SA555

Part: NE555 / SA555 / NA555 / SE555 precision timers — Texas Instruments (the filename says SN74AHC1G14DBVR, but the datasheet content is for the 555 timer family)

Type: Precision Timer (555)

Description: Precision timing circuits for monostable and astable operation, with 4.5–16 V supply (18 V for SE555), ±200 mA TTL-compatible output drive and timing from microseconds to hours.

Operating Conditions:

• Supply voltage: 4.5–16 V (NA555, NE555, SA555); 4.5–18 V (SE555)
• Operating temperature: grade-dependent: NE555 0 to 70 °C, SA555 -40 to 85 °C, NA555 -40 to 105 °C, SE555 -55 to 125 °C
• Output current: ±200 mA (recommended maximum)

Absolute Maximum Ratings:

• Max supply voltage: 18 V
• Max output current: ±225 mA
• Max operating virtual junction temperature: 150 °C
• Storage temperature: -65 to 150 °C

Key Specs:

• THRES voltage level (VCC = 15 V, TA = 25 °C): 10 V typ (NE/SA/NA555: 8.8–11.2 V; SE555: 9.4–10.6 V)
• TRIG voltage level (VCC = 15 V): 5 V typ; (VCC = 5 V): 1.67 V typ
• Supply current, output low, no load: 10 mA typ at 15 V (15 mA max NE/SA/NA555); 3 mA typ at 5 V (6 mA max)
• Supply current, output high, no load: 9 mA typ at 15 V; 2 mA typ at 5 V
• Low-level output voltage (VCC = 15 V, IOL = 10 mA): 0.1 V typ; at IOL = 100 mA: 2 V typ
• High-level output voltage (VCC = 15 V, IOH = -100 mA): 13.3 V typ
• Initial timing error, monostable (TA = 25 °C): 1% typ (NE/SA/NA555); 0.5% typ (SE555)
• Temperature coefficient of timing, monostable: 50 ppm/°C typ (NE/SA/NA555); 30 ppm/°C typ (SE555)
• Output rise/fall time (CL = 15 pF): 100 ns typ

Features:

• Timing from microseconds to hours
• Adjustable duty cycle
• Astable or monostable operation
• TTL-compatible output can sink or source up to 200 mA
• Timing interval independent of supply voltage when the supply is constant
• RESET input overrides all other inputs

Applications:

• Monostable time delays
• Astable oscillators and multivibrators
• Missing-pulse detector
• Frequency divider
• Pulse-width modulation

Package:

• PDIP (P)
• SOIC (D)
• SOP (PS)
• TSSOP (PW)
• CDIP (JG)
• LCCC (FK)

• Timing From Microseconds to Hours

SLFS022G-SEPTEMBER 1973-REVISED MARCH 2008

• Adjustable Duty Cycle
• Astable or Monostable Operation

VCC = 5 V to 15 V, TA = 25 ° C (unless otherwise noted)

PARAMETER	TEST CONDITIONS	TEST CONDITIONS	SE555 - MIN	SE555 - TYP	SE555 - MAX	NA555 NE555 SA555 - MIN	NA555 NE555 SA555 - TYP	NA555 NE555 SA555 - MAX	UNIT
THRES voltage level	V CC = 15 V	V CC = 15 V	9.4	10	10.6	8.8	10	11.2	V
	V CC = 5 V	V CC = 5 V	2.7	3.3	4	2.4	3.3	4.2
THRES current (1)				30	250		30	250	nA
TRIG voltage level	V CC = 15 V	T A = -55 ° C to 125 ° C	4.8	5	5.2	4.5	5	5.6	V
TRIG voltage level		T A = -55 ° C to 125 ° C	3		6				V
TRIG voltage level	V CC = 5 V	T A = -55 ° C to 125 ° C	1.45	1.67	1.9	1.1	1.67	2.2
TRIG voltage level		T A = -55 ° C to 125 ° C			1.9
TRIG current	TRIG at 0 V			0.5	0.9		0.5	2	μ A
RESET voltage level			0.3	0.7	1	0.3	0.7	1	V
RESET voltage level	T A = -55 ° C to 125 ° C				1.1				V
RESET current	RESET at V CC	RESET at V CC		0.1	0.4		0.1	0.4
RESET current	RESET at 0 V	RESET at 0 V		-0.4	-1		-0.4	-1.5	mA
DISCH switch off-state current				20	100		20	100	nA
CONT voltage (open circuit)	V = 15 V		9.6	10	10.4	9	10	11
CONT voltage (open circuit)	CC	T A = -55 ° C to 125 ° C	9.6		10.4
CONT voltage (open circuit)	V CC = 5 V	T A = -55 ° C to 125 ° C	2.9	3.3	3.8	2.6	3.3	4	V
Low-level output voltage	V CC = 15 V, I OL = 10 mA		2.9		3.8			0.25
Low-level output voltage				0.1	0.15		0.1
Low-level output voltage		T A = -55 ° C to 125 ° C			0.2
Low-level output voltage	V = 15 V, I = 50 mA			0.4	0.5		0.4	0.75
Low-level output voltage	CC OL	T A = -55 ° C to 125 ° C			1
Low-level output voltage	V = 15 V, I = 100 mA			2	2.2		2	2.5
Low-level output voltage	CC OL	T A = -55 ° C to 125 ° C			2.7				V
Low-level output voltage	V CC = 15 V, I OL = 200 mA			2.5			2.5
Low-level output voltage	V CC = 5 V, I OL = 3.5 mA	T A = -55 ° C to 125 ° C			0.35		0.1
Low-level output voltage	V = 5 V, I = 5 mA			0.1	0.2			0.35
Low-level output voltage	CC OL	T = -55 ° C to 125 °			0.8 0.25
Low-level output voltage	V CC = 5 V, I OL = 8 mA	A C		0.15		12.75	0.15	0.4
High-level output voltage	V CC = 15 V, I OL = -100 mA	T A = -55 ° C to 125 ° C	13 12	13.3			13.3		V
High-level output voltage	V CC = 15 V, I OH = -200 mA			12.5			12.5		V
High-level output voltage			3	3.3		2.75	3.3		V
High-level output voltage	V CC = 15 V, I OL = -100 mA	T A = -55 ° C to 125 ° C	2						V
	Output low, No load	V CC = 15 V		10	12		10	15
		V CC = 5 V		3	5		3	6
Supply current		V CC = 15 V		9	10		9	13	mA
	Output high, No load	V CC = 5 V		2	4		2	5

