|
|
|
MAX1920, MAX1921
Low-Voltage, 400mA Step-Down DC-DC Converters in SOT23
|
Status
Active: In Production.
Description
The MAX1920/MAX1921 step-down converters deliver over 400mA to outputs as low as 1.25V. These converters use a unique proprietary current-limited control scheme that achieves over 90% efficiency. These devices maintain extremely low quiescent supply current (50µA), and their high 1.2MHz (max) operating frequency permits small, low-cost external components. This combination makes the MAX1920/MAX1921 excellent high-efficiency alternatives to linear regulators in space-constrained applications.
Internal synchronous rectification greatly improves efficiency and eliminates the external Schottky diode required in conventional step-down converters. Both devices also include internal digital soft-start to limit input current upon startup and reduce input capacitor requirements.
The MAX1920 provides an adjustable output voltage (1.25V to 4V). The MAX1921 provides factory-preset output voltages (see the Selector Guide). Both are available in space-saving 6-pin SOT23 packages. The
MAX1920 is also available in a 6-pin TDFN package.
|
|
Data Sheet
|
An evaluation kit is available: MAX1921EVKIT
Key Features
- 400mA Guaranteed Output Current
- Internal Synchronous Rectifier for >90% Efficiency
- Tiny 6-Pin SOT23 Package
- Up to 1.2MHz Switching Frequency for Small External Components
- 50µA Quiescent Supply Current
- 0.1µA Logic-Controlled Shutdown
- 2V to 5.5V Input Range
- Fixed 1.5V, 1.8V, 2.5V, 3V, and 3.3V Output Voltages (MAX1921)
- Adjustable Output Voltage (MAX1920)
- ±1.5% Initial Accuracy
- Soft-Start Limits Startup Current
|
|
Applications/Uses
- Battery-Powered Applications
- CDMA Power Amplifier Supply
- Next-Generation Wireless handsets
- PDAs, Palmtops, and Handy Terminals
|
|
|
|
Key Specifications:
| Step-Down Switching Regulators |
| Part Number |
VIN
(V) |
VIN
(V) |
VOUT
(V) |
VOUT
(V) |
Preset VOUT
(V) |
Max. IOUT
(A) |
Output Adjust. Method |
DC-DC Outputs |
Oper. Freq.
(kHz) |
Package/Pins |
Smallest Available Pckg.
(mm2) |
Budgetary Price |
| min |
max |
min |
max |
≤ |
max w/pins |
See Notes |
| MAX1920 |
2 |
5.5 |
1.25 |
4 |
- |
0.4 |
Resistor |
1 |
1200 |
|
9 |
$1.35 @1k |
| MAX1921 |
1.5 |
3.3 |
|
|
|
$1.35 @1k |
|
See All Step-Down Switching Regulators (288)
|
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific prices and delivery, please see the price and availability page or contact an authorized distributor.
|
|
Diagram
 Typical Operating Circuit
More Information
Didn't Find What You Need?
Information Index
Document Ref.: 19-2296
Rev 3;
2005-09-20
This page last modified: 2007-07-05
|
|
|
Download
E-Mail