lm2597hvn-5.0 National Semiconductor Corporation, lm2597hvn-5.0 Datasheet - Page 31

• Manufacturer Part Number: lm2597hvn-5.0
• Description: Simple Switcher Power Converter 150 Khz 0.5a Step-down Voltage Regulator, With Features
• Manufacturer: National Semiconductor Corporation

Application Information
(Continued)
eral hundred mA on the regulated positive output for the
charge pump to work correctly. Also, resistor R1 is required
to limit the charging current of C1 to some value less than
the LM2597 current limit (typically 800 mA).
This method of generating a negative output voltage without
an additional inductor can be used with other members of
the Simple Switcher Family, using either the buck or boost
topology.
DS012440-51
FIGURE 34. Charge Pump for Generating a
Low Current, Negative Output Voltage
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