Features and Benefits
- Uses Off-the-Shelf Inductors
- Only 33µH Inductor Required
- Low Cost
- 3-Lead TO-92, SO8, or 8-Pin DIP
- Adjustable or Fixed 5V or 12V Output
- 120kHz Oscillator
- Only Three External Components Required
- 320µA IQ
- 1.6V Minimum Start-Up Voltage
- Logic Controlled Shutdown
The LT1109 is a simple step-up DC/DC converter. Available in 8-pin SO, 3-lead TO-92 (fixed output only) or miniDIP packages, the devices require only three external components to construct a complete DC/DC converter. Current drain is just 320µA at no load, making the device ideal for cost-sensitive applications where standby current must be kept to a minimum.
The LT1109-5 can deliver 5V at 100mA from a 3V input and the LT1109-12 can deliver 12V at 60mA from a 5V input. The 8-pin versions also feature a logic controlled SHUTDOWN pin that turns off the oscillator when taken low. The gated-oscillator design requires no frequency compensation components. The high frequency 120kHz oscillator permits the use of small surface mount inductors and capacitors. For a 5V to 12V at 120mA converter, see the LT1109A. For a 5V to 12V at 200mA converter with 20µA shutdown current, see the LT1301.
- Flash Memory VPP Generators
- 3V to 5V Converters
- 5V to 12V Converters
- Disk Drives
- PC Plug-In Cards
- Battery-Powered Equipment
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation & Resources
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Buy Now Pricing
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