TC74VHC123,221AF/AFT/AFK
2014-03-01
1
TOSHIBA CMOS Digital Integrated Circuit Silicon Monolithic
TC74VHC123AF, TC74VHC123AFT, TC74VHC123AFK
TC74VHC221AF, TC74VHC221AFT, TC74VHC221AFK
Dual Monostable Multivibrator
TC74VHC123AF/AFT/AFK Retriggerable
TC74VHC221AF/AFT/AFK Non-Retriggerable
The TC74VHC123A/221A are high speed CMOS
MONOSTABLE MULTIVIBRATOR fabricated with silicon gate
C2MOS technology.
There are two trigger inputs, A input (negative edge), and B
input (positive edge). These inputs are valid for a slow rise/fall
time signal (tr = tf = 1 s) as they are schmitt trigger inputs. This
device may also be triggered by using CLR input (positive
edge).
After triggering, the output stays in a MONOSTABLE state for
a time period determined by the external resistor and capacitor
(RX, CX). A low level at the CLR input breaks this state.
Limits for CX and RX are:
External capacitor, CX: No limit
External resistor, RX: VCC = 2.0 V more than 5 kΩ
V
CC ≥ 3.0 V more than 1 kΩ
An input protection circuit ensures that 0 to 5.5 V can be
applied to the input pins without regard to the supply voltage.
This device can be used to interface 5 V to 3 V systems and two
supply systems such as battery back up. This circuit prevents
device destruction due to mismatched supply and input voltages.
Features
• High speed: tpd = 8.1 ns (typ.) at VCC = 5 V
• Low power dissipation
Standby state: 4 μA (max) at Ta = 25°C
Active state: 600 μA (max) at Ta = 25°C
• High noise immunity: VNIH = VNIL = 28% VCC (min)
• Power down protection is equipped with all inputs.
• Balanced propagation delays: tpLH ∼
−
tpHL
• Wide operating voltage range: VCC (opr) = 2 to 5.5 V
• Pin and function compatible with 74HC123A/221A
TC74VHC123AF, TC74VHC221AF
TC74VHC123AFT, TC74VHC221AFT
TC74VHC123AFK, TC74VHC221AFK
Weight
SOP16-P-300-1.27A : 0.18 g (typ.)
TSSOP16-P-0044-0.65A : 0.06 g (typ.)
VSSOP16-P-0030-0.50 : 0.02
g
(
t
y
p.
)
Start of commercial production
1991-11
TC74VHC123,221AF/AFT/AFK
2014-03-01
2
Pin Assignment
IEC Logic Symbol
Truth Table
Inputs Outputs
A B CLR Q Q
Function
H H Output Enable
X L H L H Inhibit
H X H L H Inhibit
L H Output Enable
L H Output Enable
X X L L H Reset
X: Don’t care
VCC 16
1RX/CX
1CX
1Q
15
14
13
12
11
10
A1 1
2
3
4
5
6
7
2Q
2CX
2RX/CX
GND 8A2
9
2B
(top view)
1B
CLR1
Q1
CLR2
Q2
(2)
(1)
(3)
(15)
(14)
1CX
1RX/CX
(13) 1Q
CLR1
A1
1B
TC74VHC123A
R (4) Q1
CX
RX/CX
&
(10)
(9)
(11)
(7)
(6)
2CX
2RX/CX
(5) 2Q
CLR2
A2
2B
(12) Q2
R
CX
RX/CX
&
(2)
(1)
(3)
(15)
(14)
1CX
1RX/CX
(13) 1Q
CLR1
A1
1B
TC74VHC221A
R (4) Q1
CX
RX/CX
(10)
(9)
(11)
(7)
(6)
2CX
2RX/CX
(5) 2Q
CLR2
A2
2B
(12) Q2
1
&
R
CX
RX/CX
1
&
TC74VHC123,221AF/AFT/AFK
2014-03-01
3
Block Diagram (Note 1) (Note 2)
Note 1: CX, RX, DX are external capacitor, resistor, and diode, respectively.
