LM5117PMH/NOPB National Semiconductor, LM5117PMH/NOPB Datasheet - Page 28

• Manufacturer Part Number: LM5117PMH/NOPB
• Description: IC BUCK CONTROLLER 20-TSSOP
• Manufacturer: National Semiconductor
• Series: -r

Specifications of LM5117PMH/NOPB

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 530kHz
• Duty Cycle: 95%
• Voltage - Supply: 5.5 V ~ 65 V
• Buck: Yes
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 20-TSSOP (0.173", 4.40mm Width) Exposed Pad
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

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Example of Constant Current
Regulator
The LM5117 can be configured as a constant current regula-
tor by using the current monitor feature (CM) as the feedback
input. A voltage divider at the VCCDIS pin from VOUT to
AGND can be used to protect against output over-voltage.
FIGURE 20. Constant Current Regulator with Hiccup Mode Output OVP
28
When the VCCDIS pin voltage is greater than the VCCDIS
threshold, the controller disables the VCC regulator and the
VCC pin voltage decays. When the VCC pin voltage is less
than the VCC UV threshold, both HO and LO outputs stop
switching. Due to the time delay required for VCC to decay
below the VCC UV threshold, the over-voltage protection op-
erates in hiccup mode. See
Figure
20.
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