View 74HC423U_8971387.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

d a t a sh eet product speci?cation supersedes data of december 1990 file under integrated circuits, ic06 1998 jul 08 integrated circuits 74hc/hct423 dual retriggerable monostable multivibrator with reset for a complete data sheet, please also download: the ic06 74hc/hct/hcu/hcmos logic family specifications the ic06 74hc/hct/hcu/hcmos logic package information the ic06 74hc/hct/hcu/hcmos logic package outlines
1998 jul 08 2 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 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 output capability: standard (except for nr ext /c ext ) i cc category: msi general description the 74hc/hct423 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/hct423 are dual retriggerable monostable multivibrators with output pulse width control by two methods. the basic pulse time is programmed by selection of an external resistor (r ext ) and capacitor (c ext ). the external resistor and capacitor are normally connected as shown in fig.6. once triggered, the basic output pulse width may be extended by retriggering the gated active low-going edge input (n a) or the active high-going edge input (nb). by repeating this process, the output pulse period (nq = high, n q = low) can be made as long as desired. when n r d is low, it forces the nq output low, the n q output high and also inhibits the triggering. figures 7 and 8 illustrate pulse control by reset. the basic output pulse width is essentially determined by the values of the external timing components r ext and c ext . for pulse widths, when c ext < 10 000 pf, see fig.9. when c ext > 10 000 pf, the typical output pulse width is defined as: t w = 0.45 r ext c ext (typ.), where, t w = pulse width in ns; r ext = external resistor in k w ; c ext = external capacitor in pf. schmitt-trigger action in the n a and nb inputs, makes the circuit highly tolerant to slower input rise and fall times. the 423 is identical to the 123 but cannot be triggered via the reset input. 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 m w): p d = c pd v cc 2 f i +? (c l v cc 2 f o ) + 0.75 c ext v cc 2 f o + d 16 v cc where: f i = input frequency in mhz f o = output frequency in mhz d = duty factor in % ? (c l v cc 2 f o ) = sum of outputs c l = output load capacitance in pf v cc = supply voltage in v c ext = timing capacitance in pf 2. 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 symbol parameter conditions typical unit hc hct t phl / t plh propagation delay c l = 15 pf; v cc = 5 v; r ext =5 k w ; c ext = 0 pf n a, nb to nq, n q2526ns n r d to nq, n q2022ns c i input capacitance 3.5 3.5 pf t w minimum output pulse width nq, n q notes 1 and 2 75 75 ns
1998 jul 08 3 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 ordering information pin description type number package name description version 74hc423n; 74hct423n dip16 plastic dual in-line package; 16 leads (300 mil); long body sot38-1 74hc423d; 74hct423d so16 plastic small outline package; 16 leads; body width 3.9 mm; low stand-off height sot109-1 pin no. symbol name and function 1, 9 1 a, 2 a trigger inputs (negative-edge triggered) 2, 10 1b, 2b trigger inputs (positive-edge triggered) 3, 11 1 r d ,2 r d direct reset action (active low) 4, 12 1 q, 2 q outputs (active low) 72r ext /c ext external resistor/capacitor connection 8 gnd ground (0 v) 13, 5 1q, 2q outputs (active high) 14, 6 1c ext ,2c ext external capacitor connection 15 1r ext /c ext external resistor/capacitor connection 16 v cc positive supply voltage fig.1 pin configuration. fig.2 fig.3 iec logic symbol.
1998 jul 08 4 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 function table notes 1. h = high voltage level l = low voltage level x = dont 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. inputs outputs n r d n anb nq n q lxx l h xhxl (2) h (2) xxll (2) h (2) hl - h h fig.4 functional diagram.
1998 jul 08 5 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 fig.5 logic diagram. it is recommended to ground pins 6 (2c ext ) and 14 (1c ext ) externally to pin 8 (gnd). fig.6 timing component connections.
