XRP7740ILB-0X18-F Exar Corporation, XRP7740ILB-0X18-F Datasheet - Page 26

• Manufacturer Part Number: XRP7740ILB-0X18-F
• Description: IC CTRLR PWM/LDO STP-DWN 40TQFN
• Manufacturer: Exar Corporation
• Series: -r

Specifications of XRP7740ILB-0X18-F

• Topology: Step-Down (Buck) Synchronous (4), Linear (LDO) (1)
• Function: Any Function
• Number Of Outputs: 5
• Frequency - Switching: 1.5MHz
• Voltage/current - Output 1: Controller
• Voltage/current - Output 2: Controller
• Voltage/current - Output 3: Controller
• W/led Driver: No
• W/supervisor: No
• W/sequencer: Yes
• Voltage - Supply: 6.5 V ~ 20 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: *
• Package / Case: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 1016-1697

Total input voltage ripple is the sum of the above:
Selecting MOSFETs with lower Rdson reduces conduction losses at the expense of increased
switching losses. A simplified expression for conduction losses is given by:
MOSFET’s junction temperature can be estimated from:
This assumes that the switching loss is the same as the conduction loss.
thermal resistance from junction to ambient.
L
Refer to application note ANP-32 “Practical Layout Guidelines for Power
© 2011 Exar Corporation
Power MOSFETs Selection
AYOUT
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UIDELINES
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a
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