TOP234G Power Integrations, TOP234G Datasheet - Page 15
![IC OFFLINE SWIT OVP UVLO 8SMD](/photos/7/32/73209/596-8-bsmd_sml.jpg)
TOP234G
Manufacturer Part Number
TOP234G
Description
IC OFFLINE SWIT OVP UVLO 8SMD
Manufacturer
Power Integrations
Series
TOPSwitch®-FXr
Type
Off Line Switcherr
Datasheet
1.TOP234YN.pdf
(36 pages)
Specifications of TOP234G
Output Isolation
Isolated
Frequency Range
66 ~ 132kHz
Voltage - Output
700V
Power (watts)
30W
Operating Temperature
-40°C ~ 150°C
Package / Case
8-SMD Gull Wing, 7 Leads
Output Voltage
12 V
Input / Supply Voltage (max)
265 VAC
Input / Supply Voltage (min)
85 VAC
Duty Cycle (max)
78 %
Switching Frequency
132 KHz
Supply Current
1.5 mA
Operating Temperature Range
- 40 C to + 150 C
Mounting Style
SMD/SMT
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
TOP234GN
Manufacturer:
PowerInt
Quantity:
350
Part Number:
TOP234GN
Manufacturer:
POWER
Quantity:
20 000
Part Number:
TOP234GN-TL
Manufacturer:
POWER
Quantity:
20 000
35 W Multiple Output Power Supply
Figure 25 shows a five output, 35 W, secondary regulated
power supply utilizing a TOP233 for multiple output applications
such as set-top box, VCR, DVD, etc. The circuit shown is
designed for a 230 VAC input but can be used over the universal
range at a derated output power of 25 W. Alternatively, a
doubler input stage can be used at 100 or 115 VAC for the full
power rating of 35 W. TOPSwitch-FX provides several
advantages in the above mentioned applications.
A single line sense resistor R1 (2 MΩ) implements an under-
voltage detect (at 100 V), over-voltage shutdown (at 450 V) and
line feed forward with DC
voltage detect ensures that the outputs are glitch free on power
down. The over-voltage shutdown turns off the TOPSwitch-FX
MOSFET above 450 V on the DC input rail, eliminating
reflected voltage and leakage inductance spikes, and hence,
extending the surge withstand to the 700 VDC rating of the
MOSFET. This feature prevents field failures in countries
where prolonged line voltage surges are common.
This design also takes advantage of soft-start and higher operating
frequency to reduce transformer size. A snubber circuit (R4,
C4) is used to slowdown dv/dt of the switching waveform
minimizing radiated video noise that could interfere with TV
reception. The half frequency option of the TOPSwitch-FX can
be used by connecting the FREQUENCY pin to the CONTROL
Figure 25. 35 W Set-Top Box Power Supply.
250 VAC
0.1 µF
CX1
J1
N
L
20 mH
L1
3.15 A
275 V
RV1
F1
400 V
BR1
400 V
33 µF
C1
P6KE200
TOP233Y
47 pF
2 kΩ
MAX
UF4007
R4
C4
VR1
D1
U1
reduction features. Under-
D
S
CONTROL
CONTROL
M
F
1/2 W
2.2 nF
2 MΩ
TOPSwitch-FX
CY1
R1
C
T1
47 µF
6.8 Ω
R5
C5
1N5819
MUR120
UF5402
MBR1045
D12
BYW29-
D9
D8
D11
D10
100
1N4148
330 µF
D2
10 V
C18
100 nF
pin instead of the SOURCE pin in video noise sensitive
applications to allow for heavier snubbing without significant
impact on efficiency.
This design achieves ±5% load regulation on 3.3 V and 5 V
outputs using dual sensed optocoupler feedback through resistors
R9, R10 and R11. Other output voltages are set by the transformer
turns ratio. Output voltage on the low power -5 V output is shunt
regulated by resistor R12 and Zener diode VR2. Dummy load
resistor R13 is required to maintain regulation of the 30 V
output under light load conditions. Compensation of the TL431
(U3) is achieved with resistor R8 and capacitor C7. Primary
side compensation and auto-restart frequency are determined
by resistor R5 and capacitor C5. Second stage LC post-filtering
is used on the 3.3 V, 5 V and 18 V high power outputs (L2, L3,
L4 and C13, C15, C17) for low ripple. Full load operating
efficiency exceeds 75% across the AC input range. Primary
clamp components VR1 and D1 limit peak drain voltage to a
safe value.
The frequency jittering in TOPSwitch-FX helps reduce EMI,
maintaining emissions below CISPR 22 (FCC B) levels through
proper choice of Y1 capacitor (CY1) and input filtering elements
(CX1, L1). To minimize coupling of common mode transients
to the TOP233, Y1 capacitor is tied to the positive input DC rail.
Lightning strike immunity to 3 kV is attained with the addition
of a 275 V MOV (RV1).
100 µF
50 V
C6
C10
220 µF
25 V
C12
R12
5 Ω
1000 µF
25 V
22 µF
C14
1000 µF
C8
25 V
C16
LTV817
51 Ω
R6
U2
U3
TL431CLP
1N5231
VR2
10 Ω
R8
510 Ω
3.3 µH
R7
100 µF
L4
10 V
C17
0.1 µF
3.3 µH
C7
L3
100 µF
10 V
C19
3.3 µH
10.0 kΩ
9.53 kΩ
L2
R11
R9
100 µF
10 V
C15
15.0 kΩ
TOP232-234
R10
100 µF
25 V
C13
1 µF
50 V
C11
PI-2536-040401
7/01
30 V
@ 100 mA
18 V
@ 550 mA
24 kΩ
-5 V
@ 100 mA
3.3 V
@ 3 A
R13
B
5 V
@ 2.5 A
RTN
15