1998 jul 08 6 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 dc characteristics for 74hc for the dc characteristics see 74hc/hct/hcu/hcmos logic family specifications . output capability: standard (except for nr ext /c ext ) i cc category: msi ac characteristics for 74hc gnd = 0 v; t r = t f = 6 ns; c l = 50 pf symbol parameter t amb ( c) unit test conditions 74hc v cc (v) waveforms/ notes + 25 - 40 to + 85 - 40 to + 125 min. typ. max min max min. max. t phl / t plh propagation delay n a, nb to n q, nq 80 255 320 385 ns 2.0 c ext = 0 pf; r ext =5 k w 29 51 64 77 4.5 23 43 54 65 6.0 t phl / t plh propagation delay n r d to nq, n q 66 215 270 325 ns 2.0 c ext = 0 pf; r ext =5 k w 24 43 54 65 4.5 19 37 46 55 6.0 t thl / t tlh output transition time 19 75 95 110 ns 2.0 7 15 19 22 4.5 6 13 16 19 6.0 t w trigger pulse width n a = low 100 11 125 150 ns 2.0 fig.7 20 4 25 30 4.5 17 3 21 26 6.0 t w trigger pulse width nb = high 100 17 125 150 ns 2.0 fig.7 20 6 25 30 4.5 17 5 21 26 6.0 t w reset pulse width n r d = low 100 14 125 150 ns 2.0 fig.8 20 5 25 30 4.5 17 4 21 26 6.0 t w output pulse width nq = high n q = low 450 -- m s 5.0 c ext = 100 nf; r ext = 10 k w ; figs 7 and 8 t w output pulse width nq = high n q = low 75 -- ns 5.0 c ext = 0 pf; r ext =5 k w ; note 1; figs 7 and 8 t rt retrigger time n a, nb 110 -- ns 5.0 c ext = 0 pf; r ext =5 k w ; note 2; fig. 7 r ext external timing resistor 10 2 1000 1000 -- k w 2.0 5.0 fig.9 c ext external timing capacitor no limits pf 5.0 fig.9; note 3
1998 jul 08 7 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 dc characteristics for 74hct for the dc characteristics see 74hc/hct/hcu/hcmos logic family specifications . output capability: standard (except for nr ext /c ext ) i cc category: msi note to hct types the value of additional quiescent supply current ( d i cc ) for a unit load of 1 is given in the family specifications. to determine d i cc per input, multiply this value by the unit load coefficient shown in the table below. ac characteristics for 74hct gnd = 0 v; t r = t f = 6 ns; c l = 50 pf input unit load coefficient n a, nb 0.35 n r d 0.50 symbol parameter t amb ( c) unit test conditions 74hct v cc (v) waveforms/ notes + 25 - 40 to + 85 - 40 to + 125 min. typ. max. min. max. min. max. t phl / t plh propagation delay n a, nb to n q, nq 30 51 64 77 ns 4.5 c ext = 0 pf; r ext =5 k w t phl / t plh propagation delay n r d to nq, n q 26 48 60 72 ns 4.5 c ext = 0 pf; r ext =5 k w t thl / t tlh output transition time 7 15 19 22 ns 4.5 t w trigger pulse width n a = low 20 5 25 30 ns 4.5 fig.7 t w trigger pulse width nb = high 20 5 25 30 ns 4.5 fig.7 t w reset pulse width n r d = low 20 7 25 30 ns 4.5 fig.8 t w output pulse width nq = high n q = low 450 --m s 5.0 c ext = 100 nf; r ext = 10 k w ; figs 7 and 8 t w output pulse width nq = high n q = low 75 -- ns 5.0 c ext = 0 pf; r ext =5 k w ; note 1; figs 7 and 8 t rt retrigger time n a, nb 110 -- ns 5.0 c ext = 0 pf; r ext =5 k w ; note 2; fig.7 r ext external timing resistor 2 1000 -- k w 5.0 fig.9 c ext external timing capacitor no limits pf 5.0 fig.9; note 3
1998 jul 08 8 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 notes 1. for other r ext and c ext combinations see fig.9. if c ext > 10 pf, the next formula is valid: t w =k r ext c ext (typ.) where: t w = output pulse width in ns; r ext = external resistor in k w ;c ext = external capacitor in pf; k = constant = 0.45 for v cc = 5.0 v and 0.55 for v cc = 2.0 v. the inherent test jig and pin capacitance at pins 15 and 7 (nr ext /c ext ) is approximately 7 pf. 2. the time to retrigger the monostable multivibrator depends on the values of r ext and c ext . the output pulse width will only be extended when the time between the active-going edges of the trigger input pulses meets the minimum retrigger time. if c ext > 10 pf, the next formula (at v cc = 5.0 v) for the set-up time of a retrigger pulse is valid: t rt =30 + 0.19 r ext c ext 0.9 + 13 r ext 1.05 (typ.) where, t rt = retrigger time in ns; c ext = external capacitor in pf; r ext = external resistor in k w . the inherent test jig and pin capacitance at pins 15 and 7 (nr ext /c ext ) is 7 pf. 3. when the device is powered-up, initiate the device via a reset pulse, when c ext < 50 pf. ac waveforms fig.7 output pulse control using retrigger pulse; n r d = high. fig.8 output pulse control using reset input n r d ; n a = low.