SLFS022G-SEPTEMBER 1973-REVISED MARCH 2008

over operating free-air temperature range (unless otherwise noted)

			MIN	MAX	UNIT
V CC	Supply voltage (2)	Supply voltage (2)		18	V
V I	Input voltage	CONT, RESET, THRES, TRIG		V CC	V
I O	Output current	Output current		±225	mA
θ JA	Package thermal impedance (3)(4)	D package		97	° C/W
θ JA	Package thermal impedance (3)(4)	P package		85	° C/W
θ JA	Package thermal impedance (3)(4)	PS package		95	° C/W
θ JA	Package thermal impedance (3)(4)	PW package		149	° C/W
θ JC	Package thermal impedance (5)(6)	FK package		5.61	° C/W
θ JC	Package thermal impedance (5)(6)	JG package		14.5	° C/W
T J	Operating virtual junction temperature	Operating virtual junction temperature		150	° C
	Case temperature for 60 s	FK package		260	° C
	Lead temperature 1, 6 mm (1/16 in) from case for 60 s	JG package		300	° C
T stg	Storage temperature range	Storage temperature range	-65	150	° C

over operating free-air temperature range (unless otherwise noted)

			MIN	MAX	UNIT
V CC	Supply voltage	NA555, NE555, SA555	4.5	16	V
V CC		SE555	4.5	18	V
V I	Input voltage	CONT, RESET, THRES, and TRIG		V CC	V
I O	Output current			±200	mA
T A	Operating free-air temperature	NA555	-40	105	° C
T A		NE555	0	70	° C
T A		SA555	-40	85	° C
T A		SE555	-55	125	° C

SLFS022G-SEPTEMBER 1973-REVISED MARCH 2008

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Figure 10. Typical Monostable Waveforms

Figure 11. Output Pulse Duration vs Capacitance

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As shown in Figure 12, adding a second resistor, RB, to the circuit of Figure 9 and connecting the trigger input to the threshold input causes the timer to self-trigger and run as a multivibrator. The capacitor C charges through RA and RB and then discharges through RB only. Therefore, the duty cycle is controlled by the values of RA and RB.

ÏÏÏÏÏ ÏÏÏÏÏ Astable Operation

This astable connection results in capacitor C charging and discharging between the threshold-voltage level ( ≈ 0.67 × VCC) and the trigger-voltage level ( ≈ 0.33 × VCC). As in the monostable circuit, charge and discharge times (and, therefore, the frequency and duty cycle) are independent of the supply voltage.

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NOTE A: Decoupling CONT voltage to ground with a capacitor can improve operation. This should be evaluated for individual applications. Pin numbers shown are for the D, JG, P, PS, and PW packages.

Figure 12. Circuit for Astable Operation

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ÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎ Figure 13. Typical Astable Waveforms ÎÎÎ

SLFS022G-SEPTEMBER 1973-REVISED MARCH 2008

Figure 12 shows typical waveforms generated during astable operation. The output high-level duration tH and low-level duration tL can be calculated as follows:

Other useful relationships are shown below.

$$\text{Output driver duty cycle} = \frac{t_L}{t_H + t_L} = \frac{R_B}{R_A + 2R_B}$$

Output waveform duty cycle