A4402: Constant On-Time Buck Converter With Integrated Linear Regulator

Description

The A4402 is a dual-output regulator, combining in a single package a constant on-time buck regulator and a linear regulator (LDO)—each with adjustable output voltages. It is ideal for applications that require two regulated voltages, such as in microcontroller- or DSP-based applications requiring core and I/O voltage rails.

The buck regulator output supplies the adjustable linear regulator to reduce power dissipation and increase overall efficiency. The switching regulator is capable of operating above 2 MHz, allowing the use of small low value inductors and capacitors while avoiding sensitive EMI frequency bands such as AM radio in automotive applications.

Protection features include undervoltage lockout and thermal shutdown. In case of a shorted load, each regulator features overcurrent protection.

The device has an integrated power-on reset with adjustable delay to monitor LDO output voltage and provide a signal that can be used to reset a DSP or microcontroller. It also includes a watchdog circuit.

The A4402 is provided in a 16-pin TSSOP, with exposed pad for enhanced thermal dissipation. It is lead (Pb) free, with 100% matte tin leadframe plating.

Top Features

  • 2 MHz switching frequency
  • Adjustable soft start timer
  • Watchdog input
  • Power-on reset output
  • Adjustable buck and linear regulators
  • Enable input
  • 6 to 50 V supply voltage range
  • Overcurrent protection
  • Undervoltage lockout (UVLO)
  • Thermal shutdown protection

Typical Applications

 

AUTOMOTIVE

COMMERCIAL

 

Part Number Specifications and Availability

Part Number Package Type Temperature RoHS
Compliant
Part Composition /
RoHS Data
Comments Samples Check Stock
A4402ELPTR-T 16-lead TSSOP -40°C to 85°C Yes View Data Contact your
local sales rep
Check
Distributor Stock
APEK4402KLP-01-T DEMO BOARD -40°C to 125°C No -- Contact your
local sales rep
Check
Distributor Stock
A4402KLPTR-T 16-lead TSSOP -40°C to 150°C Yes View Data Contact your
local sales rep
Check
Distributor Stock

Allegro’s products are not to be used in any devices or systems, including but not limited to life support devices or systems, in which a failure of Allegro’s product can reasonably be expected to cause bodily harm.

Allegro 16-Pin LP package

Packaging

The A4402 is provided in a 16-pin TSSOP, with exposed pad for enhanced thermal dissipation. It is lead (Pb) free, with 100% matte tin leadframe plating.

LP Package Documentation