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TNY253/254/255 TinySwitch™ Family
Energy Efficient, Low Power Off-line Switchers
Product Highlights
Lowest Cost, Low Power Switcher Solution • Lower cost than RCC, discrete PWM and other integrat-
ed/hybrid solutions • Cost effective replacement for bulky linear adapters • Lowest component count • Simple ON/OFF control – no loop compensation devices • No bias winding – simpler, lower cost transformer • Allows simple RC type EMI filter for up to 2 W from
universal input or 4 W from 115 VAC input
Extremely Energy Efficient • Consumes only 30/60 mW at 115/230 VAC with no load • Meets Blue Angel, Energy Star, Energy 2000 and 200 mW
European cell phone requirements for standby • Saves $1 to $4 per year in energy costs (at $0.12/kWHr)
compared to bulky linear adapters • Ideal for cellular phone chargers, standby power supplies for
PC, TV and VCR, utility meters, and cordless phones.
High Performance at Low Cost • High-voltage powered – ideal for charger applications • Very high loop bandwidth provides excellent transient
response and fast turn on with practically no overshoot • Current limit operation rejects line frequency ripple • Glitch free output when input is removed • Built-in current limit and thermal protection • 44 kHz operation (TNY253/4) with snubber clamp
reduces EMI and video noise in TVs and VCRs • Operates with optocoupler or bias winding feedback
Description
The TinySwitch family uses a breakthrough design to provide the lowest cost, high efficiency, off-line switcher solution in the 0 to 10 W range. These devices integrate a 700 V power MOSFET, oscillator, high-voltage switched current source, current limit and thermal shutdown circuitry. They start-up and run on power derived from the DRAIN voltage, eliminating the need for a transformer bias winding and the associated circuitry. And yet, they consume only about 80 mW at no load, from 265 VAC input. A simple ON/OFF control scheme also eliminates the need for loop compensation.
+
Wide-Range High-Voltage
DC Input
–
TinySwitch
D EN BP
S
Figure 1. Typical Standby Application.
+ DC Output
–
PI-2178-022699
TinySwitch Selection Guide
ORDER PART
NUMBER
TNY253P TNY253G TNY254P TNY254G TNY255P TNY255G
PACKAGE
DIP-8 SMD-8 DIP-8 SMD-8 DIP-8 SMD-8
Recommended Range for Lowest System Cost*
230 VAC or 115 VAC
w/Doubler
85-265 VAC
0-4 W
0-2 W
2-5 W
1-4 W
4-10 W 3.5-6.5 W
Table 1. *Please refer to the Key Application Considerations section for details.
The TNY253 and TNY254 switch at 44 kHz to minimize EMI and to allow a simple snubber clamp to limit DRAIN spike voltage. At the same time, they allow use of low cost EE16 core transformers to deliver up to 5 W. The TNY253 is identical to TNY254 except for its lower current limit, which reduces output short-circuit current for applications under 2.5 W. TNY255 uses higher switching rate of 130 kHz to deliver up to 10 W from the same low cost EE16 core for applications such as PC standby supply. An EE13 or EF13 core with safety .