An estimation " />
參數(shù)資料
型號： DSP56857BUE
廠商： Freescale Semiconductor
文件頁數(shù)： 43/53頁
文件大小： 0K
描述： IC DSP 16BIT 120MHZ 100-LQFP
標準包裝： 90
系列： 568xx
核心處理器： 56800E
芯體尺寸： 16-位
速度： 120MHz
連通性： SCI，SPI，SSI
外圍設備： DMA，POR，WDT
輸入/輸出數(shù)： 47
程序存儲器容量： 80KB（40K x 16）
程序存儲器類型： SRAM
RAM 容量： 24K x 16
電壓 - 電源 (Vcc/Vdd)： 1.62 V ~ 1.98 V
振蕩器型： 外部
工作溫度： -40°C ~ 85°C
封裝/外殼： 100-LQFP
包裝： 托盤
56857 Technical Data, Rev. 6
48
Freescale Semiconductor
Part 6 Design Considerations
6.1 Thermal Design Considerations
An estimation of the chip junction temperature, TJ, in °C can be obtained from the equation:
Equation 1: TJ = TA + (PD x RθJA)
Where:
TA = ambient temperature °C
RθJA = package junction-to-ambient thermal resistance °C/W
PD = power dissipation in package
Historically, thermal resistance has been expressed as the sum of a junction-to-case thermal resistance and
a case-to-ambient thermal resistance:
Equation 2: RθJA = RθJC + RθCA
Where:
RθJA = package junction-to-ambient thermal resistance °C/W
RθJC = package junction-to-case thermal resistance °C/W
RθCA = package case-to-ambient thermal resistance °C/W
RθJC is device-related and cannot be influenced by the user. The user controls the thermal environment to
change the case-to-ambient thermal resistance, RθCA. For example, the user can change the air flow around
the device, add a heat sink, change the mounting arrangement on the Printed Circuit Board (PCB), or
otherwise change the thermal dissipation capability of the area surrounding the device on the PCB. This
model is most useful for ceramic packages with heat sinks; some 90% of the heat flow is dissipated through
the case to the heat sink and out to the ambient environment. For ceramic packages, in situations where
the heat flow is split between a path to the case and an alternate path through the PCB, analysis of the
device thermal performance may need the additional modeling capability of a system level thermal
simulation tool.
The thermal performance of plastic packages is more dependent on the temperature of the PCB to which
the package is mounted. Again, if the estimations obtained from RθJA do not satisfactorily answer whether
the thermal performance is adequate, a system level model may be appropriate.
A complicating factor is the existence of three common definitions for determining the junction-to-case
thermal resistance in plastic packages:
Measure the thermal resistance from the junction to the outside surface of the package (case) closest to the
chip mounting area when that surface has a proper heat sink. This is done to minimize temperature variation
across the surface.
Measure the thermal resistance from the junction to where the leads are attached to the case. This definition
is approximately equal to a junction to board thermal resistance.
Use the value obtained by the equation (TJ – TT)/PD where TT is the temperature of the package case
determined by a thermocouple.
相關PDF資料
PDF描述
DSP56858FVE IC DSP 16BIT 120MHZ 144-LQFP
DSP56F801FA80E IC DSP 60MHZ 16KB FLASH 48-LQFP
DSP56F802TA80E IC DSP 60MHZ 16KB FLASH 32-LQFP
DSP56F803BU80E IC DSP 80MHZ 64KB FLASH 100LQFP
DSP56F805FV80E IC DSP 80MHZ 64KB FLASH 144LQFP
相關代理商/技術參數(shù)
參數(shù)描述
DSP56857E 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:16-bit Digital Signal Controllers
DSP56857PB 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:120 MIPS Hybrid Processor
DSP56858 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:16-bit Digital Signal Controllers
DSP56858E 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:16-bit Digital Signal Controllers
DSP56858EVM 制造商:Freescale Semiconductor 功能描述:Microprocessor Support IC For Use With:D
發(fā)布緊急采購，3分鐘左右您將得到回復。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*