1998 jul 08 9 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 fig.9 typical output pulse width as a function of the external capacitor values at v cc = 5.0 v and t amb =25 c. fig.10 typical k factor; external capacitance = 10 nf, external resistance = 10 k w to 100 k w and t amb =25 c.
1998 jul 08 10 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 application information power-up considerations when the monostable is powered-up it may produce an output pulse, with a pulse width defined by the values of r x and c x , this output pulse can be eliminated using the circuit shown in fig.11. power-down considerations a large capacitor (c x ) may cause problems when powering-down the monostable due to the energy stored in this capacitor. when a system containing this device is powered-down or a rapid decrease of v cc to zero occurs, the monostable may substain damage, due to the capacitor discharging through the input protection diodes. to avoid this possibility, use a damping diode (d x ) preferably a germanium or schottky-type diode able to withstand large current surges and connect as shown in fig.12. fig.11 power-up output pulse elimination circuit. fig.12 power-down protection circuit.
1998 jul 08 11 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 package outlines unit a max. 1 2 b 1 cee m h l references outline version european projection issue date iec jedec eiaj mm inches dimensions (inch dimensions are derived from the original mm dimensions) sot38-1 92-10-02 95-01-19 a min. a max. b max. w m e e 1 1.40 1.14 0.055 0.045 0.53 0.38 0.32 0.23 21.8 21.4 0.86 0.84 6.48 6.20 0.26 0.24 3.9 3.4 0.15 0.13 0.254 2.54 7.62 0.30 8.25 7.80 0.32 0.31 9.5 8.3 0.37 0.33 2.2 0.087 4.7 0.51 3.7 0.15 0.021 0.015 0.013 0.009 0.01 0.10 0.020 0.19 050g09 mo-001ae m h c (e ) 1 m e a l seating plane a 1 w m b 1 e d a 2 z 16 1 9 8 b e pin 1 index 0 5 10 mm scale note 1. plastic or metal protrusions of 0.25 mm maximum per side are not included. (1) (1) d (1) z dip16: plastic dual in-line package; 16 leads (300 mil); long body sot38-1
1998 jul 08 12 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 x w m q a a 1 a 2 b p d h e l p q detail x e z e c l v m a (a ) 3 a 8 9 1 16 y pin 1 index unit a max. a 1 a 2 a 3 b p cd (1) e (1) (1) eh e ll p qz y w v q references outline version european projection issue date iec jedec eiaj mm inches 1.75 0.25 0.10 1.45 1.25 0.25 0.49 0.36 0.25 0.19 10.0 9.8 4.0 3.8 1.27 6.2 5.8 0.7 0.6 0.7 0.3 8 0 o o 0.25 0.1 dimensions (inch dimensions are derived from the original mm dimensions) note 1. plastic or metal protrusions of 0.15 mm maximum per side are not included. 1.0 0.4 sot109-1 95-01-23 97-05-22 076e07s ms-012ac 0.069 0.010 0.004 0.057 0.049 0.01 0.019 0.014 0.0100 0.0075 0.39 0.38 0.16 0.15 0.050 1.05 0.041 0.244 0.228 0.028 0.020 0.028 0.012 0.01 0.25 0.01 0.004 0.039 0.016 0 2.5 5 mm scale so16: plastic small outline package; 16 leads; body width 3.9 mm sot109-1
1998 jul 08 13 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 soldering introduction there is no soldering method that is ideal for all ic packages. wave soldering is often preferred when through-hole and surface mounted components are mixed on one printed-circuit board. however, wave soldering is not always suitable for surface mounted ics, or for printed-circuits with high population densities. in these situations reflow soldering is often used. this text gives a very brief insight to a complex technology. a more in-depth account of soldering ics can be found in our data handbook ic26; integrated circuit packages (order code 9398 652 90011). dip s oldering by dipping or by wave the maximum permissible temperature of the solder is 260 c; solder at this temperature must not be in contact with the joint for more than 5 seconds. the total contact time of successive solder waves must not exceed 5 seconds. the device may be mounted up to the seating plane, but the temperature of the