Electronic Components Datasheet Search |
|
IR3508MPBF Datasheet(PDF) 9 Page - International Rectifier |
|
IR3508MPBF Datasheet(HTML) 9 Page - International Rectifier |
9 / 19 page IR3508 Page 9 of 19 October 27, 2008 PHASE IC CLOCK PULSE EAIN VDAC PWMRMP GATEH GATEL STEADY-STATE OPERATION DUTY CYCLE DECREASE DUE TO VIN INCREASE (FEED-FORWARD) DUTY CYCLE INCREASE DUE TO LOAD INCREASE STEADY-STATE OPERATION DUTY CYCLE DECREASE DUE TO LOAD DECREASE (BODY BRAKING) OR FAULT (VCCLUV, OCP, VID=11111X) Figure 3: PWM Operating Waveforms Body BrakingTM In a conventional synchronous buck converter, the minimum time required to reduce the current in the inductor in response to a load step decrease is; O MIN MAX SLEW V I I L T ) ( * The slew rate of the inductor current can be significantly increased by turning off the synchronous rectifier in response to a load step decrease. The switch node voltage is then forced to decrease until conduction of the synchronous rectifier’s body diode occurs. This increases the voltage across the inductor from Vout to Vout + VBODYDIODE. The minimum time required to reduce the current in the inductor in response to a load transient decrease is now; BODYDIODE O MIN MAX SLEW V V I I L T ) ( * Since the voltage drop in the body diode is often comparable to the output voltage, the inductor current slew rate can be increased significantly. This patented technique is referred to as “body braking” and is accomplished through the “body braking comparator” located in the phase IC. If the error amplifier’s output voltage drops below the output voltage of the share adjust amplifier in the phase IC, this comparator turns off the low side gate driver. Lossless Average Inductor Current Sensing Inductor current can be sensed by connecting a series resistor and a capacitor network in parallel with the inductor and measuring the voltage across the capacitor, as shown in Figure 4. The equation of the sensing network is, CS CS L L CS CS L C C sR sL R s i C sR s v s v 1 ) ( 1 1 ) ( ) ( |
Similar Part No. - IR3508MPBF |
|
Similar Description - IR3508MPBF |
|
|
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 |