參數資料
型號: 74HC221
廠商: NXP Semiconductors N.V.
英文描述: Dual non-retriggerable monostable multivibrator with reset
中文描述: 雙非retriggerable帶復位單穩(wěn)態(tài)觸發(fā)器
文件頁數: 2/15頁
文件大?。?/td> 250K
代理商: 74HC221
December 1990
2
Philips Semiconductors
Product specification
Dual non-retriggerable monostable
multivibrator with reset
74HC/HCT221
FEATURES
Pulse width variance is typically less than
±
5%
Pin-out identical to “123”
Overriding reset terminates output pulse
nB inputs have hysteresis for improved noise immunity
Output capability: standard (except for nR
EXT
/C
EXT
)
I
CC
category: MSI
GENERAL DESCRIPTION
The 74HC/HCT221 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT221 are dual non-retriggerable monostable
multivibrators. Each multivibrator features an active
LOW-going edge input (nA) and an active HIGH-going
edge input (nB), either of which can be used as an enable
input.
Pulse triggering occurs at a particular voltage level and is
not directly related to the transition time of the input pulse.
Schmitt-trigger input circuitry for the nB inputs allow
jitter-free triggering from inputs with slow transition rates,
providing the circuit with excellent noise immunity.
Once triggered, the outputs (nQ, nQ) are independent of
further transitions of nA and nB inputs and are a function
of the timing components. The output pulses can be
terminated by the overriding active LOW reset inputs
(nR
D
). Input pulses may be of any duration relative to the
output pulse.
Pulse width stability is achieved through internal
compensation and is virtually independent of V
CC
and
temperature. In most applications pulse stability will only
be limited by the accuracy of the external timing
components.
The output pulse width is defined by the following
relationship:
t
W
= C
EXT
R
EXT
In
2
t
W
= 0.7C
EXT
R
EXT
Pin assignments for the “221” are identical to those of the
“123” so that the “221” can be substituted for those
products in systems not using the retrigger by merely
changing the value of R
EXT
and/or C
EXT
.
QUICK REFERENCE DATA
GND = 0 V; T
amb
= 25
°
C; t
r
= t
f
= 6 ns
Notes
1.
C
PD
is used to determine the dynamic power dissipation (P
D
in
μ
W):
P
D
= C
PD
×
V
CC2
×
f
i
+ ∑
(C
L
×
V
CC2
×
f
o
)
+
0.33
×
C
EXT
×
V
CC2
×
f
o
+
D
×
28
×
V
CC
where:
f
i
= input frequency in MHz; f
o
= output frequency in MHz
(C
L
×
V
CC2
×
f
o
) = sum of outputs
C
EXT
= timing capacitance in pF; C
L
= output load capacitance in pF
V
CC
= supply voltage in V; D = duty factor in %
For HC the condition is V
I
= GND to V
CC
For HCT the condition is V
I
= GND to V
CC
1.5 V
2.
SYMBOL
PARAMETER
CONDITIONS
TYPICAL
UNIT
HC
HCT
propagation delay
nA, nB, nR
D
to nQ, nQ
nA, nB, nR
D
to nQ, nQ
input capacitance
power dissipation capacitance per package notes 1 and 2
C
L
= 15 pF; V
CC
= 5 V;
R
EXT
= 5 k
; C
EXT
= 0 pF
t
PHL
t
PLH
C
I
C
PD
29
35
3.5
90
32
36
3.5
96
ns
ns
pF
pF
相關PDF資料
PDF描述
74221 Dual non-retriggerable monostable multivibrator with reset
74221 Dual Monostable Multivibrators (with Schmitt Trigger Input)
74221 High Speed CMOS Logic Dual Monostable Multivibrator with Reset
74221 Dual Non-Retriggerable Monostable Multivibrator
74HCT237 3-to-8 line decoder/demultiplexer with address latches(帶地址鎖存的3-8線譯碼器/多路分解器)
相關代理商/技術參數
參數描述
74HC221AM 制造商: 功能描述: 制造商:undefined 功能描述:
74HC221APTOS91 制造商:TOS 功能描述:74HC221N
74HC221D 制造商:NXP Semiconductors 功能描述:DUAL MONOSTABLE MULTIVIBRATOR 制造商:NXP Semiconductors 功能描述:HC Monostable Multivibrator Bulk 制造商:NXP Semiconductors 功能描述:IC 74HC CMOS SMD 74HC221 SOIC16 制造商:NXP Semiconductors 功能描述:IC, 74HC CMOS, SMD, 74HC221, SOIC16 制造商:NXP Semiconductors 功能描述:IC, 74HC CMOS, SMD, 74HC221, SOIC16; Multivibrator Type:Non Retriggerable Monostable; Output Current:5.2mA; Propagation Delay:21ns; Logic Case Style:SOIC; No. of Pins:16; Supply Voltage Min:2V; Supply Voltage Max:6V; Operating ;RoHS Compliant: Yes 制造商:NXP Semiconductors 功能描述:Dual monostable multivibrator, 74HC221D 制造商:NXP Semiconductors 功能描述:Monostable Multivibrator Dual 16-Pin SO
74HC221D,652 功能描述:單穩(wěn)態(tài)多諧振蕩器 DUAL MONO NONRETRIG RoHS:否 制造商:Texas Instruments 每芯片元件:1 邏輯系列:LVC 邏輯類型:Monostable Multivibrator 封裝 / 箱體:SSOP-8 傳播延遲時間:18.6 ns 高電平輸出電流:- 32 mA 低電平輸出電流:32 mA 電源電壓-最大:5.5 V 電源電壓-最小:1.65 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
74HC221D,653 功能描述:單穩(wěn)態(tài)多諧振蕩器 DUAL MONOSTABLE MULTIVIBRATOR RoHS:否 制造商:Texas Instruments 每芯片元件:1 邏輯系列:LVC 邏輯類型:Monostable Multivibrator 封裝 / 箱體:SSOP-8 傳播延遲時間:18.6 ns 高電平輸出電流:- 32 mA 低電平輸出電流:32 mA 電源電壓-最大:5.5 V 電源電壓-最小:1.65 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