FX101L

FX101L CMLMICRO | Alldatasheet

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— PRODUCT INFORMATION Obsolete Product - For Information Only - MULTI-PURPOSE FREQUENCY SENSITIVE SWITCH GENERAL DESCRIPTION FX 0 The FX-101L is.a high performance frequency sensitive switch 1 1 L constructed in monolithic form using MOS/MSI techniques. It hat SeidiibieG- bude cmon exit is a pin and function compatible equivalent of the standard ——ESFEE EO e—vorverv CML FX-101, but offers improved accuracy and operates from = ~ lower voltage supplies. The FX-101L is the preferred version for ae ws new equipment and systems in the course of planning, and in mg [PTT Ten en y many cases can be employed as a direct plug-in replacement for ° 1 : F—\\ any the FX-101 in existing applications. ig al SLSR 7 Le} yet The FX-101L accepts sinewave or pulse input signals and oper- by - | |_[ass ates an integral semiconductor switch when the input frequency ee = i { a8 | [9 1 fe reaches an accurately predetermined value. By simply ground- t — ' ing or ‘floating’ a control input pin the FX-101L may be arrang- i one) tis ‘Afsepeayt |i ed to switch ‘ON’ when the input frequency lies anywhere above Wt F si 4 ee ' a single datum value (Datum Mode) or, alternatively, within a erage I D4 preset band of values (Band Mode). The switch set points may | = ee TTT be varied over a wide range of frequencies according to the ert" oT values of two external resistors and two capacitors. Set point “ “y stability is of a high order and is maintained over the entire specified range of supply voltages and operating temperatures. _ in the latch mode. Further facilities include, direct switch reset, Set point thresholds are extremely sharp and yield an effective and selection of Fail Safe (switch OFF), delayed Fail Safe or ‘Q’ factor exceeding 1,000; the FX-101L also exhibits a fast Ignore (hold state) switching options in the event of signal int- response time combined with exceptional immunity to turn-on _erruption. Function control inputs are high impedance and may by random signal noise. be operated by external logic levels. In addition to the Datum/Band functions the FX-101L has | The FX-101L is housed in a 10 lead TO-100|style package and control inputs which allow a choice of ‘Latch or Unlatched’ —_ operates from a single|wide tolerance D.C. supply of — 8V to — switch operation, which includes ‘Latch to on’ or ‘Latch to off’ 15V, over the extended temperature range. OUTSTANDING FEATURES @ =DATUM OR BAND SWITCHING @ NARROW BAND/WIDE BAND SWITCHING @ ADJUSTABLE SWITCH FREQUENCIES @ SINE OR PULSE SIGNAL INPUT ‘@ HIGH STABILITY SET POINTS. @ SWITCH LATCHING OPTIONS FIG2 _FX-101L_SWITCH STATE vs INPUT FREQUENCY TO-100: STYLE ‘PACKAGE FIG3 kee 2 8 10 Leads 0-038 dia " 38 P ---- — — — Steet % 8° by 0-515" long. 3) 0 Equispaced on 023° PCD 24% Setpoint 12 - = VIEW ON PINS ole time : \\ ! ' PIN_DATA ‘ ' \\ ' 1. SIGNAL INPUT 6. +VE SUPPLY \\ \\ 2. SIGNAL FAILURE RECOGNITION 7. -VE SUPPLY Peso sw roaNG KY WN 3. LATCH FUNCTIONS 8. SET ft j ‘ 4, SWITCH OUTPUT Not 9. MODE SELECTOR LON 5. SWITCH OUTPUT No2 10. SET £2 Pi barn DE \\\\\\ Note: Pin6 is internally connected to the case.

