LM2598S-ADJ National Semiconductor, LM2598S-ADJ Datasheet - Page 29

• Manufacturer Part Number: LM2598S-ADJ
• Description: SIMPLE SWITCHER Power Converter 150 kHz 1A Step-Down Voltage Regulator/ with Features
• Manufacturer: National Semiconductor

Application Information
(Continued)
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
LM2598 current limit (typically 1.5A).
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.
DS012593-48
FIGURE 31. Charge Pump for Generating a
Low Current, Negative Output Voltage
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