zhǔn)電壓源/電流源 |
| 英文描述： | 750mA UCap Low-Voltage Low-Dropout Regulator |
| 中文描述： | 1.5 V FIXED POSITIVE LDO REGULATOR, 0.5 V DROPOUT, PDSO8 |
| 封裝： | MSOP-8 |
| 文件頁數(shù)： | 10/14頁 |
| 文件大?。?/td> | 139K |
| 代理商： | MIC3775-1.5BMM |
MIC3775
Applications Information
The MIC3775 is a high-performance low-dropout voltage
regulator suitable for moderate to high-current voltage regu-
lator applications. Its 500mV dropout voltage at full load and
overtemperature makes it especially valuable in battery-
powered systems and as high-efficiency noise filters in post-
regulator applications. Unlike older NPN-pass transistor de-
signs, where the minimum dropout voltage is limited by the
base-to-emitter voltage drop and collector-to-emitter satura-
tion voltage, dropout performance of the PNP output of these
devices is limited only by the low V
CE
saturation voltage.
A trade-off for the low-dropout voltage is a varying base drive
requirement. Micrel
’
s Super
β
eta PNP
process reduces
this drive requirement to only 2% of the load current.
The MIC3775 regulator is fully protected from damage due to
fault conditions. Linear current limiting is provided. Output
current during overload conditions is constant. Thermal shut-
down disables the device when the die temperature exceeds
the maximum safe operating temperature. The output struc-
ture of these regulators allows voltages in excess of the
desired output voltage to be applied without reverse current
flow.
Micrel
MIC3775
10
March 2003
MIC3775-x.xBMM
IN
OUT
GND
C
IN
C
OUT
V
IN
V
OUT
Figure 1. Capacitor Requirements
Output Capacitor
The MIC3775 requires an output capacitor for stable opera-
tion. As a
μ
Cap LDO, the MIC3775 can operate with ceramic
output capacitors as long as the amount of capacitance is
10
μ
F or greater. For values of output capacitance lower than
10
μ
F, the recommended ESR range is 200m
to 2
. The
minimum value of output capacitance recommended for the
MIC3775 is 4.7
μ
F.
For 10
μ
F or greater the ESR range recommended is less than
1
. Ultra-low ESR ceramic capacitors are recommended for
output capacitance of 10
μ
F or greater to help improve tran-
sient response and noise reduction at high frequency.
X7R/X5R dielectric-type ceramic capacitors are recom-
mended because of their temperature performance. X7R-
type capacitors change capacitance by 15% over their oper-
ating temperature range and are the most stable type of
ceramic capacitors. Z5U and Y5V dielectric capacitors change
value by as much as 50% and 60% respectively over their
operating temperature ranges. To use a ceramic chip capaci-
tor with Y5V dielectric, the value must be much higher than an
X7R ceramic capacitor to ensure the same minimum capaci-
tance over the equivalent operating temperature range.
Input Capacitor
An input capacitor of 1
μ
F or greater is recommended when
the device is more than 4 inches away from the bulk AC
supply capacitance or when the supply is a battery. Small,
surface mount, ceramic chip capacitors can be used for
bypassing. Larger values will help to improve ripple rejection
by bypassing the input to the regulator, further improving the
integrity of the output voltage.
Error Flag
The MIC3775 features an error flag (FLG), which monitors
the output voltage and signals an error condition when this
voltage drops 5% below its expected value. The error flag is
an open-collector output that pulls low under fault conditions
and may sink up to 10mA. Low output voltage signifies a
number of possible problems, including an overcurrent fault
(the device is in current limit) or low input voltage. The flag
output is inoperative during overtemperature conditions. A
pull-up resistor from FLG to either V
IN
or V
OUT
is required for
proper operation. For information regarding the minimum and
maximum values of pull-up resistance, refer to the graph in
the
“
Typical Characteristics
”
section of the data sheet.
