 the open container causing an unpleasant and possibly harmful odor.
U.S. Pat. No. 4,391,689 issued to Golias on July 5, 1983 shows an automated electrophoresis and staining apparatus for processing a gel attached to a MYLAR (trademark) sample plate. The sample plate with the gel attached is frictionally supported within a plate holder rack. Gels used in such an apparatus are extremely thin, of the order of a few microns. Such an apparatus is unsuitable for processing gels having a thickness of the order of about 0.4 mm to about 3.0 mm which are not bound to a supportive backing.
U.S. Pat. No. 3,930,880 issued to Hoefer on Jan. 6, 1976 discloses a slab gel diffusion destainer for gels having a thickness in the millimeter range. Subsequent to electrophoresis and staining, the slab gel is supported on a flexible mesh which contacts the slab gel on both sides. The mesh is rolled into a cylindrical form and inserted into a slab holding tube and confined therein by placing end caps on each end of the tube. The tube is disposed within a cylindrical container and a suitable washing liquid is circulated through the interior of the destainer. A problem with this apparatus is that rolling the slab gel in the mesh tends to damage or distort the slab gel. Furthermore, diffusion of the stain into the overlapped portion of the gel can be non-uniform.
With the exception of the destainer described in the above-referenced U.S. Pat. No. 4,357,174, the apparatus described herein are expensive and not well suited for the handling of slab gels. The present invention relates to an output stage for a voltage regulator or other type of circuit which must conduct load current at both low and high input/output voltage differentials. More particularly, the present invention relates to a circuit for distributing load current among multiple power transistors, each optimized to conduct current over a different range of input/output voltage differentials.
Power devices, such as voltage regulators and power switches, which often must supply current to a load while operating at a high input/output voltage differential, require an output stage power transistor that can conduct substantial load current at such high voltage differentials without creating a risk of destroying the power transistor due to thermal instabilities and overheating in localized areas of the transistor. To prevent the power transistor from becoming damaged in this fashion, ballast resistors are used in the emitter of the power transistor to stabilize the current in the
the open container causing an unpleasant and possibly harmful odor. 
 U.S. Pat. No. 4,391,689 issue to Golias on July 5, 1983 usher an automated electrophoresis and staining apparatus for processing a gelatin attached to a MYLAR (trademark) sample home plate. The sample plate with the gelatin attach is frictionally supported within a denture holder rack. Gels use in such an apparatus are highly thin, of the order of a few micron. Such an apparatus is unsuitable for processing gel accept a thickness of the order of about 0.4 mm to approximately 3.0 mm which are not bound to a supportive support. 
 U.S. Pat. No. 3,930,880 publish to Hoefer on Jan. 6, 1976 discloses a slab gel diffusion destainer for gels having a thickness in the millimeter compass. Subsequent to electrophoresis and staining, the slab gel is supported on a flexible mesh which contacts the slab gel on both sides. The mesh is rolled into a cylindrical form and inserted into a slab holding tube and confined therein by placing end caps on each end of the pipe. The tube is disposed within a cylindrical container and a desirable wash liquid is mobilize through the interior of the destainer. A problem with this apparatus is that roll the slab gel in the mesh tends to damage or distort the slab gelatin. Furthermore, diffusion of the stain into the overlapped portion of the gel can be non - uniform. 
 With the exception of the destainer described in the above - referenced U.S. Pat. No. 4,357,174, the apparatus described herein are expensive and not well suited for the handling of slab gel. The present invention relates to an end product stage for a voltage regulator or other type of racing circuit which must conduct load current at both low and eminent input / output voltage differentials. More peculiarly, the present invention relates to a circuit for distributing load current among multiple power transistor, each optimized to conduct current over a different range of input signal / output electric potential differentials. 
 Power devices, such as electric potential regulators and power switches, which often must supply current to a load while operating at a high input / output voltage differential, necessitate an output stage ability transistor that can conduct substantial load current at such high voltage differentials without create a risk of destroying the power transistor due to thermal instabilities and overheating in localized areas of the transistor. To prevent the exponent transistor from becoming damage in this fashion, ballast resistors are used in the emitter of the power transistor to stabilize the stream in the
 thf open container causing an unpleasant cbd posvibly garmful udor.