OPERATING PRINCIPLE Latch to OFF mode is obtained by open-circuiting pin 3 whilst the switch is in the ON condition, Open-circuiting the pin has no direct The tone recognition system employed by the FX-101L is based ona effect on the switch state, but if the switch is subsequently turned OFF Period sampling technique. Input signals are amplified and shaped to by the signal frequency it will latch in the OFF state, e.g. it will not turn provide clock signals to the bistable flip-flop, the output of which isa ON again when the signal frequency reverts to an ON value. square wave having a period equal to the interval between successive in- ; put waveform ‘zero-crossings’. To reset the switch, the frequency must be returned to an ON value and . - pin 3 momentarily grounded. It is only necessary to ground the pin for The flip-flop output triggers a monostable (M1) which generates a ref- 3 Deriod equal to the device response time, it may then be open-circuited erence period corresponding to_1_, where f1 (Hz) represents the Datum ‘again ready fora further latch action. tT mode set-point, or the upper edge of the Band mode tone accept chan- _To obtain the Latch to ON function, pin 3 must be grounded (logic ‘O") nel. At the expiry of M1 period, monostable M2 is triggered; the summed and adiode connected between pins 4 and 8 as shown in Fig.4. If a load periods M1 + M2 corresponding to_1_, the lower edge of the tone accept _is also connected to pin 4, the load current should be such that the maxi- channel. 12 mum ‘0’ level (switch ON) at pin 4 is -2v. To reset the Latch, the signal i A canal j ‘od i must first be returned to an OFF value, or zero, and the diode fink The reference periods are compared against the signal input period in 2 momentarily broken. As an alternative to breaking the link, the diode comparator, the output of which controls a special counter/storage hay be reverse biased by momentarily connecting pin 4 to VDD (-ve) system. This counting system discriminates against random spurious ia g 470.2. limiting resistor. information and delivers an output only when a number of sampled periods have a true average value falling within the ‘tone accept’ limits. The output of the counter system, which is continuously monitoring the moe maura Takes Tmo input information, is applied to the output buffer switches. Gating Pasian ianeuerne pe circuits are incorporated which prevent false operation when harmonics | alton | auteur cova. Youur carom | of the tone frequency are applied. Loo: ee. out ruvcnions | This unique and patented tone recognition system yields extremely Loe | aa | sharp tone channel definition, coupled with a fast response time and : [eeeers | fe | cuaroes | high immunity to false turn-on due to outband noise, regardless of the eerweenni ea “ | noise frequency and amplitude, The period sampling system requires, carl swminwe can, if mixed with the required inband tone, prevent the circuit from , recognising that the tone is present. This effect is produced because the ‘sees | Larenro ov | noise ‘jitters’ the interval between successive signal zero-crossings and ODO the comparator/counter rejects the information as not being consistent with an input signal having a frequency actively within the tone channel Lost Vs ePEN CIRCUIT LOG = NE SUPPLY eaCLNO! limits. If the noise is random in nature, e.g. spurious noise spikes or short term OUTPUT SWITCH CHARACTERISTICS interference (short in relation to the device recognition time, or inband The standard output switches used in the FX-101L are MOS driver tran- tone duration) it will have little or no effect other than possibly to in: sistors connected between each output pin and the ground pin (+ve). No crease the overall tone recognition time by a few cycles. If the noise is internal load is provided, therefore the only potentials present any out- continuous, e.g. parallel inband and outband tones are on the signal line Pin oe tno Po vided by the external losd. Low current lose say simultaneously, the device will not recognise the inband tone. If the Be directly connected between the output pin and -ve supply, high noise is semi-continuous, e.g. speech signals, increasing the inband tone Crent loads should be operated through a buffer transistor. duration will allow the tone to be recognised during a momentary ‘noise’ pause, When the switch is turned ON, it becomes a low resistance path (value one i i z A = R’on) connecting