Note 2: External clamping diode, DX;
The external capacitor is charged to VCC level in the wait state, i.e. when no trigger is applied.
If the supply voltage is turned off, CX is discharges mainly through the internal (parasitic) diode. If CX is
sufficiently large and VCC drops rapidly, there will be some possibility of damaging the IC through in rush
current or latch-up. If the capacitance of the supply voltage filter is large enough and VCC drops slowly, the
in rush current is automatically limited and damage to the IC is avoided.
The maximum value of forward current through the parasitic diode is ±20 mA.
In the case of a large CX, the limit of fall time of the supply voltage is determined as follows:
tf ≥ (VCC − 0.7) CX/20 mA
(tf is the time between the supply voltage turn off and the supply voltage reaching 0.4 VCC.)
In the even a system does not satisfy the above condition, an external clamping diode (DX) is needed to
protect the IC from rush current.
CX
1
2
13
4
14 15
DX
VCC
RX
CXRX/CX
3
CLR
A
B
Q
Q
CX
9
10
5
12
67
DX
VCC
RX
CXRX/CX
11
CLR
A
B
Q
Q
TC74VHC123,221AF/AFT/AFK
2014-03-01
4
System Diagram
TC74VHC123A
Timing Chart
TC74VHC123A
L H
RQD
Q
CK
RX/CX
CX
A
B
CLR
Q
Q
VCC
VCC
F/F
QP
QN
Vref
C1
Vref
C2
twOUT twOUT + trr
twOUT
trr
VIH
VIL
VCC
VOH
VOL
A
B
CLR
RX/CX
Q
VIL
VIH
VIL
VrefH
VrefL
GND
VOH
VOL
Q
VIH
TC74VHC123,221AF/AFT/AFK
2014-03-01
5
System Diagram
TC74VHC221A
Timing Chart
TC74VHC221A
L H
RQD
Q
CK
RX/CX
CX
A
B
CLR
Q
Q
VCC
F/F
QP
QN
Vref
C1
Vref
C2
twOUT twOUT
twOUT
VIH
VIL
VCC
VOH
VOL
A
B
CLR
RX/CX
Q
VIH
VIL
VIH
VIL
VrefH
VrefL
GND
VOH
Q
VOL
TC74VHC123,221AF/AFT/AFK
2014-03-01
6
Functional Description
(1) Standby state
The external capacitor (CX) is fully charged to VCC in the stand-by state. That means, before
triggering, the QP and QN transistors which are connected to the RX/CX node are in the off state. Two
comparators that relate to the timing of the output pulse, and two reference voltage supplies turn off.
The total supply current is only leakage current.
(2) Trigger operation
Trigger operation is effective in any of the following three cases. First, the condition where the A
input is low, and the B input has a rising signal; second, where the B input is high, and the A input
has a falling signal; and third, where the A input is low and the B input is high, and the CLR
input has a rising signal.
After a trigger becomes effective, comparators C1 and C2 start operating, and QN is turned on. The
external capacitor discharges through QN. The voltage level at the RX/CX node drops. If the RX/CX
voltage level falls to the internal reference voltage VrefL, the output of C1 becomes low. The flip-flop is
then reset and QN turns off. At that moment C1 stops but C2 continues operating.
After QN turns off, the voltage at the RX/CX node starts rising at a rate determined by the time
constant of external capacitor CX and resistor RX.
Upon triggering, output Q becomes high, following some delay time of the internal F/F and gates. It
stays high even if the voltage of RX/CX changes from falling to rising. When RX/CX reaches the
internal reference voltage VrefH, the output of C2 becomes low, the output Q goes low and C2 stops its
operation. That means, after triggering, when the voltage level of the RX/CX node reaches VrefH, the
IC returns to its MONOSTABLE state.
