參數(shù)資料
型號: LT1123CST
廠商: LINEAR TECHNOLOGY CORP
元件分類: 基準(zhǔn)電壓源/電流源
英文描述: Cap-Free, NMOS, 150mA Low Dropout Regulator with Reverse Current Protection
中文描述: 5 V FIXED POSITIVE LDO REGULATOR, 0.75 V DROPOUT, PDSO4
封裝: PLASTIC, SOT-223, 4 PIN
文件頁數(shù): 7/16頁
文件大?。?/td> 167K
代理商: LT1123CST
7
LT1123
1123fb
The following assumptions were made in calculating the
data for the curves. Resistors are 5% tolerance and the
values shown on the curve are nominal.
For 20mA drive current assume:
V
BE
= 0.95V at I
C
= 1A
V
DRIVE
= 1.75V
For 50mA drive current assume:
V
BE
= 1.2V at I
C
= 2A
V
DRIVE
= 1.9V
For 120mA drive current assume:
V
BE
= 1.4V at I
C
= 4A
V
DRIVE
= 2.1V
The R
D
Selection Chart lists the recommended values for
R
D
for the most useful range of input voltage and output
current. The chart includes a number for power dissipa-
tion for the LT1123 and R
D
.
Current Limit
For regulator circuits using the LT1123, current limiting is
achieved by limiting the base drive to the external PNP
pass transistor. This means that the actual system current
limit will be a function of both the current limit of the
LT1123 and the Beta of the external PNP. Beta-based
current limit schemes are normally not practical because
of uncertainties in the Beta of the pass transistor. Here the
drive characteristics of the LT1123 combined with the
Beta characteristics of the MJE1123 can provide reliable
Beta-based current limiting. This is shown in Figure 5
where the current limit of 30 randomly selected transis-
tors is plotted. The spread of current limit is reasonably
well controlled.
5.5V
R
D
Power (LT1123)
Power (R
D
)
R
D
Power (LT1123)
Power (R
D
)
R
D
Power (LT1123)
Power (R
D
)
R
D
Power (LT1123)
Power (R
D
)
R
D
Power (LT1123)
Power (R
D
)
R
D
Power (LT1123)
Power (R
D
)
120
0.05W
0.12W
150
0.05W
0.13W
180
0.06W
0.16W
240
0.06W
0.17W
270
0.20W
0.07W
330
0.22W
0.07W
43
0.14W
0.32W
51
0.15W
0.35W
75
0.14W
0.36W
91
0.15W
0.42W
110
0.16W
0.47W
130
0.17W
0.52W
––
––
––
20
0.37W
0.76W
27
0.38W
0.89W
36
0.38W
0.97W
43
0.41W
1.11W
51
0.43W
1.25W
6.0V
7.0V
8.0V
9.0V
10.0V
INPUT
VOLTAGE
0A to 4A
0.75V
OUTPUT CURRENT:
DROPOUT VOLTAGE:
0A to 1A
0.3V
0A to 2A
0.4V
R
D
Selection Chart
Note that in some conditions R
D
may be replaced with a
short. This is possible in circuits where an overload is
unlikely and the input voltage and drive requirements are
low. See the section on Thermal Considerations for more
information.
Figure 6. MJE1123 I
C
vs I
B
Figure 5. Short-Circuit Current for 30 Random Devices
OUTPUT CURRENT (A)
4.00
N
3
2
1
0
4
5
4.75
5.25
6.00
LT1123 F05
4.25 4.50
5.00
5.50 5.75
6
7
8
9
10
11
12
13
14
15
I
B
(A)
0
0
I
C
1
3
4
5
0.10
9
LT1123 F06
2
0.05
0.15
6
7
8
APPLICATIOU
W
U
U
相關(guān)PDF資料
PDF描述
LT1123CZ Cap-Free, NMOS, 150mA Low Dropout Regulator with Reverse Current Protection
LT1123 Cap-Free, NMOS, 150mA Low Dropout Regulator with Reverse Current Protection
LT1124 Dual Low Noise, High Speed Precision Op Amps(雙路低噪聲,高速精密運算放大器)
LT1125 Quad Low Noise, High Speed Precision Op Amps(四路低噪聲,高速精密運算放大器)
LT1125ACN Dual/Quad Low Noise, High Speed Precision Op Amps
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LT1123CST#PBF 功能描述:IC REG CTRLR SGL 5V SOT223 RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性晶體管驅(qū)動器 系列:- 產(chǎn)品培訓(xùn)模塊:More Information on LDOs 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:正,固定式 輸出數(shù):2 輸出電壓:2.8V,3.3V 電流 - 電源:12mA 輸入電壓:5 V ~ 22 V 工作溫度:0°C ~ 70°C 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:16-SOIC 包裝:帶卷 (TR)
LT1123CST#TR 功能描述:IC REG CTRLR SGL 5V SOT223 RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性晶體管驅(qū)動器 系列:- 產(chǎn)品培訓(xùn)模塊:More Information on LDOs 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:正,固定式 輸出數(shù):2 輸出電壓:2.8V,3.3V 電流 - 電源:12mA 輸入電壓:5 V ~ 22 V 工作溫度:0°C ~ 70°C 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:16-SOIC 包裝:帶卷 (TR)
LT1123CST#TRPBF 功能描述:IC REG CTRLR SGL 5V SOT223 RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性晶體管驅(qū)動器 系列:- 產(chǎn)品培訓(xùn)模塊:More Information on LDOs 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:正,固定式 輸出數(shù):2 輸出電壓:2.8V,3.3V 電流 - 電源:12mA 輸入電壓:5 V ~ 22 V 工作溫度:0°C ~ 70°C 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:16-SOIC 包裝:帶卷 (TR)
LT1123CZ 功能描述:IC REG CTRLR SGL 5V TO-92-3 RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性晶體管驅(qū)動器 系列:- 產(chǎn)品培訓(xùn)模塊:More Information on LDOs 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:正,固定式 輸出數(shù):2 輸出電壓:2.8V,3.3V 電流 - 電源:12mA 輸入電壓:5 V ~ 22 V 工作溫度:0°C ~ 70°C 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:16-SOIC 包裝:帶卷 (TR)
LT1123CZ#PBF 功能描述:IC REG CTRLR SGL 5V TO-92-3 RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 線性晶體管驅(qū)動器 系列:- 產(chǎn)品培訓(xùn)模塊:More Information on LDOs 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:正,固定式 輸出數(shù):2 輸出電壓:2.8V,3.3V 電流 - 電源:12mA 輸入電壓:5 V ~ 22 V 工作溫度:0°C ~ 70°C 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:16-SOIC 包裝:帶卷 (TR)