the output pin to ground, (see Fig.5). When the The device is therefore ideal for use when inband tones are transmitted switch ig turned OFF, it exhibits a high resistance (10M { minimum), individually, or sequentially, but operation in parallel-tone signalling a ttectively open-circuiting the output pin. The switch has a ‘jitter-free’ Schemes is not recommended, unless adequate pre-filtering is used, snap action; typical OFF-ON transition times are in the order of 2 micro-seconds. GENERAL CIRCUIT OPERATION STANOARO_OUTEUT_ SWITCH -“EOIVALENT_ciRUIT —_ASSOCUTED_ouTPUT_LeveLs Fig, 2 illustrates the switching functions performed by the FX-101L. “ore! The relationship between the signal input frequency and the output See “eee tied switch state is shown for Band and Datum operating modes. Two in-phase Ea i i switches are provided. The logic level applied to pin 9, the mode selector (exrennat soo input, determines which operating mode is obtained, the logic truth { Vone YOO.” table is shown in fig. 4. au (S] When Band mode is selected, signal frequencies lying within the limits a ‘igniat f1 to £2 will turn the output switches ON; signals lying ‘outband’, either ba on above f1 or below £2, will turn the switches OFF. 4 ens, OF oy ‘oe [vou If Datum mode is used, signal frequencies higher than set-point f1 turn ; the switches ON and signals below f1 turn the switches OFF. Note that ie te eaves set-point £2 is inactive when Datum mode is in use, but components R2/C2 must still be fitted to ensure correct operation of the circuit. A convenient rule in these circumstances is to make {2 a ‘ghost’ value at a IMPORTANT: The exty potentais present ot any output pin ries nominal 10% below f1 (see also the notes on Response Time). so, See aod eae te Seraa fod. Set-point ‘definition’, i.e. hysterisis, is extremely sharp; values of 0.1% SUPPLY NOTES of set-point frequency are typical. > | References to ground, logic ‘O" and logic ‘I’ in this data sheet are based ‘Signal Failure’ recognition facility is incorporated in the circuit which on the use of a grounded positive supply, i.e. HT (VDD) is negative. A allows 2 choice of switch actions in the event that the input signals are jogic ‘I’ level is therefore near VDD (-ve) anda logic ‘O’ level near ground cut-off instantaneously. (See notes on Signal Failure Recognition). (+ve). There is, however, no objection to operation with the -ve supply Fig. 4 shows the latching options available by applying logic levels to ——_ grounded, but reference to logic polarities remain unchanged, i.e. a logic pin 3, ‘I is always -ve with respect to a logic ‘O'. Grounding pin 3 enables the switch to work in the ‘unlatched’ mode; in Example: a) Vpp= -12. +ve = ground this mode the switch turns ON & OFF according to the input frequencies logic ‘I’ = -12V and logic ‘0’ = ground. applied, and the switch therefore reflects the current relationship bet- b) Vop © OV fw = +12V ween the signal frequency and the set-point frequencies. MoO Sy endtogkeOr e+ 12V

Note also that the case is internally connected to the +ve pin and will If the input signal changes instantly from inband to OHz, 0.9. 10 cycles therefore be above ground potential if VDD = OV. It is also important _of outband signals are not received, a modified response time Trg will to ensure that no pin receives a potential which is positive with respect _elapse before the outputs switch to the OFF state. to the +ve supply pin. Failure to observe this rule may result in damage to the device. SIGNAL FAILURE RECOGNITION (TFs) As the FX-101L is essentially a digital device the internal circuits come SIGNAL INPUT NOTES to rest when no input signals are present, If an instantaneous signal cut The FX-101L incorporates a signal input amplifier offering a high input Off occurs while the switch is in the ON state it will remain ON until a impedance. The amplifier is designed using negative feedback principles _S!9nal which turns it OFF is received. In applications where the signal is and therefore the input is D.C. self-biased. Signals to the input pin 9 OMtinuously variable value, any absence of signals is usually preceded should normally be A.C. coupled to avoid disturbing this bias point, PY. frequency run-down through a set-point and the switch is therefore High level pulse signals (> -6V) may be directly coupled, The actual OFF when signals cease. in some applications, however, an OFF value shape of the signal