With large values of CX and RX, and ignoring the discharge time of the capacitor and internal
delays of the IC, the width of the output pulse, tw (OUT), is as follows:
tw (OUT) = 1.0 · CX · RX
(3) Retrigger operation (TC74VHC123A)
When a new trigger is applied to either input A or B while in the MONOSTABLE state, it is
effective only if the IC is charging CX. The voltage level of the RX/CX node then falls to VrefL level
again. Therefore the Q output stays high if the next trigger comes in before the time period set by CX
and RX.
If the new trigger is very close to previous trigger, such as an occurrence during the discharge cycle,
it will have no effect.
The minimum time for a trigger to be effective 2nd trigger, trr (min.), depends on VCC and CX.
(4) Reset operation
In normal operation, the CLR input is held high. If CLR is low, a trigger has no effect because
the Q output is held low and the trigger control F/F is reset. Also, QP turns on and CX is charged
rapidly to VCC.
This means if CLR is set low, the IC goes into a wait state.
TC74VHC123,221AF/AFT/AFK
2014-03-01
7
Absolute Maximum Ratings (Note)
Characteristics Symbol Rating Unit
Supply voltage range VCC −0.5 to 7.0 V
DC input voltage VIN −0.5 to 7.0 V
DC output voltage VOUT −0.5 to VCC + 0.5 V
Input diode current IIK −20 mA
Output diode current IOK ±20 mA
DC output current IOUT ±25 mA
DC VCC/ground current ICC ±50 mA
Power dissipation PD 180 mW
Storage temperature Tstg −65 to 150 °C
Note: Exceeding any of the absolute maximum ratings, even briefly, lead to deterioration in IC performance or
even destruction.
Using continuously under heavy loads (e.g. the application of high temperature/current/voltage and the
significant change in temperature, etc.) may cause this product to decrease in the reliability significantly
even if the operating conditions (i.e. operating temperature/current/voltage, etc.) are within the absolute
maximum ratings and the operating ranges.
Please design the appropriate reliability upon reviewing the Toshiba Semiconductor Reliability Handbook
(“Handling Precautions”/“Derating Concept and Methods”) and individual reliability data (i.e. reliability test
report and estimated failure rate, etc).
Operating Ranges (Note 1)
Characteristics Symbol Rating Unit
Supply voltage VCC 2.0 to 5.5 V
Input voltage VIN 0 to 5.5 V
Output voltage VOUT 0 to VCC V
Operating temperature Topr −40 to 85 °C
Input rise and fall time dt/dv 0 to 100 (VCC = 3.3 ± 0.3 V)
0 to 20 (VCC = 5 ± 0.5 V) ns/V
External capacitor CX No limitation (Note 2) F
External resistor RX ≥ 5 k (VCC = 2.0 V) (Note 2)
≥ 1 k (VCC ≥ 3.0 V) (Note 2) Ω
Note 1: The operating ranges must be maintained to ensure the normal operation of the device.
Unused inputs must be tied to either VCC or GND.
Note 2: The maximum allowable values of CX and RX are a function of leakage of capacitor CX, the leakage of
TC74VHC123A/221A, and leakage due to board layout and surface resistance.
Susceptibility to externally induced noise signals may occur for RX > 1 MΩ.
