- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄373097 > KA555 (FAIRCHILD SEMICONDUCTOR CORP) single timer PDF資料下載
參數(shù)資料
| 型號(hào)： | KA555 |
| 廠商： | FAIRCHILD SEMICONDUCTOR CORP |
| 元件分類： | 運(yùn)動(dòng)控制電子 |
| 英文描述： | single timer |
| 中文描述： | PULSE; RECTANGULAR, TIMER, PDIP8 |
| 封裝： | DIP-8 |
| 文件頁(yè)數(shù)： | 5/14頁(yè) |
| 文件大?。?/td> | 148K |
| 代理商： | KA555 |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)當(dāng)前第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)
KA555
5
Figure 1 illustrates a monos table circuit. In this mode, the timer generates a fixed pulse whenever the trigger voltage falls
below Vcc/3. When the trigger pulse voltage applied to the #2 pin falls below Vcc/3 while the timer output is low, the timer's
internal flip-flop turns the discharging Tr. off and causes the timer output to become high by charging the external capacitor
C1and setting the flip-flop output at the same time.
The voltage across the external capacitor C1, V
C1
increases exponentially with the time constant t=R
A
*C and reaches 2Vcc/3
at td=1.1R
A
*C. Hence, capacitor C1 is charged through resistor R
A
. The greater the time constant R
A
C, the longer it takes
for the V
C1
to reach 2Vcc/3. In other words, the time constant R
A
C controls the output pulse width.
When the applied voltage to the capacitor C1 reaches 2Vcc/3, the comparator on the trigger terminal resets the flip-flop,
turning the discharging Tr. on. At this time, C1 begins to discharge and the timer output converts to low.
In this way, the timer operating in monos table repeats the above process. Figure 2 shows the time constant relationship based
on R
A
and C. Figure 3 shows the general waveforms during monos table operation.
It must be noted that, for normal operation, the trigger pulse voltage needs to maintain a minimum of Vcc/3 before the timer
output turns low. That is, although the output remains unaffected even if a different trigger pulse is applied while the output is
high, it may be affected and the waveform not operate properly if the trigger pulse voltage at the end of the output pulse
remains at below Vcc/3. Figure 4 shows such timer output abnormality
.
2. Astable Operation
Figure 4. Waveforms of Monos table Operation (abnormal)
100m
1
10
100
1k
10k
100k
1E-3
0.01
0.1
1
10
100
1M
1M
10k
1k
1k
(R
A
+2R
B
)
C
Frequency(Hz)
Figure 5. Astable Circuit
Figure 6. Capacitance and Resistance vs. Frequency
1
5
6
7
8
4
2
3
RESET
Vcc
DISCH
THRES
CONT
GND
OUT
TRIG
+Vcc
R
A
C1
C2
R
L
R
B
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| KA558 | Tantalum Molded High Reliability Capacitor; Capacitance: 68uF; Voltage: 6.3V; Case Size: 7.3x4.3 mm; Packaging: Tape & Reel |
| KA558B | Tantalum Molded High Reliability Capacitor; Capacitance: 15uF; Voltage: 10V; Case Size: 6x3.2 mm; Packaging: Tape & Reel |
| KA558BD | Quad Timer |
| KA558D2 | Quad Timer |
| KA5H0165R | Fairchild Power Switch(FPS) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| KA555 | 制造商:Fairchild Semiconductor Corporation 功能描述:IC TIMER 555 DIP8 |
| KA555_Q | 功能描述:計(jì)時(shí)器和支持產(chǎn)品 Single Timer RoHS:否 制造商:Micrel 類型:Standard 封裝 / 箱體:SOT-23 內(nèi)部定時(shí)器數(shù)量:1 電源電壓-最大:18 V 電源電壓-最小:2.7 V 最大功率耗散: 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝:Reel |
| KA555D | 功能描述:計(jì)時(shí)器和支持產(chǎn)品 Single RoHS:否 制造商:Micrel 類型:Standard 封裝 / 箱體:SOT-23 內(nèi)部定時(shí)器數(shù)量:1 電源電壓-最大:18 V 電源電壓-最小:2.7 V 最大功率耗散: 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝:Reel |
| KA555D | 制造商:Fairchild Semiconductor Corporation 功能描述:IC TIMER SMD SOIC8 555 |
| KA555DTF | 功能描述:計(jì)時(shí)器和支持產(chǎn)品 Single Timer RoHS:否 制造商:Micrel 類型:Standard 封裝 / 箱體:SOT-23 內(nèi)部定時(shí)器數(shù)量:1 電源電壓-最大:18 V 電源電壓-最小:2.7 V 最大功率耗散: 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝:Reel |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。