Philips 74HC123, 74HCT123 DATA SHEET

74HC123; 74HCT123

Dual retriggerable monostable multivibrator with reset

Rev. 03 — 11 May 2004	Product data sheet

1. General description

The 74HC123; 74HCT123 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 74HC123; 74HCT123 are dual retriggerable monostable multivibrators with output pulse width control by three methods:

1.The basic pulse time is programmed by selection of an external resistor (REXT) and capacitor (CEXT).

2.Once triggered, the basic output pulse width may be extended by retriggering the gated active LOW-going edge input (nA) or the active HIGH-going edge input (nB). By repeating this process, the output pulse period (nQ = HIGH, nQ = LOW) can be made as long as desired. Alternatively an output delay can be terminated at any time by a LOW-going edge on input nRD, which also inhibits the triggering.

3.An internal connection from nRD to the input gates makes it possible to trigger the circuit by a HIGH-going signal at input nRD as shown in the function table.

Schmitt-trigger action in the nA and nB inputs, makes the circuit highly tolerant to slower input rise and fall times.

The 74HC123; 74HCT123 is identical to the 74HC423; 74HCT423 but can be triggered via the reset input.

2. Features

■DC triggered from active HIGH or active LOW inputs

■Retriggerable for very long pulses up to 100 % duty factor

■Direct reset terminates output pulse

■Schmitt-trigger action on all inputs except for the reset input

■ESD protection:

HBM EIA/JESD22-A114-B exceeds 2000 V

MM EIA/JESD22-A115-A exceeds 200 V.

■Specified from −40 °C to +80 °C and from −40 °C to +125 °C.

Philips Semiconductors			74HC123; 74HCT123
			Dual retriggerable monostable multivibrator with reset

3. Quick reference data

Table 1: Quick reference data

GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns

Symbol

Parameter

Conditions

Min

Typ

Max

Unit

Type 74HC123

tPHL, tPLH

propagation delay

CEXT = 0 pF; REXT = 5 kΩ;

-

26

-

ns

CL = 15 pF; VCC = 5 V

nA,

nB to nQ, nQ

propagation delay

CEXT = 0 pF; REXT = 5 kΩ;

-

20

-

ns

CL = 15 pF; VCC = 5 V

nRD to nQ, nQ

CI

input capacitance

-

3.5

-

pF

CPD

power dissipation

[1] [2]

-

54

-

pF

capacitance per

monostable

Type 74HCT123

tPHL, tPLH

propagation delay

CEXT = 0 pF; REXT = 5 kΩ;

-

26

-

ns

CL = 15 pF; VCC = 5 V

nA,

nB to nQ, nQ

propagation delay

CEXT = 0 pF; REXT = 5 kΩ;

-

23

-

ns

CL = 15 pF; VCC = 5 V

nRD to nQ, nQ

CI

input capacitance

-

3.5

-

pF

CPD

power dissipation

[1] [3]

-

56

-

pF

capacitance per

monostable

[1]CPD is used to determine the dynamic power dissipation (PD in mW):

PD = CPD ´ VCC2 ´ fi + å(CL ´ VCC2 ´ fo) + 0.75 ´ CEXT ´ VCC2 ´ fo + D ´ 16 ´ VCC where: fi = input frequency in MHz;

fo = output frequency in MHz; D = duty factor in %;

CL = output load capacitance in pF; VCC = supply voltage in V;

CEXT = timing capacitance in pF; å (CL ´ VCC2 ´ fo) sum of outputs.

[2]For 74HC123 the condition is VI = GND to VCC.

[3]For 74HCT123 the condition is VI = GND to VCC - 1.5 V.

4.Ordering information

Table 2: Ordering information

Type number	Package
	Temperature range	Name	Description	Version
74HC123N	−40 °C to +125 °C	DIP16	plastic dual in-line package; 16 leads (300 mil);	SOT38-1
			long body
74HCT123N	−40 °C to +125 °C
74HC123D	−40 °C to +125 °C	SO16	plastic small outline package; 16 leads; body width	SOT109-1
			3.9 mm
74HCT123D	−40 °C to +125 °C

9397 750 13024

© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

Product data sheet

Rev. 03 — 11 May 2004

2 of 26

Philips Semiconductors					74HC123; 74HCT123
					Dual retriggerable monostable multivibrator with reset
Table 2: Ordering information …continued
Type number			Package
			Temperature range	Name	Description	Version
74HC123DB			−40 °C to +125 °C	SSOP16	plastic shrink small outline package; 16 leads;	SOT338-1
					body width 5.3 mm
74HCT123DB			−40 °C to +125 °C
74HC123PW			−40 °C to +125 °C	TSSOP16	plastic thin shrink small outline package; 16 leads;	SOT403-1
					body width 4.4 mm
74HCT123PW			−40 °C to +125 °C

5. Functional diagram

		1CEXT	14
		1REXT/CEXT	15
		S	13
		1Q
1	1A	Q
		T
		1Q	4
2	1B	Q
		RD
3	1RD	2CEXT	6
		2REXT/CEXT	7
		S	5
		2Q
9	2A	Q
		T
		2Q	12
10	2B	Q
		RD
11	2RD
		001aaa610

Fig 1. Functional diagram.

