Electronic Components Datasheet Search |
|
EFS21-TL5 Datasheet(PDF) 8 Page - STMicroelectronics |
|
EFS21-TL5 Datasheet(HTML) 8 Page - STMicroelectronics |
8 / 14 page EFS 8/14 In order to reduce the number of components, an auxiliary power supply is integrated in the ASD ™. This active power supply works directly on the mains and requires only a low voltage capacitor 16V - 22 µF. The operating mode of this supply varies with the starter operating phase: 4/ AUXILIARY POWER SUPPLY: DRIVER ASD VCC G1 GND TUBE C SUPPLY 7.57 7.68 D1 R1 R2 R6 POWER SUPPLY SCHEMATIC Supply operation during preheat phase: During preheat phase, the driver manages alone the supply function (neither the driver nor D1 and R6 are involved). A part of the current flowing through the ASD ™ is used, at the beginning and at the end of each positive mains half cycle, to charge the output capacitor. Supply operation during standby phase: When the lamp is lit, the monitors its supply voltage (Vcc). At the beginning of each positive mains half cycle, when Vcc is lower than 7.57V, the driver closes the ASD ™ supply switch. The capacitor is charged to provide the standby current of the driver. During this phase the tube lamp is short circuited by the ASD ™. When the supply voltage reaches 7.68V, the driver opens the ASD™ supply switch. Since this current is also flowing in the ballast, the supply turn off provides across the lamp an additional voltage spike. After running few minutes the lamp becomes warm and this spike voltage naturally decreases. SUPPLY DURING PREHEAT PHASE Starter current Starter voltage at the ignition 5min after ignition SUPPLY DURING STANDBY PHASE (Without E.M.I. Capacitor nor R6 nor D1) To reduce dramatically this repetitive voltage spikes across the lamp, the R6 resistor with the diode D1 provide a part of the supply current. Thus, the ripple voltage of the supply voltage is reduced, as well as the level of the switched off current. On the other hand, this increases the safety margin of the RF noise (versus the IEC 55015 limits) |
Similar Part No. - EFS21-TL5 |
|
Similar Description - EFS21-TL5 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |