XR21B1421IL28-F Overview
There is a copy of it in the QFN package. It is easy to carry thanks to its Cut Tape-shaped packaging. The terminations in it can be broken down into 28's. Providing a voltage of 3.3V leads to high efficiency. In order for the device to function, 28 pins must be used. BUS CONTROLLER, UNIVERSAL SERIAL BUS uPs, uCs, and peripheral ICs are present in this gadget. It is set to 13mA for the supply current to the gadget. It is made possible by the maximum operating temperature of 85°C°C, enabling stable operation. To ensure reliability, it requires a minimum temperature of -40°C degrees Celsius. Despite a supply voltage of 5.25VV, it can withstand it. There is no need to worry about the source voltage of 4.4V since the device can work with a low voltage.
XR21B1421IL28-F Features

XR21B1421IL28-F Applications
There are a lot of Exar Corporation
XR21B1421IL28-F Controllers Interface ICs applications.

Dimming Control Devices
Commercial LED Lighting
Smart LED Lighting
Portable Appliances
Battery-Operated Devices
Cellular Data Devices
Factory Automation and Process Controls
IrDA transmission control
Remote transmission formatter
Docking

Package / Case	QFN
Surface Mount	YES
Number of Pins	28
Packaging	Cut Tape
Number of Terminations	28
Max Operating Temperature	85°C
Min Operating Temperature	-40°C
HTS Code	8542.31.00.01
Terminal Position	QUAD
Terminal Form	NO LEAD
Peak Reflow Temperature (Cel)	NOT SPECIFIED
Supply Voltage	3.3V
Time@Peak Reflow Temperature-Max (s)	NOT SPECIFIED
Temperature Grade	INDUSTRIAL
Interface	UART
Max Supply Voltage	5.25V
Min Supply Voltage	4.4V
Operating Supply Current	13mA
uPs/uCs/Peripheral ICs Type	BUS CONTROLLER, UNIVERSAL SERIAL BUS
Height	1mm
Length	5mm
Width	5mm
REACH SVHC	Unknown
RoHS Status	RoHS Compliant