Enable Input
The MIC3775 features an active-high enable input (EN) that
allows on-off control of the regulator. Current drain reduces
to
“
zero
”
when the device is shutdown, with only microam-
peres of leakage current. The EN input has TTL/CMOS
compatible thresholds for simple logic interfacing. EN may be
directly tied to V
IN
and pulled up to the maximum supply
voltage
Transient Response and 3.3V to 2.5V or 2.5V to 1.8V or
1.65V Conversion
The MIC3775 has excellent transient response to variations
in input voltage and load current. The device has been
designed to respond quickly to load current variations and
input voltage variations. Large output capacitors are not
required to obtain this performance. A standard 10
μ
F output
capacitor, is all that is required. Larger values help to improve
performance even further.
By virtue of its low-dropout voltage, this device does not
saturate into dropout as readily as similar NPN-based de-
signs. When converting from 3.3V to 2.5V or 2.5V to 1.8V or
1.65V, the NPN-based regulators are already operating in
dropout, with typical dropout requirements of 1.2V or greater.
To convert down to 2.5V or 1.8V without operating in dropout,
NPN-based regulators require an input voltage of 3.7V at the
very least. The MIC3775 regulator will provide excellent
performance with an input as low as 3.0V or 2.5V respec-
tively. This gives the PNP-based regulators a distinct advan-
tage over older, NPN-based linear regulators.
Minimum Load Current
The MIC3775 regulator is specified between finite loads. If
the output current is too small, leakage currents dominate
and the output voltage rises. A 10mA minimum load current
is necessary for proper regulation.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MIC3775-1.65BMM | 750mA UCap Low-Voltage Low-Dropout Regulator |
| MIC3775-1.8BMM | 750mA UCap Low-Voltage Low-Dropout Regulator |
| MIC3775-2.5BMM | 750mA UCap Low-Voltage Low-Dropout Regulator |
| MIC3775-3.0BMM | 750mA UCap Low-Voltage Low-Dropout Regulator |
| MIC3775-3.3BMM | 750mA UCap Low-Voltage Low-Dropout Regulator |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MIC3775-2.5BMM | 功能描述:IC REG LDO 2.5V .75A 8-MSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性 系列:- 標(biāo)準(zhǔn)包裝:3,000 系列:- 穩(wěn)壓器拓?fù)浣Y(jié)構(gòu):正，固定式 輸出電壓:3.8V 輸入電壓:最高 16V 電壓 - 壓降（標(biāo)準(zhǔn)）:0.3V @ 80mA 穩(wěn)壓器數(shù)量:1 電流 - 輸出:80mA 電流 - 限制（最?。?- 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:SC-74A，SOT-753 供應(yīng)商設(shè)備封裝:SOT-23-5 包裝:帶卷 (TR) 其它名稱:MIC5203-3.8BM5TRMIC5203-3.8BM5TR-ND |
| MIC3775-2.5BMM TR | 功能描述:IC REG LDO 2.5V .75A 8-MSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性 系列:- 標(biāo)準(zhǔn)包裝:3,000 系列:- 穩(wěn)壓器拓?fù)浣Y(jié)構(gòu):正，固定式 輸出電壓:3.8V 輸入電壓:最高 16V 電壓 - 壓降（標(biāo)準(zhǔn)）:0.3V @ 80mA 穩(wěn)壓器數(shù)量:1 電流 - 輸出:80mA 電流 - 限制（最?。?- 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:SC-74A，SOT-753 供應(yīng)商設(shè)備封裝:SOT-23-5 包裝:帶卷 (TR) 其它名稱:MIC5203-3.8BM5TRMIC5203-3.8BM5TR-ND |
| MIC3775-2.5YMM | 功能描述:低壓差穩(wěn)壓器 - LDO 750mA Low Voltage uCap LDO in Power MSOP-8 Pkg(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(fù)載調(diào)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(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| MIC3775-2.5YMM TR | 功能描述:低壓差穩(wěn)壓器 - LDO 750mA Low Voltage uCap LDO in Power MSOP-8 Pkg(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(fù)載調(diào)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(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| MIC3775-2.5YMMTR | 制造商:RF Micro Devices Inc 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。