waveform is not important and may be sine, square ‘Signal may not always be available and the input to pin 2 provides or pulse in form, facilities for automatic ‘no signal/no OFF signal’ turn-off. Input impedance is typically 50k Q at mid-range supply voltages. This With pin 2connected to ground (+ve), the switch ignores signal interrup- value varies with supply voltage and production tolerances, and a total _‘tions and will turn ON or OFF only in response to defined input signal spread of 25k @ to 200k Q shouldbe assumed. The minimum value of _‘frequencies. the input coupling capacitor (C’in) depends on the frequency of set- To obtain automatic switch to OFF, should input signals fail, pin 2 Point f'2 and must be large enough to yield a time constant product: should be connected to a CR network (C’x, R’x) as shown in Fig. 7, If Cinx Zin(MFDxMa) > —1 the output switches are ON and input signals are cut-off, the capacitor * Fhe) charges to a preset level which forces the output switches to OFF, The Fig. 6 shows the production spread of input signal sensitivity versus °P2citor is then automatically discharged. The Signal Failure Recog- supply voltage. If overvoltages and trarisients are likely to occur on the _ition time TFg (Fig.7) can be adjusted to allow planned signal breaks signal line, a protective diode clamp should be used to limit input volt. _t© be ignored, but ensures that the switch adopts the OFF state if a true ages to the maximum permitted levels, signal failure occurs. For general purpose applications @ convenient value for Teg is —10__ Q pu ppl Fs is sep ; seconds, which yields a period Tg approximately equal to the normal FOG SONAL SENSITIVITY verevs SUPPLY VOLTAGE. response time Tg. Whilst Teg can be set to almost any required longer delay time, it should never be made less than___2__ seconds: if it is too Signal Input ¥2 (Hz) pe CIN=O1HFD (nominal waive) short, the interval between successive input signal samples may be mis- [ | [¥ ‘signe! [input taken for ‘LO Signal’ and the output switches will be held permanently 200 Tee i Bae OFF. reo ‘Seager 2 To maintain Trg accuracy, R’x is limited to the range 100k Qto 500kQ. 160 = This is due to an interna! pull-up resistor on pin 2, which shunts R’x and xo modifies its effective value. This internal resistor has a nominal value of

6 TyPIcaL 4M Q_, but this is subject to production tolerances and also varies with

m0 supply voltage. ba = ee Pin 2 may also be used as a Direct Reset which switches the outputs to * — the OFF state, over-riding the input signal. If pin 2 is open-circuited, the internal pull-up resistor applies a reset voltage to the output switch ry " oes ee stages. This resets the switches to an OFF state in a maximum time eee 7b seconds. Note that the output switches will be held permanently a ae ee ie ort ° ee CF Ff pin 2'is accidentally left open-circuit. SUPPLY. VOLTAGE SWITCH RESPONSE TIME (Ts) The response time (Tg) of the FX-101L is defined as the interval between Far _switon nesense _Tiwes the input frequency crossing a set-point threshold and the output switches changing state. This interval is normally equal to approximately Se 10 vycles of the input treaveney (22 but this will be increased if the Maer. iioss So ate reg see rin ve frequency difference between set-points 1 and £2 exceed 2:1, e.g. Band- ote nox ie som width (BW) > 50%, toma 2 ime jeer Response time may also be increased if random noise impulses are super- er as ns ena Oe imposed on the input signals. ‘aiid aro’ READ tine: Excluding input noise effects, response time is expressed: o meses : i Le ioe 10 t 4 t Ts (min) & Fy (Hay Seconds, where {1 < 242 AE d ‘ } d Ts (max) a4 = Seconds, where f1 > 242 eee ucn: Ba as a The frequency of set-point f2 should be taken into account regardless of Fcctelogion aaron | : i ; whether it is an operating set-point, as in Band Mode, or a ‘ghost’ set- 1 prooalln Glencae ee ee Point, as in: Datum Mode. 4 3208, (ORL HO) ° Redlegs Cm TSeRESPONGE TNE FSeSIOML FALE RECOOWTION THE Fig. 7 shows the effect of response time Tg when the input signal changes from outband to inband and vice-versa, as in FSK signalling. The same characteristics apply when signals change from Low to High using Datum Mode. From this it is seen that Ts is a constant factor for frequency shifts in either direction, provided not less than 10 cycles of input signal are received after the frequency crosses a set-point threshold.

