Electronic Components Datasheet Search |
|
IR3537 Datasheet(PDF) 11 Page - International Rectifier |
|
IR3537 Datasheet(HTML) 11 Page - International Rectifier |
11 / 15 page www.irf.com | © 2014 International Rectifier January 9, 2015 | V1.2 11 IR3537 CHL8510 12V High Performance Gate Driver supply voltage plus the HVCC voltage less the diode forward voltage. When the PWM signal goes low, the MOSFET is turned off by pulling the MOSFET gate to the SWITCH voltage. LOW‐SIDE DRIVER The IR3537/CHL8510 low‐side driver is designed to drive an external N‐channel MOSFET referenced to ground at up to 1MHz. The low‐side driver is connected internally to the LVCC supply voltage. ADAPTIVE DEAD TIME ADJUSTMENT In a synchronous buck configuration, dead time between the turn off of one gate and turn on of the other is necessary to prevent simultaneous conduction of the external MOSFETS preventing a shoot‐through condition which would result in a short of the supply voltage to ground. A fixed dead time does not provide optimal performance across a variety of MOSFETs and board layouts. The IR3537/CHL8510 provides an ‘adaptive’ dead time adjustment. This feature minimizes dead time which maximizes efficiency. The ‘break before make’ adaptive design is achieved by monitoring gate and SWITCH voltages to determine OFF status of a MOSFET. It also provides zero‐voltage switching (ZVS) of the low‐side MOSFET with minimum current conduction through its body‐diode. When the PWM is switching between 1.8V and 0V, its falling edge transition from high to low will turn off the high‐side gate driver. The adaptive dead time circuit monitors the HI_GATE and the SWITCH node voltages during the high‐side MOSFET turn off. When the HI_GATE falls below 1.7V above the SWITCH node potential or the SWITCH node voltage drops below 0.8V, the high‐side MOSFET is determined to be turned off, and the LO_GATE turn‐on is initiated. This turns on the external low‐side MOSFET. The rising edge transition of the PWM signal from low to high voltage causes the low‐side gate driver to turn off. The adaptive circuit monitors the voltage at LO_GATE and when it falls below 1.7V, the low‐side MOSFET is turned off, and the high‐side MOSFET turn‐on is initiated. This turns on the external high‐side MOSFET. INDEPENDENT VARIABLE GATE VOLTAGE The IR3537/CHL8510 features independent variable gate voltages for both the high‐ and low‐side drivers. This enables implementation of the Variable Gate Drive (VGD) feature in VR circuits using the IR multiphase controllers to improve efficiency. The voltage applied to the HVCC and LVCC pins of IR3537/CHL8510 determines the gate voltage on the external MOSFETs. These pins may be powered from independent voltage sources or tied together to a common voltage source. Variation in the gate voltage allows efficiency to be optimized across the load current range by trading off conduction and switching losses. Increasing the voltage across a MOSFET gate, results in reduced Rdson which lowers the MOSFET conduction losses, but also raises the gate charge which increases the switching losses. The voltage on each HVCC and LVCC pin, and thus the gate drive voltage of the CHL8510, can be varied from 4.5V to 13.2V. The International Rectifier’s digital multiphase controllers provide a unique VAR_GATE output which varies inversely with the VR output current. The VAR_GATE output is designed to be used with an external circuit and provide the optimum voltage across the IR3537/CHL8510’s HVCC and LVCC pins for optimum system efficiency across the load range. |
Similar Part No. - IR3537 |
|
Similar Description - IR3537 |
|
|
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 |