TC74VHC123,221AF/AFT/AFK
2014-03-01
8
Electrical Characteristics
DC Characteristics
Test Condition Ta = 25°C Ta =
−40 to 85°C
Characteristics Symbol
VCC (V) Min Typ. Max Min Max
Unit
High-level input
voltage VIH ―
2.0
3.0 to 5.5
1.50
VCC ×
0.7
―
―
―
―
1.50
VCC ×
0.7
―
― V
Low-level input
voltage VIL ―
2.0
3.0 to 5.5
―
―
―
―
0.50
VCC ×
0.3
―
―
0.50
VCC ×
0.3
V
IOH = −50 μA
2.0
3.0
4.5
1.9
2.9
4.4
2.0
3.0
4.5
―
―
―
1.9
2.9
4.4
―
―
―
High-level output
voltage VOH V
IN = VIH or VIL
IOH = −4 mA
IOH = −8 mA
3.0
4.5
2.58
3.94
―
―
―
―
2.48
3.80
―
―
V
IOL = 50 μA
2.0
3.0
4.5
―
―
―
0.0
0.0
0.0
0.1
0.1
0.1
―
―
―
0.1
0.1
0.1
Low-level output
voltage VOL V
IN = VIH or VIL
IOL = 4 mA
IOL = 8 mA
3.0
4.5
―
―
―
―
0.36
0.36
―
―
0.44
0.44
V
Input leakage
current IIN VIN = 5.5 V or GND 0 to 5.5 ― ― ±0.1 ― ±1.0 μA
RX/CX terminal
off-state current IIN V
IN = VCC or GND 5.5 ― ― ±0.25 ― ±2.5 μA
Quiescent supply
current ICC V
IN = VCC or GND 5.5 ― ― 4.0 ― 40.0 μA
Active-state supply
current
(Note)
ICC
VIN = VCC or GND
RX/CX = 0.5 VCC
3.0
4.5
5.5
―
―
―
160
380
560
250
500
750
―
―
―
280
650
975
μA
Note: Per circuit
TC74VHC123,221AF/AFT/AFK
2014-03-01
9
Timing Requirements (input: tr = tf = 3 ns)
Test Condition Ta = 25°C
Ta =
−40 to
85°C
Characteristics Symbol
VCC (V) Typ. Limit Limit
Unit
Minimum pulse width tw (L)
tw (H)
― 3.3 ± 0.3
5.0 ± 0.5
―
―
5.0
5.0
5.0
5.0 ns
Minimum clear width
(CLR ) tw (L) ― 3.3 ± 0.3
5.0 ± 0.5
―
―
5.0
5.0
5.0
5.0 ns
RX = 1 kΩ
CX = 100 pF
3.3 ± 0.3
5.0 ± 0.5
60
39
―
―
―
― ns
Minimum retrigger time
(Note) trr
RX = 1 kΩ
CX = 0.01 μF
3.3 ± 0.3
5.0 ± 0.5
1.5
1.2
―
―
―
― μs
Note: For TC74VHC123A only
AC Characteristics (input: tr = tf = 3 ns)
Test Condition Ta = 25°C Ta =
−40 to 85°C
Characteristics Symbol
VCC (V) CL (pF) Min Typ. Max Min Max
Unit
15 ― 13.4 20.6 1.0 24.0
3.3 ± 0.3
50 ― 15.9 24.1 1.0 27.5
15 ― 8.1 12.0 1.0 14.0
Propagation delay
time
(A, B-Q, Q)
tpLH
tpHL
―
5.0 ± 0.5
50 ― 9.6 14.0 1.0 16.0
ns
15 ― 14.5 22.4 1.0 26.0
3.3 ± 0.3
50 ― 17.0 25.9 1.0 29.5
15 ― 8.7 12.9 1.0 15.0
Propagation delay
time
(CLR trigger-Q, Q)
tpLH
tpHL
―
5.0 ± 0.5
50 ― 10.2 14.9 1.0 17.0
ns
15 ― 10.3 15.8 1.0 18.5
3.3 ± 0.3
50 ― 12.8 19.3 1.0 22.0
15 ― 6.3 9.4 1.0 11.0
Propagation delay
time
(CLR -Q, Q)
tpLH
tpHL
―
5.0 ± 0.5
50 ― 7.8 11.4 1.0 13.0
ns
3.3 ± 0.3 ― 160 240 ― 300CX = 28 pF
RX = 2 kΩ 5.0 ± 0.5
50
― 133 200 ― 240
ns
3.3 ± 0.3 90 100 110 90 110CX = 0.01 μF
RX = 10 kΩ 5.0 ± 0.5
50
90 100 110 90 110
μs
3.3 ± 0.3 0.9 1.0 1.1 0.9 1.1
Output pulse width twOUT
CX = 0.1 μF
RX = 10 kΩ 5.0 ± 0.5
50
0.9 1.0 1.1 0.9 1.1
ms
Output pulse width
error between circuits
(in same package)
ΔtwOUT ― ― ±1 ― ― ― %
Input capacitance CIN ― ― 4 10 ― 10 pF
Power dissipation
capacitance CPD (Note) ― 73 ― ― ― pF
Note: CPD is defined as the value of the internal equivalent capacitance which is calculated from the operating
current consumption without load.