SET-POINTS F1 & F2 Fig, 2 illustrates the frequency relationships between f1 and 2. Set-point 1 is always at a higher frequency than £2 and is defined simply by com- ponents R1/C1, set-point 2 is defined partly by R1/C1 and partly by R2/C2. The relationship between set-point frequency and the compon- ent values are given by: 1 1 (4) OT Ro y 0.7 §(Hz) Where for f1, RC=R1x C1 (M& x MFD) andfor 2, RC=(R1x C1) +(R2x C2) The factor 0.7 is a design constant and is subject to production toler- ances of +5% maximum. When operating in Band Mode, the inband signal channel bandwidth (BW) is defined as the frequency of f2 expressed as a percentage below f1, i.e, f1 = 100Hz, f2 = 90Hz, BW = 10%. Note that BW refers to total bandwidth not a plus or minus value about centreband. Subject to the set-points lying within the specified frequency limits, the maximum BW permitted is 99%, i.e. frequency ratio f1 to £2 of 100:1. The minimum BW achievable is determined by practical limitations on the ratio of R1.C1 to R2, C2; using the minimum recommended values for R2, C2, bandwidths of 1% and upwards are obtainable depending on operating frequencies. When operating narrow-band, it is important to keep the value of C2 as large as possible by using the lowest permitted values for R2. This minimises the effects of stray wiring capacities, because if these capacities are large in relation to C2, set-point stability will suffer. When operating in Datum mode, a convenient method of setting f2 toa ‘ghost’ value about 10% below f1 is to make R1 = R2 and C2 nominally one tenth the value of C1, Alternatively minimum spec- ified values may be fitted for R2 C2, regardless of the values used for R1 C1. The exact setting of the ‘ghost’ 2 has no effect on f1 stability; it only becomes important when it is very much lower than f1 and may therefore, influence the response time of the switches. To choose a set of values, first calculate the C/R product for f1 and select those component values for R1/C1. Calculate the C/R product for 12, subtract from this the product already obtained for f1 and select values for R2/C2 which yield the product difference. To adjust set-point frequencies and to allow adjustment for component tolerances, R1 and R2 may each consist of a fixed resistor in series with a variable resistor (see Fig.8). For maximum stability, the variable section should form only a small fraction of the total resistance. For maximum set-point stability, good quality components should always be used; metal oxide resistors and polystyrene/polycarbonate capacitors are suggested. FIG.6 _SET-POINT FREQUENCY COMPONENTS “ve VE 4 ERY ev Components Comporients associated AY a associated with with setpoint R R set-point 12 PIN PIN Gi C2 WES a Ne RECOMMENDED COMPONENT LIMITS RI &R2, 100Kamin, no maximum limits : C1, 470pf min. O-SMFD mox C2, 100pF min, OSMED max. :

BASIC TONE OPERATED SWITCH, FIGS aE is OK? | BRNO mm Ba as 2 5 (c fer. Feson 6 ‘5v ream] TT JO ‘SIGNAL, i oe 33007] Omer [3300p¢ ney ot Fig. 9 shows the basic circuit arrangement for Band mode tone operated switching, and illustrates two different methods of interfacing an output switch to TTL togic elements. When the FX-101L output is ON, the out- put of interface (1) is at TTL logic ‘O’ and the output of interface (2) at logic ‘I’. With the component values given, the FX-101L output turns ON for an input tone of 1700Hz nominal (#1 = 1800Hz, f2 = 1600H2), the typical recognition time (Ts) being 6mS. When the inband tone is cut-off, the switch turns OFF in 0.6 R’x C’x seconds (Tp), which for the compon- ents specified is nominally equal to Ts at 6mS. If turn-offiseffectedby changing the inband frequency to an outband value, e.g. FSK operation, the turn-off time is 10 seconds, where f is the outband tone frequency. f (Hz) By substituting suitable values for R1/C1, R2/C2 and R’x/C’x, operation at alternative tone frequencies is readily obtained. VOICE OPERATED SWITCH nee a oe Eo GP tet Oo Se y Sey P ay = we Be =a switcy ert “ow H or eure Fig. 10 shows the FX-101L arranged as a Voice Operated Switch, e.g. wideband frequency detector. Voice signals having frequencies lying between 160Hz (f2) and 3kHz (f1) turn the switch ON; when input signals cease for a specified minimum period of time, the switch turns OFF. This signal break recognition time is 2.8 seconds using the R’x/C'x values listed, other values may be used to obtain different ‘dwell-over’ times. If signals lying outside the voice band are applied, they may cause the switch to turn OFF prematurely (_10 _ & 60mS); input signals #2 (Hz) outside the 160 Hz ——> 3kHz band should therefore be limited. The ‘voice detect’ switching time Tg is in the region 30 to 60mS, according to the initial frequencies present. In this example the output switch operates a relay via a transistor driver. Note the surge suppression diode which must always be fitted with inductive loads. Other switching arrangements may be employed as required, e.g. semiconductor squelch switch,

