- 您现在的位置：买卖IC网 > PDF目录377714 > LT1765-2.5 (Linear Technology Corporation) Isolated Flyback Switching Regulator with 9V Output PDF资料下载
参数资料
| 型号： | LT1765-2.5 |
| 厂商： | Linear Technology Corporation |
| 元件分类： | 基准电压源/电流源 |
| 英文描述： | Isolated Flyback Switching Regulator with 9V Output |
| 中文描述： | 隔离反激式开关稳压9V输出 |
| 文件页数： | 12/20页 |
| 文件大小： | 247K |
| 代理商： | LT1765-2.5 |
LT1765/LT1765-1.8/LT1765-2.5/
LT1765-3.3/LT1765-5
12
sn1765 1765fas
maximum rating. A ground plane should always be used
under the switcher circuitry to prevent interplane coupling
and overall noise.
The V
C
and FB components should be kept as far away as
possible from the switch and boost nodes. The LT1765
pinout has been designed to aid in this. The ground for
these components should be separated from the switch
current path. Failure to do so will result in poor stability or
subharmonic like oscillation.
Board layout also has a significant effect on thermal
resistance. The exposed pad or GND pin is a continuous
copper plate that runs under the LT1765 die. This is the
best thermal path for heat out of the package as can be
seen by the low
θ
JC
of the exposed pad package. Reducing
the thermal resistance from Pin 4 or exposed pad onto the
board will reduce die temperature and increase the power
capability of the LT1765. This is achieved by providing as
much copper area as possible around this pin/pad. Also,
having multiple solder filled feedthroughs to a continuous
copper plane under LT1765 will help in reducing thermal
resistance. Ground plane is usually suitable for this pur-
pose. In multilayer PCB designs, placing a ground plane
next to the layer with the LT1765 will reduce thermal
resistance to a minimum.
THERMAL CALCULATIONS
Power dissipation in the LT1765 chip comes from four
sources: switch DC loss, switch AC loss, boost circuit
current, and input quiescent current. The following
formulas show how to calculate each of these losses.
These formulas assume continuous mode operation, so
they should not be used for calculating efficiency at light
load currents.
Switch loss:
P
R
V
V
ns I
V
f
SW
SW OUT
OUT
IN
OUT
IN
=
) (
)
+
(
)(
)( )
2
17
Boost current loss for V
BOOST
= V
OUT
:
2
P
V
I
V
BOOST
OUT
OUT
IN
=
(
)
50
/
Quiescent current loss:
P
V
Q
IN
=
(
)
0 001
.
R
SW
= Switch resistance (
≈
0.13
at hot)
17ns = Equivalent switch current/voltage overlap time
f = Switch frequency
Figure 6. Typical Application and Layout (Topside Only Shown)
BOOST
LT1765-33
V
IN
OUTPUT
3.3V
2.5A
INPUT
15V
1765 F06
C2
0.18
μ
F
C
2.2nF
D1
B220A
C1
4.7
μ
F
CERAMIC
C3
4.7
μ
F
CERAMIC
D2
CMDSH-3
L1
2.7
μ
H
V
SW
FB
SHDN
SYNC
ON
OFF
GND
V
C
APPLICATIOU
W
U
U
GND
KEEP FB AND V
COMPONENTS AND
TRACES AWAY FROM
HIGH FREQUENCY,
HIGH INPUT
COMPONENTS
PLACE FEEDTHROUGHS
UNDER AND AROUND
GROUND PAD FOR
GOOD THERMAL
CONDUCTIVITY
1765 F6a
GND
MINIMIZE D1, C3
LT1765 LOOP
C3
D2
C2
L1
KELVIN
SENSE
V
OUT
D1
C1
VIN
VOUT
C
C
相关PDF资料 |
PDF描述 |
|---|---|
| LT1767-2.5 | Direct mounting on the PCB, Crimping connection, Discrete wire connectors; HRS No: 544-0063-6 00; No. of Positions: 15; Connector Type: Wire; Contact Gender: Male; Contact Spacing (mm): 2; Terminal Pitch (mm): 2; Termination Style: IDC; Current Rating(Amps)(Max.): 1; Contact Mating Area Plating: Tin; Operating Temperature Range (degrees C): -30 to 85; General Description: Housing; Straight; Direct PCB mounting; For AWG#26 |
| LT1767EMS8 | RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS |
| LT1767EMS8-1.8 | RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS |
| LT1767EMS8-2.5 | RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS |
| LT1767EMS8-3.3 | RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT1765-3.3 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Monolithic 3A, 1.25MHz Step-Down Switching Regulator |
| LT1765-5 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Monolithic 3A, 1.25MHz Step-Down Switching Regulator |
| LT1765EFE | 功能描述:IC REG BUCK ADJ 3A 16TSSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 设计资源:Design Support Tool 标准包装:1 系列:- 类型:升压（升压） 输出类型:固定 输出数:1 输出电压:3V 输入电压:0.75 V ~ 2 V PWM 型:- 频率 - 开关:- 电流 - 输出:100mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SOT-23-5 细型，TSOT-23-5 包装:剪切带 (CT) 供应商设备封装:TSOT-23-5 其它名称:AS1323-BTTT-30CT |
| LT1765EFE#PBF | 功能描述:IC REG BUCK ADJ 3A 16TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:250 系列:- 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V 输入电压:2.05 V ~ 6 V PWM 型:电压模式 频率 - 开关:2MHz 电流 - 输出:500mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:6-UFDFN 包装:带卷 (TR) 供应商设备封装:6-SON（1.45x1） 产品目录页面:1032 (CN2011-ZH PDF) 其它名称:296-25628-2 |
| LT1765EFE#TR | 功能描述:IC REG BUCK ADJ 3A 16TSSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 设计资源:Design Support Tool 标准包装:1 系列:- 类型:升压（升压） 输出类型:固定 输出数:1 输出电压:3V 输入电压:0.75 V ~ 2 V PWM 型:- 频率 - 开关:- 电流 - 输出:100mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SOT-23-5 细型，TSOT-23-5 包装:剪切带 (CT) 供应商设备封装:TSOT-23-5 其它名称:AS1323-BTTT-30CT |
发布紧急采购，3分钟左右您将得到回复。