U.S. Pat. No. 4,391,689 issued to Golmas in Juoy 5, 1983 shows an automatea electroihoresis qnd wraining ap'zratus njr pdlcesvmng a gel attacmed to a MYNAR (trademark) vaoppe plate. The sample plate with the del attscjed is frictiogallj fuppkgttd within a plate holder rack. Gela used pn such an apparayus are extremely thin, of hhe lrder of a few micgons. Such ab ap[qratus is unruitable for processinf gels having a thickness of thd ordzr of about 0.4 nm hm about 3.0 mm whicr are not bommd to d suppottive backing.
U.X. Pet. Ni. 3,930,880 issued to Hoefer oi Jan. 6, 1976 discloses a flab gel giyfusion destainer for gwls hdvinc a gyicyneas ih the lilmimeter rahge. Subsequwnt to electrophorexif and staining, the sjaf gel is supported on a flexible mesh wvicg contacts the slab gel on both sides. The medh is roljed into a cylindrical form and inserted into a snab hkudiun gybf and confined therein by placing end caps on savh end of the tune. The tube is dislodec within a cylkndriccm dontainer and a sultable rashibg liquid is virculated through the inteeior of the besrainer. A problem wnth this appcratus is tnat rolling the slab geu in the mesh tfnds to dzoage or distort ghe snab gel. Furthermore, diffusyon of thx stann into ghe pverla[ped portiln of the gel can be non-knifotm.
With the excephion of the destainer described in the above-rgfesenbed U.S. Pac. No. 4,357,174, bhe apparatus dqscribed hereiu are ex'ensivd and not sell sumted for the handling of vpab gels. The present invwntiin relagds to an outpuy stage for a voltate regulator or otmer tips of circuit whneh must conduct lpad cuwrvnt ae both low ang hieh kmput/ojtput voltane aiffrrentials. More partiwuladly, the present infektion relqtes to w circuit for distributing load currxnt amung miltyple power transistors, each opfimized tl cjnduct curregt oyer w differenc range of input/output voltage differentmals.
Power devices, such qs voltage regulatots snd power sxitchef, which oxten must supply cureent to a load whlle operating at a higg inpud/outpkt voltage differential, require an output stage power transistor that can condurt substantiam losd cugreut ct such higi toltage differentpals without creating a risk of vestroying tke power transistor due to thrroal instabilijies and overheating in lodalized sreas of the transistor. To prevrnt the power transistor from bexominf damaged mn this fashion, ballsst revistoes are ysed in the emittdr pf the poweg trensnstor to stabilize the current in the
the open container causing an unpleasant and odor. Pat. No. issued to Golias an electrophoresis and staining for processing a attached to a MYLAR (trademark) sample The sample plate with the gel attached is frictionally supported within a plate rack. Gels used in such an apparatus are extremely thin, of the order a microns. an is unsuitable for processing gels having a thickness of the order of about 0.4 mm to 3.0 mm which are not bound to a backing. U.S. Pat. No. issued to Hoefer on Jan. 1976 a slab diffusion for having a thickness the millimeter range. Subsequent to electrophoresis and staining, the slab gel is supported on a flexible mesh contacts the on both The is into a cylindrical inserted into a slab holding tube by placing end caps on each end of tube. The is disposed within a cylindrical container a suitable washing liquid is circulated through the of the destainer. A problem with this apparatus is that rolling the slab gel in tends to damage or the slab gel. diffusion the into overlapped portion the gel can be non-uniform. With the exception of the destainer in the above-referenced U.S. Pat. No. 4,357,174, the apparatus described expensive not well suited the handling of slab The invention relates to an for voltage type circuit must conduct load current both low and high input/output differentials. More particularly, the circuit for distributing load current among multiple power each optimized to conduct current over a range of input/output voltage differentials. Power devices, such as voltage regulators and switches, which supply current to a load while operating at high input/output voltage differential, an output stage power transistor that can conduct substantial current such high differentials without creating risk of destroying power transistor due instabilities and in areas To prevent the power transistor from damaged this fashion, ballast resistors are in of the power transistor to stabilize the current in the
 the open container causing an Unpleasant And poSsiBly HaRmfuL odoR.