Average operating current can be obtained by the equation:
ICC (opr) = CPD·VCC·fIN + ICC’·Duty/100 + ICC/2 (per circuit)
(ICC’: active supply current)
(Duty: %)
TC74VHC123,221AF/AFT/AFK
2014-03-01
10
Input Equivalent Circuit
External capacitor CX (pF)
twOUT – CX Characteristics (typ.)
Output pulse width twOUT (μs)
Supply voltage VCC (V)
trr – VCC Characteristics (typ.)
(TC74VHC123A)
Minimum retrigger time trr (μs)
Supply voltage VCC (V)
Output Pulse Width Constant K − Supply Voltage (typ.)
(external resistor (RX) = 10 kΩ: twOUT = K·CX·RX)
Output pulse width constant K
0.01
0
0.1
1
10
1 2 3 4 5 6
CX = 0.01 μF
CX = 1000 pF
CX = 100 pF
Ta = 25 ° C
103
10−1
102
102
10
1
103 104
VCC = 4.5 V
CL = 50 pF
RX = 1 MΩ
RX = 100 kΩ
RX = 10 kΩ
RX = 1 kΩ
1.2
2 3 4 5 6
1.1
1.0
CX = 0.01 μF
CX = 1000 pF
CX = 1 μF, CX = 0.1 μF
INPUT
TC74VHC123,221AF/AFT/AFK
2014-03-01
11
Package Dimensions
Weight: 0.18 g (typ.)
TC74VHC123,221AF/AFT/AFK
2014-03-01
12
Package Dimensions
Weight: 0.06 g (typ.)
TC74VHC123,221AF/AFT/AFK
2014-03-01
13
Package Dimensions
Weight: 0.02 g (typ.)
TC74VHC123,221AF/AFT/AFK
2014-03-01
14
RESTRICTIONS ON PRODUCT USE
• Toshiba Corporation, and its subsidiaries and affiliates (collectively "TOSHIBA"), reserve the right to make changes to the information
in this document, and related hardware, software and systems (collectively "Product") without notice.
• This document and any information herein may not be reproduced without prior written permission from TOSHIBA. Even with
TOSHIBA's written permission, reproduction is permissible only if reproduction is without alteration/omission.
• Though TOSHIBA works continually to improve Product's quality and reliability, Product can malfunction or fail. Customers are
responsible for complying with safety standards and for providing adequate designs and safeguards for their hardware, software and
systems which minimize risk and avoid situations in which a malfunction or failure of Product could cause loss of human life, bodily
injury or damage to property, including data loss or corruption. Before customers use the Product, create designs including the
Product, or incorporate the Product into their own applications, customers must also refer to and comply with (a) the latest versions of
all relevant TOSHIBA information, including without limitation, this document, the specifications, the data sheets and application notes
for Product and the precautions and conditions set forth in the "TOSHIBA Semiconductor Reliability Handbook" and (b) the
instructions for the application with which the Product will be used with or for. Customers are solely responsible for all aspects of their
own product design or applications, including but not limited to (a) determining the appropriateness of the use of this Product in such
design or applications; (b) evaluating and determining the applicability of any information contained in this document, or in charts,
diagrams, programs, algorithms, sample application circuits, or any other referenced documents; and (c) validating all operating
parameters for such designs and applications. TOSHIBA ASSUMES NO LIABILITY FOR CUSTOMERS' PRODUCT DESIGN OR
APPLICATIONS.
