CamSemi launches ‘fast start’ controllers for
8W and 10W smartphone chargers
Date: 08/21/2014
Categories: Battery Charging & Management, Embedded Systems, Power ICs, Power Management
CamSemi announced two of their latest ‘fast start’ Primary Side Sensing (PSS) controllers to extend the target
applications for the company’s latest generation C2170 family into higher powers. The new C2173 and C2174
controllers target low cost MoU-compliant, USB smartphone charger and other universal input applications
typically rated at 8 W and 10 W respectively.
These two latest CamSemi controllers are the industry’s first PSS controllers at this power level to offer
manufacturers the combination of three significant cost and performance benefits within the same device: more
efficient switching of bipolar transistors (BJT) to deliver the higher operating efficiencies required by US
Department of Energy level 6 efficiency regulations and tier two of Europe’s Code of Conduct version five
(effective 1 January 2016); five star (less than 30 mW) no-load power performance (NLP); and fast-start
charging without needing an active start-up switch. Both devices feature integrated output transient detection
(TD) to enable manufacturers to further reduce NLP while maintaining fast transient response.
In addition, the controllers offer programmable dynamic response allowing one part to be easily configured in
multiple designs by specifying one of four resistor values. This approach provides manufacturers with greater
design flexibility and easier inventory management compared with competitive solutions where transient
response speed, NLP and other parameters are defined at the IC level.
The C2173 and C2174 use the company’s patented BJT drive scheme, as well as a further improvement in IC
power consumption enabling BJTs to be more easily used at higher powers. C2174 is also the first PSS
controller to use CamSemi’s patented supplementary base drive scheme to further reduce IC power dissipation
and junction temperature and to enable the performance advantages of combined base and emitter switching
at higher powers. Both controllers offer class-leading load transient response with passive start-up speeds well
below 0.5 second, whereas competitive approaches require an additional active start-up switch to ensure fast
start of charging cycles.
“CamSemi’s new C2173 and C2174 controllers will significantly expand the range of smartphone charger
applications we can now address and further boost our strong sales and share in this market. We are also
continuing to develop this low cost, more energy-efficient approach into higher powers and as part of our
strategy to target additional fast-growing segments,” said David Baillie, CEO of CamSemi.
C2173 and C2174 offer the same performance benefits as existing C2170 controllers targeting lower power
applications including: an increased Reverse Bias Safe Operating Area (RBSOA) margin to accommodate a
wide range of low cost BJTs; ‘best in class’ voltage regulation of +/- 2% and current regulation of +/- 3%
offering more margin for thermal design; and full featured protection.
C2173 is packaged in SOT23-6, C2174 in SOP8 and samples of both controllers are available now. Shortform
datasheets can be downloaded from www.camsemi.com/datasheets with more detailed design information
available from CamSemi or one of the company’s distributors.
Updates on the latest efficiency, EMI and other standards
CamSemi