TEA2019 CURRENT MODE SWITCHING POWER SUPPLY CONTROL CIRCUIT DIRECT DRIVE OF THE EXTERNAL SWITCHING TRANSISTOR POSITIVE AND NEGATIVE OUTPUT CUR-

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1 CURRENT MODE SWITCHING POWER SUPPLY CONTROL CIRCUIT DIRECT DRIVE OF THE EXTERNAL SWITCHING TRANSISTOR POSITIVE AND NEGATIVE OUTPUT CUR- RENTS UP TO 05A CURRENT LIMITATION TRANSFORMER DEMAGNETIZATION AND POWER TRANSISTOR SATURATION SENS- ING FULL OVERLOAD AND SHORT-CIRCUIT PROTECTION PROPORTIONAL BASE CURRENT DRIVING LOW STANDBY CURRENT BEFORE START- ING (6mA) SYNCHRONIZATION CAPABILITY WITH IN- TERNAL PLL THERMAL PROTECTION Due o is curren mode regulaion, he TEA209 faciliaes design of power supplies wih following feaures : High sabiliy regulaion loop Auomaic inpu volage feed-forward in disconinuous mode fly-back Auomaic pulse-by-pulse curren limiaion Typical applicaions : Video Display Unis, TV ses, ypewriers, micro-compuers and indusrial applicaions For more deails, see applicaion noe AN406/059 DESCRIPTION The TEA209 is an 4-pin DIP low cos inegraed circui designed for he conrol of swich mode power supplies I has he same basic funcions as he TEA20Abu wih synchronizaion capabiliy by inernal PLL I is paricularly suiable for applicaions where oscillaor synchronizaion is required DIP 4 (Plasic package) ORDER CODE : TEA209 PIN CONNECTIONS OUTPUT 4 NEGATIVE SUPPLY (OUTPUT STAGE) AUXILIARY OUTPUT SUPPLY 2 3 SUBSTRATE POSITIVE SUPPLY VOLTAGE 3 2 I C SAMPLE (NEGATIVE) SATURATION SENSING 4 GROUND DEMAGNETIZATION SENSING 5 0 OSCILLATOR CAPACITOR ERROR AMPLIFIER NON-INVERTING INPUT 6 9 OSCILLATOR REFERENCE CURRENT SYNCHRONIZATION INPUT PLL OUTPUT 209-0EPS Augus 992 /

2 BLOCK DIAGRAM PHASE LOCKED LOOP OSCILLATOR V CC 0% DUTY CYCLE LIMITATION -V VOLTAGE LIMITATION I S V CC V AUX V Sampling Pulse Demagneizaion Sensing V CC SWITCH V REF = 24V Undervolage & S Q RECOPY & R FLIP FLOP Q DELAY 200ms THERMAL SHUT-DOWN 32V C omp a raor PLL Ou Sync R C Feed-back EPS x50 V REF TEA209 V CC good Bias I SENSE Ground V CE Monioring Subsrae V Oupu ABSOLUTE MAXIMUM RATINGS Symbol Parameer Value Uni V + CC Posiive Supply Volage 5 V V(aux) Auxiliary Oupu Supply Volage 5 V V CC Negaive Supply Volage 5 V IO (peak) Peak Oupu Curren (duy cycle < 5%) ± A I I Inpu Curren Pins 4-5 ± 5 ma Tj Juncion Temperaure 50 C T oper Operaing Ambien Temperaure Range 20, + 0 C T sg Sorage Temperaure Range 40, + 50 C 209-0TBL 2/

