- 您现在的位置：买卖IC网 > PDF目录44986 > LT3692EUH#PBF (LINEAR TECHNOLOGY CORP) 5.8 A DUAL SWITCHING CONTROLLER, 2750 kHz SWITCHING FREQ-MAX, PQCC32 PDF资料下载
参数资料
| 型号： | LT3692EUH#PBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 5.8 A DUAL SWITCHING CONTROLLER, 2750 kHz SWITCHING FREQ-MAX, PQCC32 |
| 封装： | 5 X 5 MM, LEAD FREE, PLASTIC, MO-220WHHD, QFN-32 |
| 文件页数： | 18/36页 |
| 文件大小： | 526K |
| 代理商： | LT3692EUH#PBF |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页当前第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页
LT3692
25
3692f
APPLICATIONS INFORMATION
Shorted and Reverse Input Protection
If the inductor is chosen so that it won’t saturate exces-
sively,anLT3692step-downregulatorwilltolerateashorted
output. There is another situation to consider in systems
where the output will be held high when the input to the
LT3692 is absent. This may occur in battery charging
applications or in battery back-up systems where a battery
or some other supply is diode OR-ed with the LT3692’s
output. If the VIN1/2 pin is allowed to float and the SHDN
pin is held high (either by a logic signal or because it is
tied to VIN), then the LT3692’s internal circuitry will pull its
quiescent current through its SW pin. This is fine if your
system can tolerate a few mA in this state. If you ground
the SHDN pin, the SW pin current will drop to essentially
zero. However, if the VIN pin is grounded while the output
is held high, then parasitic diodes inside the LT3692 can
pull large currents from the output through the SW pin
and the VIN1/2 pin. Figure 19 shows a circuit that will run
only when the input voltage is present and that protects
against a shorted or reversed input.
PCB Layout
For proper operation and minimum EMI, care must be
taken during printed circuit board (PCB) layout. Figure 20
shows the high di/dt paths in the buck regulator circuit.
Note that large switched currents flow in the power switch,
the catch diode and the input capacitor. The loop formed
by these components should be as small as possible.
These components, along with the inductor and output
capacitor, should be placed on the same side of the circuit
board and their connections should be made on that layer.
Place a local, unbroken ground plane below these com-
ponents, and tie this ground plane to system ground at
one location, ideally at the ground terminal of the output
capacitor C2. Additionally, the SW and BST traces should
be kept as short as possible.
Thermal Considerations
The PCB must also provide heat sinking to keep the
LT3692 cool. The exposed metal on the bottom of the
package must be soldered to a ground plane. This ground
should be tied to other copper layers below with thermal
vias; these layers will spread the heat dissipated by the
LT3692.Placeadditionalviasnearthecatchdiodes.Adding
more copper to the top and bottom layers and tying this
copper to the internal planes with vias can further reduce
thermal resistance. With these steps, the thermal resis-
tance from die (or junction) to ambient can be reduced to
θJA = 35°C/W.
Figure 19. Diode D4 Prevents a Shorted Input from Discharging a
Backup Battery Tied to the Output
Figure 20. Subtracting the Current when the Switch is On (20a) from the Current when the Switch is Off (20b) Reveals the Path of the
High Frequency Switching Current (20c). Keep this Loop Small. The Voltage on the SW and BST Traces will Also Be Switched; Keep
These Traces as Short as Possible. Finally, Make Sure the Circuit is Shielded with a Local Ground Plane
VIN
GND
(20a)
LT3692 SW
VIN
GND
(20c)
LT3692 SW
3692 F20
VIN
GND
(20b)
LT3692 SW
VIN
VIN1/2
VOUT1/2
SW
LT3692
D4
PARASITIC DIODE
3692 F19
相关PDF资料 |
PDF描述 |
|---|---|
| LT3724MPFE#TR | SWITCHING CONTROLLER, 225 kHz SWITCHING FREQ-MAX, PDSO16 |
| LT3740EDHC | 0.14 A SWITCHING CONTROLLER, 330 kHz SWITCHING FREQ-MAX, PDSO16 |
| LT3741EFE#PBF | SWITCHING CONTROLLER, 1070 kHz SWITCHING FREQ-MAX, PDSO20 |
| LT3741IFE#TRPBF | SWITCHING CONTROLLER, 1070 kHz SWITCHING FREQ-MAX, PDSO20 |
| LT3741EUF#PBF | SWITCHING CONTROLLER, 1070 kHz SWITCHING FREQ-MAX, PQCC20 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT3692IUH#PBF | 功能描述:IC REG BUCK ADJ 3.5A DL 32QFN RoHS:是 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 |
| LT3692IUH#TRPBF | 功能描述:IC REG BUCK ADJ 3.5A DL 32QFN RoHS:是 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 |
| LT3692IUHPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:Monolithic Dual Tracking 3.5A Step-Down Switching Regulator |
| LT3693 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Monolithic Dual Tracking |
| LT36931DD#PBF | 制造商:Linear Technology 功能描述: |
发布紧急采购，3分钟左右您将得到回复。