DocumentationDatasheet
Design Note
Reliability Data
LT Journal
cad_symbol
Features
- 2.7V to 5.5V Input Voltage Range
- No Inductors
- Li-Ion (3.6V) to 1.5V with 81% Efficiency
- Low Noise Constant Frequency Operation
- Output Voltages: 1.5V ±4%, 1.2V ±4%
- Output Current: 250mA
- Shutdown Disconnects Load from VIN
- Low Operating Current: IQ = 35µA
- Low Shutdown Current: ISD <1µA
- Oscillator Frequency = 1.5MHz
- Soft-Start Limits Inrush Current at Turn-On
- Short-Circuit and Overtemperature Protected
- Low Profile (1mm) ThinSOT Package
Typical Application
Description
The LTC3250-1.5/LTC3250-1.2 are charge pump step-down DC/DC converters that produce a 1.5V or 1.2V regulated output from a 2.7V to 5.5V input. The parts use switched capacitor fractional conversion to achieve typical efficiency two times higher than that of a linear regulator. No inductors are required.
A unique constant frequency architecture provides a low noise regulated output as well as lower input noise than conventional charge pump regulators.* High frequency operation (fOSC = 1.5MHz) simplifies filtering to further reduce conducted noise. The part also uses Burst Mode® operation to improve efficiency at light loads.
Low operating current (35µA with no load, <1µA in shutdown) and low external parts count (three small ceramic capacitors) make the LTC3250-1.5/LTC3250-1.2 ideally suited for space constrained battery powered applications. The parts are short-circuit and over-temperature protected, and are available in a low profile (1mm) 6-pin ThinSOT package.
*U.S. Patent #6, 411, 531
SOT-23
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) |
Price (1k)* |
|---|---|---|---|---|---|
| LTC3250ES6-1.2#PBF | SOT | 6 | E | $2.12 | |
| LTC3250ES6-1.2#TRMPBF | SOT | 6 | E | $2.12 | $1.43 |
| LTC3250ES6-1.2#TRPBF | SOT | 6 | E | $2.12 | $1.41 |
| LTC3250ES6-1.5#PBF | SOT | 6 | E | $2.12 | |
| LTC3250ES6-1.5#TRMPBF | SOT | 6 | E | $2.12 | $1.43 |
| LTC3250ES6-1.5#TRPBF | SOT | 6 | E | $2.12 | $1.41 |
| LTC3250ES6-1.5 | SOT | 6 | E | $4.24 | |
| LTC3250ES6-1.5#TR | SOT | 6 | E | $4.24 | $2.82 |
| LTC3250ES6-1.2 | SOT | 6 | E | $4.24 | |
| LTC3250ES6-1.2#TR | SOT | 6 | E | $4.24 | $2.82 |
| LTC3250ES6-1.2#TRM | SOT | 6 | E | $4.24 | $2.86 |
| LTC3250ES6-1.5#TRM | SOT | 6 | E | $4.24 | $2.86 |
Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC488A | LTC3250ES6-1.5 Demo Board | Low Noise Regulated Step-Down Charge Pump, 3.1V ≤ VIN ≤ 5.5V, Vout = 1.5V @ 250mA | $75.00 |