9397 750 13024

© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

Product data sheet

Rev. 03 — 11 May 2004

3 of 26

Philips Semiconductors			74HC123; 74HCT123
			Dual retriggerable monostable multivibrator with reset

																					1CEXT			14
																					2CEXT			6
														1REXT/CEXT										15
														2REXT/CEXT										7
												S									1Q			13
																	Q
																					2Q			5
1	1A
9										T
	2A
																					1Q			4
2	1B																Q
											RD										2Q			12
10	2B
3
	1RD																				mna515
11
	2RD

14

CX

15 RCX 13

1

&

2

		4
3	R
6	CX
7	RCX	5
9	&
10
		12
11	R
		mna516

Fig 2. Logic symbol.

Fig 3. IEC logic symbol.

			REXT/CEXT
			VCC
RD			Q
	R	R	Q
	CL	CL
	VCC	VCC
			R
		CL
			mna518
A		CL	CL
B		R
Fig 4.	Logic diagram.

9397 750 13024

© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

Product data sheet

Rev. 03 — 11 May 2004

4 of 26

Philips Semiconductors							74HC123; 74HCT123
			Dual retriggerable monostable multivibrator with reset
6. Pinning information
		6.1 Pinning
								VCC
				1A		1	16
				1B		2	15	1REXT/CEXT
						3	14	1CEXT
			1RD
						4	13	1Q
				1Q
				2Q		5	123
							12	2Q
			2CEXT			6	11
								2RD
			2REXT/CEXT			7	10	2B
			GND			8	9
								2A
							001aaa698
			Fig 5. Pin configuration.

6.2 Pin description

Table 3:	Pin description
Pin	Symbol					Description
1						trigger inputs (negative-edge triggered)
	1A
2	1B					trigger inputs (positive-edge triggered)
3						direct reset LOW and trigger action at positive edge
	1RD
4						outputs (active LOW)
	1Q
5	2Q					outputs (active HIGH)
6	2CEXT					external capacitor connection
7	2REXT/CEXT					external resistor and capacitor connection
8	GND					ground (0 V)
9						trigger inputs (negative-edge triggered)
	2A
10	2B					trigger inputs (positive-edge triggered)
11						direct reset LOW and trigger action at positive edge
	2RD
12						outputs (active LOW)
	2Q
13	1Q					outputs (active HIGH)
14	1CEXT					external capacitor connection
15	1REXT/CEXT					external resistor and capacitor connection
16	VCC					supply voltage

9397 750 13024

© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

Product data sheet

Rev. 03 — 11 May 2004

5 of 26

Philips Semiconductors

74HC123; 74HCT123

Dual retriggerable monostable multivibrator with reset

7. Functional description

7.1 Function table

Table 4: Function table

[1]

Input

Output

nB

nQ

nRD

nA

nQ

L

X

X

L

H

X

H

X

L

[2]

H

[2]

X

X

L

L

[2]

H

[2]

H

L

−

H

↓

H

−

L

H

[1]H = HIGH voltage level L = LOW voltage level

X = don’t care

− = LOW-to-HIGH transition

↓ = HIGH-to-LOW transition

= one HIGH level output pulse

=one LOW level output pulse.

[2]If the monostable was triggered before this condition was established, the pulse will continue as programmed.

8.Limiting values

Table 5: Limiting values

In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to GND (ground = 0 V).

Symbol	Parameter	Conditions	Min	Max	Unit
VCC	supply voltage		−0.5	+7	V
IIK	input diode current	VI < −0.5 V or VI > VCC + 0.5 V	-	±20	mA
IOK	output diode current	VO < −0.5 V or	-	±20	mA
		VO > VCC + 0.5 V
IO	output source or sink	VO = −0.5 V to VCC + 0.5 V	-	±25	mA
	current, except for pins
	nREXT/CEXT
ICC, IGND	VCC or GND current		-	±50	mA
Tstg	storage temperature		−65	+150	°C
Ptot	power dissipation

	DIP16 package	[1]	-	750	mW
	SO16, SSOP16 and	[2]	-	500	mW
	TSSOP16 packages

[1]Above 70 °C: Ptot derates linearly with 12 mW/K.

[2]Above 70 °C: Ptot derates linearly with 8 mW/K.