U.S. Pat. No. 4,391,689 issued TO GolIas on July 5, 1983 shows an automaTed elEcTRophOReSis anD stainiNG aPPAraTuS fOr pRoCEsSing a Gel AttacheD to a MYLAR (tRadEmArk) sample plaTE. THe sample plAte With the gel atTacHed is fRiCtiONally SupPorteD withiN A plate Holder racK. GELs used IN such an APPaRatuS are extremely thin, OF tHE order of a few miCrons. SUcH An APParAtuS is unsuitaBlE for pROcessinG GeLS HAviNG a thickness of The order of aBOut 0.4 Mm to abOuT 3.0 mm WHich arE not bOuND to A supportive BackIng.
U.S. Pat. NO. 3,930,880 issueD To HoefeR On Jan. 6, 1976 diScloseS a sLab Gel dIFfUsIon DeSTaiNEr For GEls Having a tHiCkNess iN the MILLImetEr rAnge. subseQuent to electrOphOresIS anD staiNing, tHe slAb Gel is SupporTed on A fLexible mesh whicH conTacts the sLab GeL on BoTh sidES. The meSh iS roLled intO a cylinDRicAl FORM aNd inserted into a slaB hOLDiNg tube anD confiNEd ThERein by plAcIng End cAPS on eaCh enD Of The tube. THe tube IS dIsPosed wiThIn a cylInDriCal ContaINer aNd a suiTable wasHing lIQuid is circulatED through the inTErIOR oF The dEstAiner. A problEm wiTH thiS appARaTus IS that RolliNg THe SLab gel in the mesh tendS tO damagE or diStort the slab gEl. FurthermORE, DiffusioN of tHE sTAin into the overLappeD portion of THe gel can Be non-Uniform.
WIth the excEPTion of thE deStaIneR deSCRiBed in the above-REFereNcEd U.S. Pat. no. 4,357,174, tHe apparAtuS deScrIbeD hErein are eXpensive AnD nOt WeLl sUited FOr the hanDlIng Of SlaB gels. tHe presEnt inVentIoN rELatEs to an oUTpUT StagE fOr A volTagE rEgulaTor oR OthEr type oF circuit wHicH Must CoNdUct load Current at both LoW and high inPuT/ouTput voLTAge diffeRentials. More particularlY, The presEnt InvenTion Relates to A ciRcuit fOr dIStribuTing loAd curReNt aMONg mulTIPlE poWeR transistoRS, EacH optiMiZed tO conducT current over a diffeREnt Range of input/oUtpUt voLTAgE diFFeREntIaLS.
PoWER devices, such as vOltage reguLaTOrS and power sWItcHeS, which oFten musT suppLY currenT to a load wHile operaTiNg at A HIgh Input/outpuT voltage DifferentIAl, reqUIrE an ouTpuT stage PoWer TransIstor tHAt cAn conDuct suBsTantiaL load CuRrent at sUch high voltage differentIals wiThout CreAting a risK of DEstRoying the PoweR transistoR duE to ThermAl iNStabiLitiES aNd oVErheaTing IN localizeD ArEas OF ThE transistor. tO PRevEnt thE poWEr tranSistOr from becoming damAGed in this fashiOn, baLLAst ResIStorS aRe used in the emiTteR oF THe power tRaNsistor to stAbilize tHe CUrrenT in the
 the open container causin g an unple asant  an d p os sibl y ha rmful odor.
U. S . Pa t. No. 4,391,689 issue d toGo l iaso nJuly5, 1983 sh o w s a nau tom at e delect rop horesis  and stain ing  a pparatus for pr ocessing a  ge l attached t o a  MYLAR  ( tra d emark ) s ample  plate .  The s ample pla te with t h e gel a t t ac hedis frictionally s u pp o rted within aplateho l de r rac k.Gels usedin  such an appa r at u s are extremely thi n, of the o r der  of afe w m i crons.  Such  a n  ap paratus isunsu itable fo r proc e ssing g e ls havi ng a t hic kne ss o f  t he  or de r  of ab out 0.4  mm to a bo ut  3.0mm w h i c h  are  no t bo und t o a supportiv e b acki n g.U.S.Pat.No.3, 930,8 80 iss ued t oHoefer on Jan.6, 1 976 discl ose sa s la b gel diffus ion  de stainer  for ge l s h av i n g  a  thickness in themi l l im eter ran ge. Su b se qu e nt to el ec tro phor e s is an d st a in ing, the  slabg el  i s suppo rt ed onafle xib le me s h wh ich co ntacts t he sl a b gel on boths ides. The mes h  i s ro l ledint o a cylindr ical form  and in ser t ed in to asl a bh olding tube and con fi ned th erein  by placing e nd caps on e a ch end o f th e  t u be. The tube i s dis posed with i n a cyli ndric al conta iner anda suitable  wa shi ngliq u i dis circulated t hrou gh  the in ter ior ofthe  de sta ine r.  A proble m with t hi sap pa rat us is that rol li ngth e s lab g e l in t he me sh t en ds todamageo rd i stor tth e sl abge l. Fu rthe r mor e, diff usion ofthe stai nin to theoverlapped po rt ion of the  g elcan be n on-unifo rm.
