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(shù)資料
型號(hào): PSD303-A-15J
廠商: 意法半導(dǎo)體
英文描述: Low Cost Field Programmable Microcontroller Peripherals
中文描述: 低成本現(xiàn)場(chǎng)可編程微控制器外圍設(shè)備
文件頁(yè)數(shù): 36/85頁(yè)
文件大小: 691K
代理商: PSD303-A-15J
PSD3XX Famly
33
All the inputs shown, except CSI, go to the PAD logic. These signals must be taken into
consideration when calculating the composite frequency. Before we make the calculation,
let’s establish the following conditions:
The input with the highest frequency is ALE, which is 2 MHz. So our base period is
500 nsec for this example.
Only the address information from the multiplexed signals AD0-AD7 reach the PAD
logic because of the internal address latch. Signal transitions from data on AD0-AD7
do not reach the PADs.
The three inputs (Int, Sel, or Rdy) change state very infrequently relative to the 80C31
bus signals.
Now, lets assume the following is a snapshot in time of all the input signals during a typical
80C31 bus cycle. We’ll use a code fetch as an example since that happens most often.
16.0
Power
Management
(cont.)
ONE TYPICAL 80C31 BUS CYCLE (2 MHz, 500 nsec)
ALE
PSEN
AD0-AD7
A8-A15
INT
SEL
RDY
FOUR DISTINCT
TRANSITIONS
<25 nsec
ADDR
DATA
1
2
3
The calculation of the composite frequency is as follows:
There are four distinct transitions (first four dotted lines) within the base period of
500 nsec. These first four transitions all count toward the final composite frequency.
The transition at (1) in the diagram does not count as a distinct transition because it is
within 25 nsec of a neighboring transition (use 50 nsec for a ZPSD3XXV device).
Transition (2) above does not add to the composite frequency because only the
internally latched address signals reach the PADs, the data signal transitions do not.
The transition at (3) just happens to appear in this snapshot, but its frequency is so
low that it is not a significant contributor to the overall composite frequency, and will
not be used.
Divide the 500 nsec base period by the four (distinct transitions), yielding 125 nsec.
1/125 nsec = 8 MHz.
Use 8 MHz as the composite frequency of PAD inputs when calculating current
consumption. (See the next section for a sample current calculation.)
16.6 Loading on I/Opins
A final consideration when calculating the current usage for the entire PSD device is the
loading on I/O pins. All specifications for PSD current consumption in this document
assume zero current flowing through PSD I/O pins (including ADIO). I/O current is dictated
by the individual design implementation, and must be calculated by the designer. Be aware
that I/O current is a function of loading on the pins and the frequency at which the signals
toggle.
相關(guān)PDF資料
PDF描述
PSD303-A-15JI Low Cost Field Programmable Microcontroller Peripherals
PSD303-A-15JM Low Cost Field Programmable Microcontroller Peripherals
PSD303-A-20J Low Cost Field Programmable Microcontroller Peripherals
PSD303-A-20JI Low Cost Field Programmable Microcontroller Peripherals
PSD303-A-20JM Low Cost Field Programmable Microcontroller Peripherals
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PSD303-A-15JI 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Low Cost Field Programmable Microcontroller Peripherals
PSD303-A-15JM 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Low Cost Field Programmable Microcontroller Peripherals
PSD303-A-20J 制造商:WSI 功能描述:
PSD303-A-20JI 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Low Cost Field Programmable Microcontroller Peripherals
PSD303-A-20JM 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Low Cost Field Programmable Microcontroller Peripherals
主站蜘蛛池模板: 德庆县| 古田县| 乌海市| 宜昌市| 陆河县| 二手房| 岗巴县| 石阡县| 林甸县| 长乐市| 庆城县| 新闻| 天等县| 马关县| 商都县| 富锦市| 洪江市| 孝昌县| 上饶县| 武城县| 元朗区| 安乡县| 巍山| 东兰县| 卢龙县| 晴隆县| 建平县| 清涧县| 上犹县| 临邑县| 白沙| 宣化县| 宁德市| 隆回县| 旬阳县| 封开县| 汤原县| 交口县| 广河县| 云安县| 巴楚县|