plastic body must not exceed the specified maximum storage temperature (t stg max ). if the printed-circuit board has been pre-heated, forced cooling may be necessary immediately after soldering to keep the temperature within the permissible limit. r epairing soldered joints apply a low voltage soldering iron (less than 24 v) to the lead(s) of the package, below the seating plane or not more than 2 mm above it. if the temperature of the soldering iron bit is less than 300 c it may remain in contact for up to 10 seconds. if the bit temperature is between 300 and 400 c, contact may be up to 5 seconds. so r eflow soldering reflow soldering techniques are suitable for all so packages. reflow soldering requires solder paste (a suspension of fine solder particles, flux and binding agent) to be applied to the printed-circuit board by screen printing, stencilling or pressure-syringe dispensing before package placement. several techniques exist for reflowing; for example, thermal conduction by heated belt. dwell times vary between 50 and 300 seconds depending on heating method. typical reflow temperatures range from 215 to 250 c. preheating is necessary to dry the paste and evaporate the binding agent. preheating duration: 45 minutes at 45 c. w ave soldering wave soldering techniques can be used for all so packages if the following conditions are observed: a double-wave (a turbulent wave with high upward pressure followed by a smooth laminar wave) soldering technique should be used. the longitudinal axis of the package footprint must be parallel to the solder flow. the package footprint must incorporate solder thieves at the downstream end. during placement and before soldering, the package must be fixed with a droplet of adhesive. the adhesive can be applied by screen printing, pin transfer or syringe dispensing. the package can be soldered after the adhesive is cured. maximum permissible solder temperature is 260 c, and maximum duration of package immersion in solder is 10 seconds, if cooled to less than 150 c within 6 seconds. typical dwell time is 4 seconds at 250 c. a mildly-activated flux will eliminate the need for removal of corrosive residues in most applications. r epairing soldered joints fix the component by first soldering two diagonally- opposite end leads. use only a low voltage soldering iron (less than 24 v) applied to the flat part of the lead. contact time must be limited to 10 seconds at up to 300 c. when using a dedicated tool, all other leads can be soldered in one operation within 2 to 5 seconds between 270 and 320 c.
1998 jul 08 14 philips semiconductors product speci?cation dual retriggerable monostable multivibrator with reset 74hc/hct423 definitions life support applications these products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. philips customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify philips for any damages resulting from such improper use or sale. data sheet status objective speci?cation this data sheet contains target or goal speci?cations for product development. preliminary speci?cation this data sheet contains preliminary data; supplementary data may be published later. product speci?cation this data sheet contains ?nal product speci?cations. limiting values limiting values given are in accordance with the absolute maximum rating system (iec 134). stress above one or more of the limiting values may cause permanent damage to the device. these are stress ratings only and operation of the device at these or at any other conditions above those given in the characteristics sections of the speci?cation is not implied. exposure to limiting values for extended periods may affect device reliability. application information where application information is given, it is advisory and does not form part of the speci?cation.

▲Up To Search▲

Price & Availability of 74HC423U

	To Download 74HC423U Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .