- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄374715 > SC1456XIMSTRT (Semtech Corporation) Dual 150mA Ultra Low Dropout, Low Noise Regulator PDF資料下載
參數(shù)資料
| 型號(hào)： | SC1456XIMSTRT |
| 廠商： | Semtech Corporation |
| 英文描述： | Dual 150mA Ultra Low Dropout, Low Noise Regulator |
| 中文描述： | 雙150mA的超低壓差，低噪聲穩(wěn)壓器 |
| 文件頁數(shù)： | 9/10頁 |
| 文件大?。?/td> | 202K |
| 代理商： | SC1456XIMSTRT |
9
2005 Semtech Corp.
www.semtech.com
SC1456
POWER MANAGEMENT
Applications Information (Cont.)
Thermal Considerations
The worst-case power dissipation for this part is given
by:
(
+
)
(
V
)
)
MAX
(
2
Q
)
MAX
(
2
IN
)
MAX
(
2
OUT
I
)
MIN
(
2
OUT
)
MAX
(
2
IN
)
MAX
(
Q
)
MAX
(
IN
)
MAX
(
OUT
I
)
MIN
(
OUT
V
)
MAX
(
IN
V
)
MAX
(
D
I
I
V
V
V
P
+
+
=
For all practical purposes, it can be reduced to:
(
+
)
(
)
)
MAX
(
2
OUT
I
)
MIN
(
2
OUT
)
MAX
(
2
IN
)
MAX
(
OUT
I
)
MIN
(
OUT
V
)
MAX
(
V
IN
)
MAX
(
D
V
V
P
=
Looking at a typical application:
V
IN1(MAX)
= V
IN2(MAX)
= 4.2V
V
OUT1(MIN)
= V
= (2.8V - 3.5%) = 2.702V worst-case
I
OUT1
OUT2
= 100mA
T
A
This gives us:
(
2
)
mW
300
100
.
702
.
2
P
)
MAX
(
D
=
=
Using this figure, we can calculate the maximum thermal
impedance allowable to maintain T
J
≤
125°C:
(
)
(
=
)
W
/
C
133
300
.
85
125
P
T
T
)
MAX
(
D
)
MAX
(
A
)
MAX
(
)
MAX
)(
A
J
(
°
=
=
θ
With the standard MSOP-10 Land Pattern shown at the
end of this datasheet, and minimum trace widths, the
thermal impedance junction to ambient for SC1456 is
113°C/W. Thus with no additional heatsinking,
T
J(MAX)
= 119°C.
The junction temperature can be reduced further by the
use of larger trace widths, and connecting pcb copper
area to the GND pins (pins 2 and 7), which connect
directly to the device substrate. Lower junction
temperatures improve overall output voltage accuracy.
Layout Considerations
While layout for linear devices is generally not as critical
as for a switching application, careful attention to detail
will ensure reliable operation.
1) Attaching the part to a larger copper footprint will
enable better heat transfer from the device, especially
on PCBs where there are internal ground and power
planes.
2) Place the input and output capacitors close to the
device for optimal transient response and device
behavior.
3) Connect all ground connections directly to the ground
plane. If there is no ground plane, connect to a common
local ground point before connecting to board ground.
VOUT1 (SEE EQUATION)
VOUT2 = PRESET
VIN1
VIN2
U1
SC1456
1
2
3
4
5
6
7
8
9
10
EN1
GND
SET1
OUT2
IN2
EN2
GND
SET2
OUT1
IN1
C1
1uF
C3
2.2uF
C4
1uF
C2
1uF
R1
R2
(OR VIN1)
Figure 1: Output 1 Set Externally and Output 2 Set Internally
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| SC1456 | Dual 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR |
| SC1456XIMSTR | Dual 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR |
| SC1457 | Cap-Free, NMOS, 150mA Low Dropout Regulator with Reverse Current Protection |
| SC1457EVB | Cap-Free, NMOS, 150mA Low Dropout Regulator with Reverse Current Protection |
| SC1457ISK-X.XTR | Cap-Free, NMOS, 150mA Low Dropout Regulator with Reverse Current Protection |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| SC1457 | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:150mA Ultra Low Dropout Regulator with Undervoltage Flag |
| SC1457EVB | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:150mA Ultra Low Dropout Regulator with Undervoltage Flag |
| SC1457ISK-1.8.TRT | 制造商:Semtech Corporation 功能描述: |
| SC1457ISK1.8TRT | 制造商:Semtech Corporation 功能描述:LDO Regulator Pos 1.8V 0.15A 5-Pin SOT-23 T/R |
| SC1457ISK-X.XTR | 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:150mA Ultra Low Dropout Regulator with Undervoltage Flag |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。