TYN256P Power Integrations Inc., TYN256P Datasheet - Page 7

• Manufacturer Part Number: TYN256P
• Description: Energy Efficient/ Low Power Off-line Switcher
• Manufacturer: Power Integrations Inc.

Figure 12. 5.5 W AC Adaptor with Universal Input (85-265 VAC).
through the TL431 voltage reference for proper regulation.
Capacitor C11 bypasses the TL431 response for improved
ripple performance. Resistor R5 determines the AC gain of the
circuit.
Key Application Considerations
For the most up to date information visit our website
at: www.powerint.com
Design
Output Power
Table 1 shows the practical maximum continuous output power
levels obtainable under following conditions:
1. The minimum DC input voltage is 90 V or higher for 85 VAC
2. A secondary output of 5 V with a Schottky rectifier diode.
3. The P and G packaged parts are board mounted with source
85-265
input or 240 V or higher for 230VAC input or 115 VAC
input with a voltage doubler. This corresponds to a filter
capacitor of 3 F/W for universal input and 1 F/W for 230
or 115 VAC w/doubler input.
pins soldered to sufficient area of copper and the Y packaged
parts are heat sinked sufficiently to keep the die temperature
at or below 100
VAC
1N4005
1N4005
Fusible
10
D3
RF1
D1
1N4005
1N4005
o
C.
D4
D2
10 F
400 V
C1
470 H
4.7 K
10 F
400 V
R1
L1
C2
330 K
1/4 W
R3
TNY256P
1N4937
D5
U1
10 nF
C3
D
S
NC
TinySwitch Plus
EN/UV
BP
2
1
4
The maximum power capability of TinySwitch in a given
application depends on the thermal environment (sealed
enclosure, ventilated, open frame, etc.,), transformer core size
and design (continuous or discontinuous), efficiency required,
minimum specified input voltage, input storage capacitance,
output voltage, output diode forward drop, etc., and can be
different from the values shown in Table 1.
Audible Noise
At loads other than maximum load, the cycle skipping mode
operation used in TinySwitch can generate audio frequency
components in the transformer. This can cause the transformer
to produce audio noise. Transformer audible noise can be
reduced by using appropriate transformer construction
techniques and decreasing the peak flux density. For more
information on audio suppression techniques, please check the
Application Notes section on our web site at www.powerint.com.
Ceramic capacitors that use dielectrics such as Z5U, when used
in clamp and snubber circuits, can also generate audio noise due
to electrostriction and piezo-electric effects. If this is the case,
replacing them with a capacitor having a different type of
dielectric is the simplest solution. Polyester film capacitors and
ceramic capacitors with dielectrics such as NPO or X7R are
good alternatives.
SFH615-2
T1
0.1 F
U2
C4
10
8
MBR360
330 F
16 V
Y1 Safety
C6
2200 pF
D6
C5
100
330 F
TL431CLP
16 V
R5
C7
U3
470
0.1 F
18 H
C11
R9
L3
26.1 K
10 K
R8
R7
220 F
10 V
C8
TNY256
PI-2502-072699
+ 9 V
RTN
0.6 A
8/99
B
7