IW1689 Datasheet, PDF (1/17 Pages) Dialog Semiconductor – Low-Power Off-line Digital PWM Controller

iW1689
Low-Power Off-line Digital PWM Controller
1.0 Features
2.0 Description
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Primary-side feedback eliminates opto-isolators and
simplifies design
Multi-mode operation for highest overall efficiency
Very tight output voltage regulation
No external compensation components required
Complies with CEC/EPA/IEC no load power consumption
and average efficiency regulations
Built-in secondary constant-current control with primary-
side feedback
Low start-up current (8 µA typical)
Built-in soft start
Built-in short circuit protection
AC line under/overvoltage and output overvoltage
protection
Fixed switching frequency
Available in a space-saving SOT-23 package
The iW1689 is a high performance AC/DC power supply
controller which uses digital control technology to build
s _{sensorless peak current mode PWM flyback power}
n supplies. The device provides high efficiency along with a
number of key built-in protection features while minimizing
ig ^{the external component count and bill of material cost. The}
iW1689 removes the need for secondary feedback circuitry
s _{while achieving excellent line and load regulation. It also}
eliminates the need for loop compensation components while
e _{maintaining stability over all operating conditions. Pulse-by-}
D ^{pulse waveform analysis allows for a loop response that is}
much faster than traditional solutions, resulting in improved
dynamic load response. The built-in power limit function
enables optimized transformer design in universal off-line
w _{applications and allows for a wide input voltage range.}
e _{The ultra-low start-up power and operating current at light}
N load ensure that the iW1689 is ideal for applications targeting
the newest regulatory standards for average efficiency and
r _{standby power.}
Fo ^{3.0 Applications}
• Low power AC/DC adapter/chargers for cell phones,
PDAs, digital still cameras
d_{• Standby supplies for televisions, DVDs, set-top boxes}
e _{and other consumer electronics}
end _L
N
m₊
+
+
V_OUT
RTN
ecom₊
4 V_CC
OUTPUT 3
R _{GND 2}
t _{5 VIN}
V_SENSE 1
o _U1
N ^iW1689
Rev 2.0
Figure 2.0.1 iW1689 Typical Application Circuit
iW1689
November 7, 2012
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