®
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
integrated/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
200mW 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 & VCRs
• Operates with optocoupler or bias winding feedback
+
+
DC Output
–
Wide-Range
HV DC Input
D
®
TinySwitch
EN
BP
S
–
PI-2178-022699
Figure 1. Typical Standby Application.
TinySwitch
SELECTION GUIDE
ORDER
PART
NUMBER
TNY253P
TNY253G
TNY254P
TNY254G
TNY255P
TNY255G
Recommended Range
for Lowest System Cost*
PACKAGE
230 VAC or
115 VAC
w/Doubler
85-265
VAC
DIP-8
SMD-8
DIP-8
SMD-8
DIP-8
SMD-8
0-4 W
0-2 W
2-5 W
4-10 W
1-4 W
3.5-6.5 W
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
265VAC input. A simple ON/OFF control scheme also
eliminates the need for loop compensation.
The TNY253 and TNY254 switch at 44 kHz to minimize EMI
and to allow a simple snubber clamp to limit DRAIN spike
Table 1. *Please refer to the Key Application Considerations section
for details.
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 2.5W.
TNY255 uses higher switching rate of 130kHz 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
spaced bobbin can be used for applications under 2.5W.
Absence of a bias winding eliminates the need for taping/
margins in most applications, when triple insulated wire is used
for the secondary. This simplifies the transformer construction
and reduces cost.
July 2001
POWERINT [ POWER INTEGRATIONS, INC. ]
