MAX1921EUT33+T by Analog Devices

Low-Voltage, 400mA Step-Down DC-DC Converters in SOT23

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.

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Prices starting from US$1.93

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400mA Guaranteed Output Current
Internal Synchronous Rectifier for >90% Efficiency
Tiny 6-Pin SOT23 Package
Available in 6-Pin TDFN Package (MAX1920)
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


VIN (V) (min) 2
VIN (V) (max) 5.5
VOUT1 (V) (min) 1.5
VOUT1 (V) (max) 3.3
IOUT1 (A) (max) 0.4
Switch Type Internal
Preset VOUT (V) 3
Output Adjust. Method PresetResistor
Synchronous Switching? Yes
# DC-DC Outputs 1
Switching Frequency (kHz) 1200
Package/Pins SOT23/6
BudgetaryPrice (See Notes) 1.51

MAX1921EUT33+T Semiconductors - ICs by Analog Devices


Status: Unknown
Series: -
RoHS: Unknown
Download Datasheet Visit Manufacturer Site View Pricing & Stock


Topology Synchronous Buck (Step Down)
Input Voltage Min 2.5V
Input Voltage Max 5.5V
DC / DC Converter IC Case SOT-23
No. of Pins 6Pins
Output Current 400mA
Output Voltage Nom. 3.3V
Switching Frequency 1.2MHz
Operating Temperature Max 85°C
Product Range -
Automotive Qualification Standard -
RoHS Phthalates Compliant To Be Advised
MSL MSL 1 - Unlimited
SVHC No SVHC (15-Jan-2018)

Alternative Descriptions

Low-Voltage, 400mA Step-Down D | Analog Devices
DC/DC CONV, SYNC BUCK, 1.2MHZ, SOT-23-6 | element14
Dc/Dc Conv, Sync Buck, 1.2Mhz, Sot-23-6 | Newark Electronics

Frequently Asked Questions

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Is the MAX1921EUT33+T RoHS compliant?

This part has not been flagged as RoHS Compliant.

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