Datasheet
LNK302/304-306
LinkSwitch-TN Family
www.powerint.com June 2013
Lowest Component Count, Energy-Efcient
Off-Line Switcher IC
™
This Product is Covered by Patents and/or Pending Patent Applications.
Output Current Table
1
Product
4
230 VAC ±15% 85-265 VAC
MDCM
2
CCM
3
MDCM
2
CCM
3
LNK302P/G/D 63 mA 80 mA 63 mA 80 mA
LNK304P/G/D 120 mA 170 mA 120 mA 170 mA
LNK305P/G/D 175 mA 280 mA 175 mA 280 mA
LNK306P/G/D 225 mA 360 mA 225 mA 360 mA
Table 1. Output Current Table.
Notes:
1. Typical output current in a non-isolated buck converter. Output power capability
depends on respective output voltage. See Key Applications Considerations
Section for complete description of assumptions, including fully discontinuous
conduction mode (DCM) operation.
2. Mostly discontinuous conduction mode.
3. Continuous conduction mode.
4. Packages: P: DIP-8B, G: SMD-8B, D: SO-8C.
Product Highlights
Cost Effective Linear/Cap Dropper Replacement
• Lowest cost and component count buck converter solution
• Fully integrated auto-restart for short-circuit and open loop
fault protection – saves external component costs
• LNK302 uses a simplified controller without auto-restart for
very low system cost
• 66 kHz operation with accurate current limit – allows low cost
off-the-shelf 1 mH inductor for up to 120 mA output current
• Tight tolerances and negligible temperature variation
• High breakdown voltage of 700 V provides excellent input
surge withstand
• Frequency jittering dramatically reduces EMI (~10 dB)
• Minimizes EMI filter cost
• High thermal shutdown temperature (+135 °C minimum)
Much Higher Performance Over Discrete Buck and
Passive Solutions
• Supports buck, buck-boost and flyback topologies
• System level thermal overload, output short-circuit and open
control loop protection
• Excellent line and load regulation even with typical configuration
• High bandwidth provides fast turn-on with no overshoot
• Current limit operation rejects line ripple
• Universal input voltage range (85 VAC to 265 VAC)
• Built-in current limit and hysteretic thermal protection
• Higher efficiency than passive solutions
• Higher power factor than capacitor-fed solutions
• Entirely manufacturable in SMD
EcoSmart
™
– Extremely Energy Efficient
• Consumes typically only 50/80 mW in self-powered buck
topology at 115/230 VAC input with no-load (opto feedback)
• Consumes typically only 7/12 mW in flyback topology with
external bias at 115/230 VAC input with no-load
• Meets California Energy Commission (CEC), Energy Star, and
EU requirements
Applications
• Appliances and timers
• LED drivers and industrial controls
Description
LinkSwitch-TN is specifically designed to replace all linear and
capacitor-fed (cap dropper) non-isolated power supplies in the
under 360 mA output current range at equal system cost while
offering much higher performance and energy efficiency.
LinkSwitch-TN devices integrate a 700 V power MOSFET,
oscillator, simple On/Off control scheme, a high-voltage switched
current source, frequency jittering, cycle-by-cycle current limit
Figure 1. Typical Buck Converter Application (See Application Examples Section
for Other Circuit Configurations).
and thermal shutdown circuitry onto a monolithic IC. The start-up
and operating power are derived directly from the voltage on the
DRAIN pin, eliminating the need for a bias supply and associated
circuitry in buck or flyback converters. The fully integrated
auto-restart circuit in the LNK304-306 safely limits output power
during fault conditions such as short-circuit or open loop,
reducing component count and system-level load protection
cost. A local supply provided by the IC allows use of a non-
safety graded optocoupler acting as a level shifter to further
enhance line and load regulation performance in buck and
buck-boost converters, if required.
DC
Output
Wide Range
High-Voltage
DC Input
PI-3492-041509
+
+
FB
BP
SD
LinkSwitch-TN