NXP GreenChip SMPS
transient controller TEA1705
Optimized battery charging up to 12W
When used to monitor the output voltage of the secondary side in an SMPS application, this cost-
effective transient controller helps deliver exceptionally fast dynamic load response.
Key features
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Excellent transient performance with ultra-low no-load
power and smallest output capacitors
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Fast detection of a decreasing output voltage during load
steps
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Device available in small SOT-23 package
Applications
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Battery chargers for smartphones and media tablets up to
12 W
`
Standby supplies for TVs and desktop PCs
The NXP TEA1705 is a secondary side IC for use in Switched
Mode Power Supplies (SMPS) with high power density. It offers
excellent transient response of primary controlled systems,
with ultra-low no-load power and minimum-sized output
capacitors. The output voltage is continuously monitored
and when the output voltage is below the threshold level,
a transient interrupt signal is generated. This signal is
transmitted via the transformer to the primary side to wake
up the primary controller. This system reduces the volume of
the output capacitors and makes it possible to build compact
chargers.
The TEA1705 is ideally suited for use with the NXP TEA1720A,
a small, low-cost SMPS controller that operates directly
from the rectified universal mains output and can detect the
communication pulse from the TEA1705. The two devices
combine to create a system that delivers very tight transient
response (5 V ±5%) with small output capacitors and very low
no-load power up to 12 W.
The TEA1720A/TEA1705 combination delivers integrated HV
start-up, ultra-low no-load power (<10 mW), improved CC
mode accuracy of less than 10%, and external low-cost NPN
power transistor. The TEA1720A/TEA1705 combination is also
compliant to the USB 1.1 and 1.2 charging specifications. The
result is a low-power converter built at minimum cost and with
a minimum number of external components.
TEA1720A
Primarily designed for phone and media tablet chargers
operating up to 12 W, the GreenChip TEA1720A includes
an emitter switch for driving an external low-cost bipolar
power transistor. It has been optimized for flyback converter
NXP [ NXP Semiconductors ]