3 THERMAL DATA Symbol Parameer Value Uni Rh (j-a) Juncion-ambien Thermal Resisance 0 C/W ELECTRICAL OPERATING CHARACTERISTICS T amb =+25 o C, poenials referenced o ground (unless oherwise specified) Symbol Parameer Min Typ Max Uni V + CC Posiive Supply Volage 66 5 V V CC Negaive Supply Volage 3 5 V VCC(sar) Minimum posiive supply volage required for saring (V + CC rising) 6 66 V V CC(sop) Minimum posiive volage below which device sops operaing (V + CC falling) V V + CC Hyseresis on V + CC Threshold 0 6 V ICC(sb) Sandby Supply Curren Before Saring [V + CC <VCC(sar)] 6 ma V h (Ic) Curren Limiaion Threshold Volage (pin 2) mv R (Ic) Collecor Curren Sensing Inpu Resisance 000 Ω I S Demagneizaion Sensing Threshold mv Demagneizaion Sensing Inpu Curren (pin 5 grounded) µa τmax Maximum Duy Cycle 0 0 % A V Error Amplifier Gain 50 I + I Error Amplifier Inpu Curren (non-invering inpu) (pin 6) 2 µa V (REF) Inernal Reference Volage V V(REF) T Reference Volage Temperaure Drif 0 4 V/ C T OSC Oscillaor Free-running Period ( R = 59kΩ, C = 5nF) µs f OSC T Oscillaor Frequency Drif wih Temperaure (V + CC = + V) 005 %/ C fosc V CC Oscillaor Frequency Drif wih V + CC (+ V < V + CC < + 4V) 05 %/V on(min) Minimum Conducing Time (C = nf) 2 µs SYNCHRONIZATION INPUT (pin ) Symbol Parameer Min Typ Max Uni V pp Peak o Peak Sawooh Volage V R () Inpu Impedance 20 kω PLL CHARACTERISTICS (see Tes Circui) Symbol Parameer Min Typ Max Uni Frequency Sensiiviy 00 Hz/µA T Capure Range (T OSC =64µsTyp) T OSC -T SYN min µs T SYN max -T OSC µs SATURATION SENSING (pin 4) Symbol Parameer Min Typ Max Uni V (4) Inpu Threshold 32 V I (4) Inpu Curren (V 4 > 32V) 50 µa Inpu Inernal Resisance kω RECOMMENDED OPERATING CONDITIONS Symbol Parameer Min Typ Max Uni V + CC Posiive Supply Volage V VCC Negaive Supply Volage 3 V I O Oupu Curren 05 A Foper Operaing Frequency 30 khz 209-0TBL TBL TBL TBL TBL TBL 3/

4 TYPICAL CIRCUIT V6 V5 V3 40Ω 0Ω 0nF AS 2kΩ 4µF 0nF kΩ TEA209 RAMP GENERATOR IC 0V V 56kΩ 59kΩ % 4µF 39kΩ 33nF 5nF 00Ω 4nF V0 V2 V EPS GENERAL DESCRIPTION (see applicaion noe AN406/059) Figure : Curren Mode Conrol Operaing Principles (Figure ) On every period, he beginning of he conducion ime of he ransisor is riggered by he fall of he oscillaor saw-ooh which acs as clock signal The period T osc is given by : Tosc 069 C (R ) (T osc in seconds, C in Farad, R in Ω) The end of he conducion ime is deermined by a signal issued from comparing he following signals a) he sawooh waveform represening he collecor curren of he swiching ransisor, sampled across he emier shun resisor b) he oupu of he error amplifier V REF ERROR AMPLIFIER ERROR SIGNAL OSCILLATOR COMPARATOR Re SENSE FLIP-FLOP S R Q V i OUTPUT FILTER LOAD Base Drive Fas urn-on On each period, a curren pulse ensures fas ransisor swich-on This pulse performs also he on(min) funcion a he beginning of he conducion Proporional base drive In order o save power, he posiive base curren afer he saring pulse becomes an image of he collecor curren The raio is programmed as follows (Figure 2) = R B R E OSCILLATOR SAWTOOTH (sample) FLIP-FLOP OUTPUT Error Signal EPS / EPS 4/

5 Efficien and fas swich-off When he posiive base drive is removed, s (ypically) will elapse before he applicaion of negaive curren herefore allowing a safe and rapid collecor curren fall Safey Funcions Overload & shor-circui proecion When he volage applied o pin 2 exceeds he curren limiaion hershold volage [Vh(Ic)], he oupu flip-flop is rese and he ransisor is urned off The shun resisor R e mus be calculaed so as o obain he curren limiaion hreshold on pin 2 a he maximum allowable collecor curren Figure 2 Demagneizaion sensing This funcion disables any new conducion cycle of he ransisor as long as he core is no compleely demagneized When no used, pin 5 mus be grounded on(max) Ouside he regulaion area and in he absence of curren limiaion, he maximum conducion ime is se a abou 0% of he period on(min) A minimum conducing ime is ensured during each period (see Figure 2) Supply volage monioring The TEA209 will sop operaingif V CC +onpin3 falls below he hreshold level VCC(sop) COLLECTOR CURRENT 0 on(min) TEA209 R B BIAS CURRENT R B 2 R e 0 R e EPS Saring Process (Figure 3) Prior o saring, a low curren is drawn from he high volage source hrough a high value resisor This curren charges he power supply sorage capacior of he device No oupu pulses are available before he volage on pin 3 has reached he hreshold level [V CC(sar), V + CC rising] During his ime he TEA209 draws only ma (ypically) When he volage on pin 3 reaches his hreshold base drive pulses appear The energy drawn by hese pulses ends o discharge he power supply sorage capacior However a hyseresis of abou V (ypically) ( V CC ) is implemened o avoid he device from sopping Figure 3 : Normal TEA209 Sar up Sequence 6V 49V V CC V CC (sar) V CC V CC (sop) 209-0EPS 5/