• PRODUCT IS NEITHER INTENDED NOR WARRANTED FOR USE IN EQUIPMENTS OR SYSTEMS THAT REQUIRE
EXTRAORDINARILY HIGH LEVELS OF QUALITY AND/OR RELIABILITY, AND/OR A MALFUNCTION OR FAILURE OF WHICH
MAY CAUSE LOSS OF HUMAN LIFE, BODILY INJURY, SERIOUS PROPERTY DAMAGE AND/OR SERIOUS PUBLIC IMPACT
("UNINTENDED USE"). Except for specific applications as expressly stated in this document, Unintended Use includes, without
limitation, equipment used in nuclear facilities, equipment used in the aerospace industry, medical equipment, equipment used for
automobiles, trains, ships and other transportation, traffic signaling equipment, equipment used to control combustions or explosions,
safety devices, elevators and escalators, devices related to electric power, and equipment used in finance-related fields. IF YOU USE
PRODUCT FOR UNINTENDED USE, TOSHIBA ASSUMES NO LIABILITY FOR PRODUCT. For details, please contact your
TOSHIBA sales representative.
• Do not disassemble, analyze, reverse-engineer, alter, modify, translate or copy Product, whether in whole or in part.
• Product shall not be used for or incorporated into any products or systems whose manufacture, use, or sale is prohibited under any
applicable laws or regulations.
• The information contained herein is presented only as guidance for Product use. No responsibility is assumed by TOSHIBA for any
infringement of patents or any other intellectual property rights of third parties that may result from the use of Product. No license to
any intellectual property right is granted by this document, whether express or implied, by estoppel or otherwise.
• ABSENT A WRITTEN SIGNED AGREEMENT, EXCEPT AS PROVIDED IN THE RELEVANT TERMS AND CONDITIONS OF SALE
FOR PRODUCT, AND TO THE MAXIMUM EXTENT ALLOWABLE BY LAW, TOSHIBA (1) ASSUMES NO LIABILITY
WHATSOEVER, INCLUDING WITHOUT LIMITATION, INDIRECT, CONSEQUENTIAL, SPECIAL, OR INCIDENTAL DAMAGES OR
LOSS, INCLUDING WITHOUT LIMITATION, LOSS OF PROFITS, LOSS OF OPPORTUNITIES, BUSINESS INTERRUPTION AND
LOSS OF DATA, AND (2) DISCLAIMS ANY AND ALL EXPRESS OR IMPLIED WARRANTIES AND CONDITIONS RELATED TO
SALE, USE OF PRODUCT, OR INFORMATION, INCLUDING WARRANTIES OR CONDITIONS OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE, ACCURACY OF INFORMATION, OR NONINFRINGEMENT.
• Do not use or otherwise make available Product or related software or technology for any military purposes, including without
limitation, for the design, development, use, stockpiling or manufacturing of nuclear, chemical, or biological weapons or missile
technology products (mass destruction weapons). Product and related software and technology may be controlled under the
applicable export laws and regulations including, without limitation, the Japanese Foreign Exchange and Foreign Trade Law and the
U.S. Export Administration Regulations. Export and re-export of Product or related software or technology are strictly prohibited
except in compliance with all applicable export laws and regulations.
• Please contact your TOSHIBA sales representative for details as to environmental matters such as the RoHS compatibility of Product.
Please use Product in compliance with all applicable laws and regulations that regulate the inclusion or use of controlled substances,
including without limitation, the EU RoHS Directive. TOSHIBA ASSUMES NO LIABILITY FOR DAMAGES OR LOSSES
OCCURRING AS A RESULT OF NONCOMPLIANCE WITH APPLICABLE LAWS AND REGULATIONS.