9397 750 13024

© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

Product data sheet

Rev. 03 — 11 May 2004

6 of 26

Philips Semiconductors							74HC123; 74HCT123
							Dual retriggerable monostable multivibrator with reset
9. Recommended operating conditions
			Table 6:	Recommended operating conditions
			Symbol	Parameter			Conditions	Min	Typ	Max	Unit
			Type 74HC123
			VCC	supply voltage				2.0	5.0	6.0	V
			VI	input voltage				0	-	VCC	V
			VO	output voltage				0	-	VCC	V
			tr, tf	input rise and fall			VCC = 2.0 V	-	-	1000	ns
				times for nRD input
							VCC = 4.5 V	-	6.0	500	ns
							VCC = 6.0 V	-	-	400	ns
			Tamb	operating ambient			see Section 10 and 11	−40	-	+125	°C
				temperature
			Type 74HCT123
			VCC	supply voltage				4.5	5.0	5.5	V
			VI	input voltage				0	-	VCC	V
			VO	output voltage				0	-	VCC	V
			tr, tf	input rise and fall			VCC = 4.5 V	-	6.0	500	ns
				times for nRD input
			Tamb	operating ambient			see Section 10 and 11	−40	-	+125	°C
				temperature

10. Static characteristics

Table 7: Static characteristics type 74HC123

At recommended operating conditions; voltages are referenced to GND (ground = 0 V).

Symbol	Parameter	Conditions	Min	Typ	Max	Unit
Tamb = 25 °C
VIH	HIGH-level input voltage	VCC = 2.0 V	1.5	1.2	-	V
		VCC = 4.5 V	3.15	2.4	-	V
		VCC = 6.0 V	4.2	3.2	-	V
VIL	LOW-level input voltage	VCC = 2.0 V	-	0.8	0.5	V
		VCC = 4.5 V	-	2.1	1.35	V
		VCC = 6.0 V	-	2.8	1.8	V
VOH	HIGH-level output voltage	VI = VIH or VIL

IO = −20 μA; VCC = 2.0 V	1.9	2.0	-	V
IO = −20 μA; VCC = 4.5 V	4.4	4.5	-	V
IO = −20 μA; VCC = 6.0 V	5.9	6.0	-	V
IO = −4 mA; VCC = 4.5 V	3.98	4.32	-	V
IO = −5.2 mA; VCC = 6.0 V	5.48	5.81	-	V

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© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

Product data sheet

Rev. 03 — 11 May 2004

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Philips Semiconductors				74HC123; 74HCT123
				Dual retriggerable monostable multivibrator with reset
Table 7:			Static characteristics type 74HC123 …continued
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol			Parameter	Conditions	Min	Typ	Max	Unit
VOL			LOW-level output voltage	VI = VIH or VIL
				IO = 20 μA; VCC = 2.0 V	-	0	0.1	V
				IO = 20 μA; VCC = 4.5 V	-	0	0.1	V
				IO = 20 μA; VCC = 6.0 V	-	0	0.1	V
				IO = 4 mA; VCC = 4.5 V	-	0.15	0.26	V
				IO = 5.2 mA; VCC = 6.0 V	-	0.16	0.26	V
ILI			input leakage current	VI = VCC or GND; VCC = 6.0 V	-	-	±0.1	μA
ICC			quiescent supply current	VI = VCC or GND; IO = 0 A;	-	-	8.0	μA
				VCC = 6.0 V
CI			input capacitance		-	3.5	-	pF
Tamb = −40 °C to +85 °C
VIH			HIGH-level input voltage	VCC = 2.0 V	1.5	-	-	V
				VCC = 4.5 V	3.15	-	-	V
				VCC = 6.0 V	4.2	-	-	V
VIL			LOW-level input voltage	VCC = 2.0 V	-	-	0.5	V
				VCC = 4.5 V	-	-	1.35	V
				VCC = 6.0 V	-	-	1.8	V
VOH			HIGH-level output voltage	VI = VIH or VIL
				IO = −20 μA; VCC = 2.0 V	1.9	-	-	V
				IO = −20 μA; VCC = 4.5 V	4.4	-	-	V
				IO = −20 μA; VCC = 6.0 V	5.9	-	-	V
				IO = −4 mA; VCC = 4.5 V	3.84	-	-	V
				IO = −5.2 mA; VCC = 6.0 V	5.34	-	-	V
VOL			LOW-level output voltage	VI = VIH or VIL
				IO = 20 μA; VCC = 2.0 V	-	-	0.1	V
				IO = 20 μA; VCC = 4.5 V	-	-	0.1	V
				IO = 20 μA; VCC = 6.0 V	-	-	0.1	V
				IO = 4 mA; VCC = 4.5 V	-	-	0.33	V
				IO = 5.2 mA; VCC = 6.0 V	-	-	0.33	V
ILI			input leakage current	VI = VCC or GND; VCC = 6.0 V	-	-	±1.0	μA
ICC			quiescent supply current	VI = VCC or GND; IO = 0 A;	-	-	80	μA
				VCC = 6.0 V
Tamb = −40 °C to +125 °C
VIH			HIGH-level input voltage	VCC = 2.0 V	1.5	-	-	V
				VCC = 4.5 V	3.15	-	-	V
				VCC = 6.0 V	4.2	-	-	V
VIL			LOW-level input voltage	VCC = 2.0 V	-	-	0.5	V
				VCC = 4.5 V	-	-	1.35	V
				VCC = 6.0 V	-	-	1.8	V

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Product data sheet

Rev. 03 — 11 May 2004

8 of 26