 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
SP6120BEY Datasheet(PDF) 10 Page - Sipex Corporation |
|
||||||||||||||||||||||||||||||
SP6120BEY Datasheet(HTML) 10 Page - Sipex Corporation |
|
|
10 / 22 page  10 Date: 5/25/04 SP6120B Low Voltage, AnyFETTM, Synchronous, Buck Controller © Copyright 2004 Sipex Corporation TIME 3% Low Enable Voltage V(VCC) 0V SWN Voltage V(VCC) 0V FAULT Reset Voltage V(VCC) 0V Inductor Current ILOAD 0V Error Amplifier Reference Voltage 0V 1.25V VOUT = V(Eamp REF)* (1+RF/RI) SS Voltage 0V 0.25V 0.7V 2.0V 2.4V dVSS/dt = 50µA/CSS V(ISP) - V(ISN) 0V 250mV V(VCC) 0V 0V 2.0V SS Voltage FAULT Voltage 2.4V 43mV As the figure shows, the SS voltage controls a variety of signals. First, provided all the external fault conditions are removed, the fault latch is reset and the SS cap begins to charge. When the SS voltage reaches around 0.3V, the error amp refer- ence begins to track the SS voltage while maintain- ing the 0.3V differential. As the SS voltage reaches 0.7V, the driver begins to switch the high side and low side MOSFETs with narrow pulses in an effort to keep the converter output regulated. As the error amp reference ramps upward, the driver pulses widen until a steady state value is reached. The “bump” in the inductor current transfer curve is indicative of excess charge current incurred due to the finite propagation delay of the controller. When the SS voltage reaches 2.0V, the second- ary loop including the 3% window comparator is enabled. Lastly, the SS voltage is clamped at 2.4V, ending the soft start charge cycle. Hiccup Mode When the converter enters a fault mode, the driver holds the high side and low side MOSFETs off for a finite period of time. Provided the part is enabled, this time is set by the discharge of the SS capacitor. The discharge time is roughly 10 times the charge interval thereby giving the power supply plenty of time to cool during an over current fault. The driver off-time is pre- dominantly determined by the discharge time. Restart will occur just like a normal soft start cycle. However, if a fault occurs during the soft start charge cycle, the FAULT latch is immediately set, turning off the high side and low side MOSFETs. The MOSFETs remain off during the remainder of the charge cycle and subse- quent discharge cycle of the SS capacitor. Again, provided there are no external fault conditions, the FAULT latch will be reset when the SS voltage reaches 250 mV. Over Current Protection The SP6120B over current protection scheme is designed to take advantage of three popular detection schemes: Sense Resistor, Trace Resis- tor or Inductor Sense. Because the detection threshold is only 43mV, both trace resistor and inductor sense become attractive protection schemes. The inductor sense scheme adds no additional dc loss to the converter and is an excellent alternative to Rdson based schemes; |
Similar Part No. - SP6120BEY |
|
Similar Description - SP6120BEY |
|
|
|
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 |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
