欧美成人免费电影,国产欧美一区二区三区精品酒店,精品国产a毛片,色网在线免费观看

參數資料
型號: THS4227PWP
廠商: TEXAS INSTRUMENTS INC
元件分類: 音頻/視頻放大
英文描述: 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO16
封裝: POWERPAD, PLASTIC, TSSOP-16
文件頁數: 13/32頁
文件大?。?/td> 411K
代理商: THS4227PWP
THS4221, THS4225
THS4222, THS4226
THS4223, THS4227
SLOS399C – AUGUST 2002 – REVISED JANUARY 2003
www.ti.com
20
Figure 37. PowerPAD PCB Etch and Via
Pattern
Single or Dual
68 Mils x 70 Mils
(Via diameter = 13mils)
PowerPAD PCB LAYOUT CONSIDERATIONS
1.
Prepare the PCB with a top side etch pattern as shown
in Figure 37. There should be etch for the leads as well
as etch for the thermal pad.
2.
Place five holes in the area of the thermal pad. These
holes should be 13 mils in diameter. Keep them small
so that solder wicking through the holes is not a
problem during reflow.
3.
Additional vias may be placed anywhere along the
thermal plane outside of the thermal pad area. They
help dissipate the heat generated by the THS4222
family IC. These additional vias may be larger than the
13-mil diameter vias directly under the thermal pad.
They can be larger because they are not in the thermal
pad area to be soldered, so that wicking is not a
problem.
4.
Connect all holes to the internal ground plane.
5.
When connecting these holes to the ground plane, do
not use the typical web or spoke via connection
methodology. Web connections have a high thermal
resistance connection that is useful for slowing the
heat transfer during soldering operations. This
resistance makes the soldering of vias that have plane
connections easier. In this application, however, low
thermal resistance is desired for the most efficient
heattransfer. Therefore, the holes under the THS4222
family PowerPAD package should make their
connection to the internal ground plane, with a
complete connection around the entire circumference
of the plated-through hole.
6.
The top-side solder mask should leave the terminals
of the package and the thermal pad area with its five
holes exposed. The bottom-side solder mask should
cover the five holes of the thermal pad area. This
prevents solder from being pulled away from the
thermal pad area during the reflow process.
7.
Apply solder paste to the exposed thermal pad area
and all of the IC terminals.
8.
With these preparatory steps in place, the IC is simply
placed in position and run through the solder reflow
operation
as
any
standard
surface-mount
component. This results in a part that is properly
installed.
For a given
θJA , the maximum power dissipation is shown
in Figure 38 and is calculated by the equation 5:
P
D +
Tmax
* T
A
q
JA
where:
PD = Maximum power dissipation of THS4222 (watts)
TMAX = Absolute maximum junction temperature (150°C)
TA = Free-ambient temperature (°C)
θJA = θJC + θCA
θJC = Thermal coefficient from junction to the case
θCA = Thermal coefficient from the case to ambient air
(
°C/W).
The next consideration is the package constraints. The
two sources of heat within an amplifier are quiescent
power and output power. The designer should never forget
about the quiescent heat generated within the device,
especially multi-amplifier devices. Because these devices
have linear output stages (Class AB), most of the heat
dissipation is at low output voltages with high output
currents.
The other key factor when dealing with power dissipation
is how the devices are mounted on the PCB. The
PowerPAD devices are extremely useful for heat
dissipation. But, the device should always be soldered to
a copper plane to fully use the heat dissipation properties
of the PowerPAD. The SOIC package, on the other hand,
is highly dependent on how it is mounted on the PCB. As
more trace and copper area is placed around the device,
θJA decreases and the heat dissipation capability
increases. For a single package, the sum of the RMS
output currents and voltages should be used to choose the
proper package.
THERMAL ANALYSIS
The THS4222 family of devices does not incorporate
automatic thermal shutoff protection, so the designer must
take care to ensure that the design does not violate the
absolute maximum junction temperature of the device.
Failure may result if the absolute maximum junction
temperature of 150
_ C is exceeded.
The thermal characteristics of the device are dictated by
the package and the PC board. Maximum power
dissipation for a given package can be calculated using the
following formula.
(3)
相關PDF資料
PDF描述
THS4227DR 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO16
THS4227D 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO16
THS4225DGNRG4 1 CHANNEL, VIDEO PREAMPLIFIER, PDSO8
THS4221DGNRG4 1 CHANNEL, VIDEO PREAMPLIFIER, PDSO8
THS4226DGQRG4 1 CHANNEL, VIDEO PREAMPLIFIER, PDSO10
相關代理商/技術參數
參數描述
THS4271 制造商:TI 制造商全稱:Texas Instruments 功能描述:LOW NOISE, HIGH SLEW RATE, UNITY GAIN STABLE VOLTAGE FREEBACK AMPLIFIER
THS4271D 功能描述:高速運算放大器 Super-Fast Ultra-Low Distortion RoHS:否 制造商:Texas Instruments 通道數量:1 電壓增益 dB:116 dB 輸入補償電壓:0.5 mV 轉換速度:55 V/us 工作電源電壓:36 V 電源電流:7.5 mA 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube
THS4271D 制造商:Texas Instruments 功能描述:OP AMP HIGH SPEED VFB 4271 SOIC8
THS4271DG4 功能描述:高速運算放大器 Super-Fast Ultra-Low Distortion RoHS:否 制造商:Texas Instruments 通道數量:1 電壓增益 dB:116 dB 輸入補償電壓:0.5 mV 轉換速度:55 V/us 工作電源電壓:36 V 電源電流:7.5 mA 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube
THS4271DGK 功能描述:高速運算放大器 Super-Fast Ultra-Low Distortion RoHS:否 制造商:Texas Instruments 通道數量:1 電壓增益 dB:116 dB 輸入補償電壓:0.5 mV 轉換速度:55 V/us 工作電源電壓:36 V 電源電流:7.5 mA 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube
主站蜘蛛池模板: 安图县| 双鸭山市| 休宁县| 剑河县| 越西县| 郁南县| 多伦县| 都昌县| 虞城县| 抚宁县| 昂仁县| 蓝山县| 永靖县| 略阳县| 黄平县| 六枝特区| 法库县| 龙陵县| 宜章县| 霍林郭勒市| 墨脱县| 中宁县| 额敏县| 遂川县| 晋江市| 涞源县| 博爱县| 启东市| 湘潭市| 天祝| 宁化县| 古丈县| 县级市| 银川市| 柳河县| 英吉沙县| 东乌珠穆沁旗| 临澧县| 彭泽县| 天峨县| 绥棱县|