ADP1821 Step-Down DC-to-DC Controller
The ADP1821 is a versatile and inexpensive, synchronous, pulse-width-modulated (PWM), voltage-mode, step-down controller. It drives an all N-channel power stage to regulate an output voltage as low as 0.6 V. The ADP1821 can be configured to provide output voltages from 0.6 V to 85% of the input voltage and is sized to handle large MOSFETs for point-of-load regulators.
The ADP1821 is well suited for a wide range of high power applications, such as DSP and processor core power in telecommunications, medical imaging, high performance servers, and industrial applications. It operates from a 3.7 V to 5.5 V supply with a power input voltage ranging from 1.0 V to 24 V.
The ADP1821 operates at a pin-selectable, fixed switching frequency of either 300 kHz or 600 kHz, minimizing external component size and cost. For noise sensitive applications, it can be synchronized to an external clock to achieve switching frequencies between 300 kHz and 1.2 MHz. The ADP1821 includes soft start protection to limit the inrush current from the input supply during startup, reverse current protection during soft start for precharged outputs, as well as a unique adjustable lossless current-limit scheme utilizing external MOSFET sensing.
The ADP1821 operates over the –40°C to +125°C junction temperature range and is available in a 16-lead QSOP.
Applications
- Telecommunications and networking systems
- Set-top boxes
- Printers
- Servers
- Medical imaging systems
- Microprocessor and DSP core power supplies
- Mobile communication base stations
Features and Benefits- Wide power-input voltage range: 1 V to 24 V
- Chip supply voltage range: 3.7 V to 5.5 V
- Wide output voltage range: 0.6 V to 85% of input voltage
- 1% accuracy, 0.6 V reference voltage
- All N-channel MOSFET design for low cost
- Fixed-frequency operation 300 kHz, 600 kHz, or synchronized operation up to 1.2 MHz
- No current sense resistor required
- Power-good output
- Programmable soft start with reverse current protection
- Soft start, thermal overload, current-limit protection
- Undervoltage lockout
- 10 μA shutdown supply current
| Design Tools |
Data Sheets
Application Notes
Product Highlight
Order Information
| Part Number | Package | Packing Qty | Temp Range | Price 100-499 | Price 1000+ | RoHS |
|---|
| ADP1821ARQZ-R7 Production | 16 ld QSOP | REEL 1000 | -40 to 85C | 0 | 1.41 | Y |
Evaluation Boards
| Part Number | Description | Price | RoHS |
|---|
| ADP1821-EVALZ | Evaluation Board | 60.72 | Y |
Reference Materials
