The controller utilizes a constant on-time control scheme which eliminates the need for external compensation components, allowing the power supply designer to minimize necessary board space and reduce costs.
This design incorporates a 22µF ceramic output capacitor. Due of the lack of ESR on ceramic capacitors, a separate 50mOhm resistor is used for creating sufficient ripple at the output.
A 3.3 uH inductor value is used along with a 10 nF feedforward capacitor to help ensure stability. The 2000 ns LM1770 timing option accommodates 272 kHz operation.
| Manufacturer | Texas Instruments |
|---|---|
| Category | AC/DC and DC/DC Conversion |
| Sub-Category | DC/DC SMPS - Single Output |
| Eval Board |
ABC
|
| Topology |
Step Down
|
| Outputs and Type |
1 Non-Isolated
|
| Output Voltage: Factory Set |
1.8 V
|
| Current Out |
2 A
|
| Voltage In |
3.3 V
|
| Efficiency @ Conditions |
>86%, 3.3V in, 1.8 V @ 0.3 ~ 2 A
|
| Voltage Out Range | |
| Features |
Short Circuit Protection
Soft Start |
| Switching Frequency |
272 kHz
|
| Standby Current [Typical] | |
| Quiescent Current [Typical] |
400 µA
|
| Component Count + Extras |
10 + 0
|
| Internal Switch |
No
|
| Design Author |
Texas Instruments
|
| Application / Target Market |
Computers
DVD Players Point of Load (PoL) Portable Devices Set-Top Boxes Telecom USB Powered Devices White Goods |
| Main I.C. Base Part |
LM1770U
|
| Standby Current [Maximum] | |
| Quiescent Current [Maximum] |
600 µA
|
| Date Created By Author | |
| Date Added To Library | 2011-03 |