Max, voltage between any pin and positive supply pin —20V & +0.3V _ Operating Temperature Range —30°C to +85°C Storage Temperature Range —55°C to +125°C Max. Output Switch load current —10mA each Max. ‘Device Dissipation (at 25°C T’amb) 400mW CHARACTERISTICS (T’amb = 20°C, VDD = —12V *2Vv, Set-point frequencies 10Hz to 3kHz unless specified) Symb] Parameter] Gonditons & Notes [win [Tye wax] Uni Vpp | SUPPLY VOLTAGE Operating Range [-8 |-12|-18 | Vv | Ipp_| SUPPLY CURRENT Total, excluding switch load current | [25] [ma] j SIGNAL AMPLITUDE Sine or Pulse input signals, OHz to 100kHz, V vin RANGE A.C. Coupled. Input impedance typically 50k2 pk-pk| ADJUSTMENT LIMITS Max & Min Set-Point frequencies THz[[20kHz[ | hy FREQUENCY RATIO Permitted ratio adjustment, f2 percentage below f1 ee SET-POINT DEFINITION | Individual set-point on/off differential as % oF nomina set-point frequency. Af Set-point deviation versus supply Supply a a SET-POINT STABILITY | volts & T’amb. External components Ts RESPONSE TIME Overall switching time following receipt of @3kHz [ [33 [| ‘switch’ value frequency. @s00nz[ | 20{ R’on | SWITCH ‘ON’ Internal resistance between output pin and ground, 03 KQ RESISTANCE switch ‘ON’ (Switch ‘OFF’ resistance >10M & ) . EACH SWITCH) 1" LOGIC HIGH External logic levels to control inputs (Internal |-6 | [-15 | v | ‘oO’ LOGIC LOW 300k pull-up resistors give logic ‘I’ when pin O/C) 0 V PRINTED CIRCUIT BOARD C-013L ‘ fon _cincuir_oigotam 019. The C-013L printed cifcuit card is designed to assist engineers in rapidly "VEO oe and correctly assembling-a fully functional frequency operated switch : s module. Supplied ready punched and with component positions clearly Be Hk me ek ‘ marked, they are suitable for experimental work or as short run produc- ue | gen bara aaa) tion P.C.B.'s. Omerly | fe ea Manufactured from 1/16” S.R.B.P. with tinned copper conductors, it let | measures 4” (103mm) x 3” (76mm). Card connections are shown by er 8 i printed letter code, The cards are supplied complete with a set of press- eigen bg bo in terminal posts for mounting those components most likely to be ef °, P | oe ening changed during experiments, thus minimising possible damage to the Oo Se 3 wot IO metal tracks. Components are not supplied. Connection to the card may , Be f, 4 % b cs be made by direct wiring or by edge connectors, using a 12 way 0.15” | a pitch P.C.B, socket. Normally, the FX-101L is soldered directly into ° Position, but a 10 pin TO-100 style socket may be used if required, By BEG: ae CIRCUIT DESCRIPTION C-013L ES et of Ls Supplies are connected to terminals M (-ve) and G (+ve). Two output ee t terminals, L & J, are provided. Either or both may be used, directly or via transistor drivers, according to the links/components fitted. Low ON is used. Connecting terminal A to G gives Datum mode operation, current loads up to -10mA, can be connected directly between the out- _leaving A disconnected gives Band mode. Input signals are applied to put and M, and links (1) or (2) fitted as appropriate. High current loads, _ terminal C. if high voltage spikes can appear on the signal line, protec- up to 200mA, are connected between the output and G, in which case _tive diodes D1/D2 should be fitted and a 10k $2 resistor used for Rin, T1/2 and R3 through R6 should be fitted and links (1) and (2) removed. _If no protection is required, R’in may be a wire link. Link 3 allows pin 3 to be permanently grounded, giving the ‘Unlatched’ _If C’x is omitted, a wire link must be fitted in its place. operating mode. Alternatively, linking D to G via a N/O push-button P gives Latch to OFF mode, push button to unlatch. som ree Miopdienat 4N914 or stmntter Diode D3 is fitted if Latch to ON is required. To unlatch, momentarily RV 1 Plessey type WMP or similar. connect E to Musing a push-button, Link (3) must be fitted if Latchto TR + TO-5 silicon NPN rating to suit load.