6 The TEA209 has some addiional capabiliies compared o he TEA20A : The oscillaor charge curren is supplied hrough an inernal curren generaor,programmed exernally - insead of using an exernal charging resisor The sawooh so obained is linear The oscillaor can be synchronized hrough an inernal PLL circui This feaure provides synchronizaion beween he exernal sync pulse and he end of he swiching ransisor curren The sync pulse can be for example he fly-back pulse of a TV horizonal sweep circui As indicaed in he applicaion diagram, his pulse is applied firs o a RC nework o obain a low volage sawooh and hen o pin of he circui The PLL oupu (pin ) supplies a correcion curren o pin 9 hrough an exernal resisor, so as o mainain he oscillaor a he correc frequency (refer o applicaion noe AN406/059 for deailed informaion) In he TEA209, he power supply of he posiive oupu sage is separaed from he main power supply, so ha i can be supplied from a lower volage in order o reduce he IC power dissipaion For low power applicaions, he circui can be normally supplied by connecing pins 2 and 3 ogeher In order o proec he subsrae (pin 3) from he parasiic volage peaks produced by negaive oupu curren peaks a pin 4, he subsrae (pin 3) is inernally separaed from he negaive supply (pin 4) They mus be exernally conneced ogeher The swiching ransisor sauraion volage can be moniored a pin 4 To achieve his, a high volage diode mus be conneced beween he collecor of he swiching ransisor and pin 4 Also a resisor mus be conneced from pin 4 o V + CC (see applicaion diagram) This arrangemen is useful when he chosen value of base curren is very low and as a consequence he sauraionvolage will be high In hiseven, when VCE(sa) increases above 25V, he base curren is inerruped before he normal end of he period Remark : he TEA209 can also operae wihou his proecion TYPICAL APPLICATION 4 x N400 4µF 35V Sync Pulse N44 Ω 39Ω N44 n3 n BYT-00 00µF 60V 20V 04A RF Filer 2 x 2mH 0µF 0µF Mains Inpu 05A 2kΩ 4nF C2 33nF 0kΩ kω 56kΩ 0µF 0kΩ 0kΩ kΩ 5nF TEA µF 0Ω 2 20kΩ W 3 4 BYT -00 BYT-00 33Ω 00Ω BUV 46A BYT Ω kω 3W n0 60Ω 3W BYT-00 n2 24V 05A 40µF 40V 39kΩ 33nF 4Ω 0µF PMAX = 60W Free-running Frequency : 5kHz 55VRMS V AC 250V RMS 3 x N400 Oupus: 20V ± 3%, 04A VCE 24V ±3%, 05A Monioring Primary Ground Secondary Ground 209-0EPS 6/

7 PACKAGE MECHANICAL DATA 4 PINS - PLASTIC DIP a I L b Z b e3 B e Z E D 4 F PM-DIP4EPS Dimensions Millimeers Inches Min Typ Max Min Typ Max a B b b D 20 0 E e e F 020 i L Z DIP4TBL Informaion furnished is believed o be accurae and reliable However, SGS-THOMSON Microelecronics assumes no responsibiliy for he consequences of use of such informaion nor for any infringemen of paens or oher righs of hird paries which may resul from is use No licence is graned by implicaion or oherwise under any paen or paen righs of SGS-THOMSON Microelecronics Specificaions menioned in his publicaion are subjec o change wihou noice This publicaion supersedes and replaces all informaion previously supplied SGS-THOMSON Microelecronics producs are no auhorized for use as criical componens in life suppor devices or sysems wihou express wrien approval of SGS-THOMSON Microelecronics 994 SGS-THOMSON Microelecronics - All Righs Reserved Purchase of I 2 C Componens of SGS-THOMSON Microelecronics, conveys a license under he Philips I 2 C Paen Righs o use hese componens in a I 2 C sysem, is graned provided ha he sysem conforms o he I 2 C Sandard Specificaions as defined by Philips SGS-THOMSON Microelecronics GROUP OF COMPANIES Ausralia - Brazil - China - France - Germany - Hong Kong - Ialy - Japan - Korea - Malaysia - Mala - Morocco The Neherlands - Singapore - Spain - Sweden - Swizerland - Taiwan - Thailand - Unied Kingdom - USA /

Obsolete Product(s) - Obsolete Product(s)

Obsolete Product(s) - Obsolete Product(s) DUAL SWITCH-MODE SOLENOID DRIER HIGH CURRENT CAPABILITY (up o.5a per channel) HIGH OLTAGE OPERATI (up o 46 for power sage) HIGH EFFICIENCY SWITCHMODE OPERATI REGULATED OUTPUT CURRENT (adjusable) FEW EXTERNAL