Product category:
Power Supply ICs and Controllers
News Release from: Texas Instruments (April 2001-March 2006) | Subject: UCC27221 and UCC27222
Edited by the Electronicstalk Editorial
Team on 16 January 2003
Efficiency boost for synchronous buck
drivers
Texas Instruments has two new synchronous buck drivers for high-efficiency nonisolated low-output-voltage DC/DC convertors.
Texas Instruments has two new synchronous buck drivers for high-efficiency nonisolated low-output-voltage DC/DC convertors Providing system power designers up to 4% more efficiency and up to 40% improved heat dissipation, each driver can be used with 12 or 5V input systems, or with 3.3V input systems with higher bias rail, to generate lower output voltages for central processing units (CPU), general computer, data communications, telecommunications and general merchant power supply applications
This article was originally published on Electronicstalk on 8 Nov 2004 at 8.00am (UK)
Related stories
Data buffer has dual multiplexer
Texas Instruments has introduced the industry's first 0- to 4-Gbps data buffer/signal conditioner with a dual multiplexer.
Reference design for wireless optical comms
A new technology from Texas Instruments dramatically cuts the cost and complexity of bringing the high-speed datarates of optical networking to end users.
"Typical gate drivers with adaptive delay techniques wait for one switch to be turned off before turning on the other to prevent crossconduction, which always results in an inherent dead-time where body diode conduction losses occur", said John Vigars, Product Line Manager for TI's power supply control products.
"With today's low output voltages and higher operating frequencies requirements, these body-diode losses become increasingly significant.
These new drivers quickly find the optimal overlap between both gate drive transitions to eliminate the body-diode conduction and adjust for temperature variations and load-dependent delays".
The UCC27221 and UCC27222 drivers, which produce +/-3A of output drive current for efficient power mosfet switching at the critical Miller plateau region, employ TI's Predictive Gate Drive control technology to reduce diode conduction and reverse recovery losses in the synchronous rectifier mosfets.
This proven technology employs a closed loop feedback system that detects body-diode conduction, and adjusts dead time delays in the next switching cycle to minimise the conduction time interval in synchronous rectifiers.
Both drivers incorporate TI's hybrid TrueDrive output stage with paralleled bipolar and complementary metal-oxide semiconductor (CMOS) transistors to allow efficient current delivery at low supply voltages.
The UCC27221 has an inverted pulse-width modulation (PWM) input while the UCC27222 has a noninverting PWM input.
Latch up and electrostatic discharge protection circuitries are also included.
The UCC27221 and UCC27222 are available in volume from TI and its authorised distributors in a thermally enhanced low profile HTSSOP-14 PowerPAD (PWP) package.
Suggested resale pricing in quantities of 1000 units is $1.25.
Evaluation modules are available now.
• Texas Instruments (April 2001-March 2006): contact details and other news
• Email this article to a colleague
• Register for the free Electronicstalk email newsletter
• Electronicstalk Home Page
Search the Pro-Talk network of sites
