                    ENGINEERING CHANGE NOTICE

ECN Number:_____________4___________________

Product:__Decision 1 switching power supply_

Part Number(s):______SWPS-UN________________

Current Board Revision Number:____C-5671B___

New Board Revision Number:________C-5671C___


Purposĺ  oć Change:___This_change_is_to_limit_the_amount_of____

_current_absorbed_by_the_zener_and_transistor_in_the_blocking__

_oscillator_circuit_during_power_on_sequences._________________


Modificationó (attacč additionaě sheetó ić needed)ş _____________    

Thió_changĺ_requireó_thĺ_removaě_oć_onĺ_jumpeň_anä_thĺ_addition__ Ť

_a_220_ohm,_1_watt_resistor_in_place_of_the_jumper.______________

_Thió_changĺ_ió_conditionaě_oî_whicč_transformeň_(T3©_ió_oî_the“__ 

_board®_Thĺ_transformeň_(aó_showî_iî_figurĺ_2©_shoulä_looë_like“__ 

_thĺ_transformeň_iî_figurĺ_4®__Ić_iô_lookó_likĺ_thĺ_onĺ_iî_figure“ 

_3¬_iô_musô_bĺ_replaceä_beforĺ_thió_moä_maů_bĺ_done!!____________

APPROVED:      Engineering:______________________Date__/__/__

               Production:_______________________Date__/__/__

               Quality Assurance_________________Date__/__/__

               Customer Service__________________Date__/__/__

               Purchasing________________________Date__/__/__

               Marketing_________________________Date__/__/__

EFFECTIVITY:   [X]  Immediate - notify current production

               [X]  Notify users and update stock

               [ ]  Phase in as stock is depleted

Submitted by:___Bob_Groppo_______________________on 10/05/83

Page_1_of_6_                                 Schematics?_YES___Š                        ENGINEERING CHANGE NOTICE

ECÎ Number:______4__________ß                      Dateş _10/04/83_

PRODUCTş  __SWPS-UN_____________ß                  Pageş  _2ß oć _6_




MODIFICATIONSş      a© Removĺ jumpeň aó showî iî figurĺ ± steđ A.

                    b© Instalě  22°  ohm¬  ± watô  (oň  ˛  watt© Ť
                       resistoň aó showî iî figurĺ ± steđ B.

                    c© Alsď  notĺ thaô thĺ zeneň diodĺ  (D6©  aó Ť
                       showî  iî figurĺ 1Â anä figurĺ ˛  musô  bĺ Ť
                       rateä aô 15° Ö ± watt®   Twď 7µ V¬  ± watô Ť
                       deviceó  ió  alsď acceptable®   Somĺ  verů Ť
                       earlů supplieó haä otheň valueó whicč wilě Ť
                       noô   funtioî  correctlů  anä  shoulä   bĺ Ť
                       replaced.
                    
                    d© Alsď notĺ thaô iî nď instancĺ shoulä  thĺ Ť
                       transformeň  aó showî iî figurĺ 3 bĺ  lefô Ť
                       iî thĺ circuit.

                    e© Marë boarä witč thĺ designatioî  PC-5671Ă Ť
                       iî placĺ oć thĺ PC-5671B wherĺ marked.






                Change power supply Bill of Materials:

ADD:

QTY.  DESCRIPTION                      REF. DES.       MORROW PART #

 1    RESISTOR, 220 OHM, 1 WATT, 5%      R52            NONE


                                  OR 


 1    RESISTOR, 220 OHM, 2 WATT, 5%      R52            030-C0505-221


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