參數資料
型號: LM139JAN
廠商: National Semiconductor Corporation
英文描述: Low Power Low Offset Voltage Quad Comparators
中文描述: 低功耗低失調電壓四比較
文件頁數: 9/20頁
文件大?。?/td> 772K
代理商: LM139JAN
Application Hints
The LM139 is a high gain, wide bandwidth device which, like
most comparators, can easily oscillate if the output lead is
inadvertently allowed to capacitively couple to the inputs via
stray capacitance. This shows up only during the output
voltage transition intervals as the comparator changes
states. Power supply bypassing is not required to solve this
problem. Standard PC board layout is helpful as it reduces
stray input-output coupling. Reducing the input resistors to
<
10 k
reduces the feedback signal levels and finally, adding
even a small amount (1 to 10 mV) of positive feedback
(hysteresis) causes such a rapid transition that oscillations
due to stray feedback are not possible. Simply socketing the
IC and attaching resistors to the pins will cause input-output
oscillations during the small transition intervals unless hys-
teresis is used. If the input signal is a pulse waveform, with
relatively fast rise and fall times, hysteresis is not required.
All pins of any unused comparators should be tied to the
negative supply.
The bias network of the LM139 establishes a drain current
which is independent of the magnitude of the power supply
voltage over the range of from 5 V
DC
to 30 V
DC
.
It is usually unnecessary to use a bypass capacitor across
the power supply line.
The differential input voltage may be larger than V
+
without
damaging the device. Protection should be provided to pre-
vent the input voltages from going negative more than 0.3
V
(at 25C). An input clamp diode can be used as shown
in the applications section.
The output of the LM139 is the uncommitted collector of a
grounded-emitter NPN output transistor. Many collectors can
be tied together to provide an output OR’ing function. An
output pull-up resistor can be connected to any available
power supply voltage within the permitted supply voltage
range and there is no restriction on this voltage due to the
magnitude of the voltage which is applied to the V
+
terminal
of the LM139 package. The output can also be used as a
simple SPST switch to ground (when a pull-up resistor is not
used). The amount of current which the output device can
sink is limited by the drive available (which is independent of
V
+
) and the
β
of this device. When the maximum current limit
is reached (approximately 16 mA), the output transistor will
come out of saturation and the output voltage will rise very
rapidly. The output saturation voltage is limited by the ap-
proximately 60
R
SAT
of the output transistor. The low offset
voltage of the output transistor (1 mV) allows the output to
clamp essentially to ground level for small load currents.
Typical Applications
(V
+
= 5.0 V
DC
)
Basic Comparator
20129503
Driving CMOS
20129504
Driving TTL
20129505
AND Gate
20129508
OR Gate
20129509
L
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相關代理商/技術參數
參數描述
LM139JB 制造商:Texas Instruments 功能描述:Comparator Quad 制造商:Texas Instruments 功能描述:COMPARATOR QUAD 15V/30V 14CDIP - Rail/Tube
LM139N 功能描述:IC COMPARATOR QUAD LP 14-DIP RoHS:是 類別:集成電路 (IC) >> 線性 - 比較器 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:50 系列:- 類型:帶電壓基準 元件數:4 輸出類型:開路漏極 電壓 - 電源,單路/雙路(±):2.5 V ~ 11 V,±1.25 V ~ 5.5 V 電壓 - 輸入偏移(最小值):10mV @ 5V 電流 - 輸入偏壓(最小值):- 電流 - 輸出(標準):0.015mA @ 5V 電流 - 靜態(tài)(最大值):8.5µA CMRR, PSRR(標準):80dB CMRR,80dB PSRR 傳輸延遲(最大):- 磁滯:- 工作溫度:0°C ~ 70°C 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 安裝類型:表面貼裝 包裝:管件 產品目錄頁面:1386 (CN2011-ZH PDF)
LM139-N 制造商:TI 制造商全稱:Texas Instruments 功能描述:The LM139 series consists of four independent precision voltage comparators with an offset voltage specification as low as 2 mV max for all four comparators.
LM139P 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:LOWPOWER QUAD VOLTAGE COMPARATORS
LM139PT 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:LOWPOWER QUAD VOLTAGE COMPARATORS