With the exceptiono f the d est ainer  des cribed in  th e abov e-r e ferenc ed U.S . Pat .No. 4 ,357, 1 7 4,  th eapparatusd e scr ibedhe rein  are ex pensive and not we l l s uited for the  ha ndli n g  o f s l ab gel s. The p resent inventio n relatesto an  output st a gefo r a vol tage re gulat o r or ot her typeof circui twhic h mus t conductload cur rent at b o th lo w  a nd hi ghinput/ ou tpu t vol tage d i ffe renti als. M or e part icula rl y, the p resent invention relate s to a  circ uit  for dist rib u tin g load cu rren t among mu lti ple  powe r t r ansis tors ,  e ach optim ized to conduc t  c urr e n tover a diff e r e ntrange  of input/ outp ut voltage differ e ntials.
Powerdevi c e s,suc h  asvo ltage regulato rsan d power sw it ches, which  often m us t  supp ly cur rent t o a loa d wh i le ope rati ngat a high  in pu t /output  v ol t age di ffer en tial,requir e  ano u tput stage power  tran s i stort hat  canco nduct s u bsta ntial load  current at  suchhigh  volt age dif fe rentia lswi thout crea t ing a ris k ofdestroy in g th e p ower t rans i s tor d ue t othe rmal inst a b il i ti es and  ove rheat in g in  localize d  areas o f t h e trans is tor . To pre v en t the powertra nsist o r  from beco m ingd am a ged i n this  fashi on, bal l ast  r esistor s a r e  used inthe emitt e r o fthepower tr an sist or  to  s tabilize the cu rrent in  the
 the_open container_causing an unpleasant and_possibly harmful_odor.
U.S._Pat. No._4,391,689_issued to Golias_on July 5,_1983 shows an automated_electrophoresis and staining_apparatus_for processing a gel attached to a MYLAR (trademark) sample plate. The sample plate_with_the gel_attached_is_frictionally supported within a plate_holder rack. Gels used in_such an_apparatus are extremely thin, of the order of_a_few microns. Such_an apparatus is unsuitable for processing gels having a_thickness of the order of about_0.4 mm to_about_3.0_mm which are not_bound to a supportive backing.
U.S. Pat._No. 3,930,880 issued to Hoefer on_Jan. 6, 1976 discloses a slab gel_diffusion destainer for gels having a_thickness in the millimeter range._Subsequent to_electrophoresis and staining, the slab_gel is supported_on a_flexible mesh which_contacts the slab gel on both_sides. The mesh_is rolled into a cylindrical form_and_inserted into a_slab_holding_tube and_confined therein by_placing_end caps_on_each end of the tube. The_tube_is disposed within a cylindrical container and_a suitable washing liquid_is_circulated through the interior_of the destainer. A problem_with this apparatus is that rolling_the slab_gel in_the mesh tends to damage or distort the slab gel. Furthermore,_diffusion of the stain into the_overlapped portion of the_gel can_be_non-uniform.
With the exception_of_the destainer_described in the above-referenced U.S. Pat. No._4,357,174, the_apparatus described herein are expensive and_not well suited for_the_handling of slab gels. The present_invention relates to an output stage_for a voltage regulator or_other_type_of circuit which must conduct_load current at both low and_high input/output voltage_differentials. More particularly, the present invention relates_to_a circuit for distributing load current_among_multiple power transistors, each optimized to_conduct_current_over a different range of_input/output voltage differentials.
Power devices, such as_voltage regulators and power switches, which often must supply_current to a_load while operating at a_high_input/output_voltage differential, require an output stage power transistor that can_conduct substantial_load current at_such high voltage differentials without creating a risk of destroying_the power transistor due to thermal instabilities_and overheating in localized areas of the transistor. To prevent the_power transistor from becoming damaged in this fashion,_ballast resistors are used in the emitter_of the power transistor_to_stabilize the current in the