TOP242-250
®
TOPSwitch-GX
Family
Product Highlights
Lower System Cost, High Design Flexibility
• Extended power range for higher power applications
• No heatsink required up to 34 W using P/G packages
• Features eliminate or reduce cost of external components
• Fully integrated soft-start for minimum stress/overshoot
• Externally programmable accurate current limit
• Wider duty cycle for more power, smaller input capacitor
• Separate line sense and current limit pins on Y/R/F packages
• Line under-voltage (UV) detection: no turn off glitches
• Line overvoltage (OV) shutdown extends line surge limit
• Line feed-forward with maximum duty cycle (DC
MAX
)
reduction rejects line ripple and limits DC
MAX
at high line
• Frequency jittering reduces EMI and EMI filtering costs
• Regulates to zero load without dummy loading
• 132 kHz frequency reduces transformer/power supply size
• Half frequency option in Y/R/F packages for video applications
• Hysteretic thermal shutdown for automatic fault recovery
• Large thermal hysteresis prevents PC board overheating
EcoSmart
–
Energy Efficient
• Extremely low consumption in remote off mode
(80 mW at 110 VAC, 160 mW at 230 VAC)
• Frequency lowered with load for high standby efficiency
• Allows shutdown/wake-up via LAN/input port
Extended Power, Design Flexible,
®
EcoSmart,
Integrated Off-line Switcher
AC
IN
+
DC
OUT
-
D
L
CONTROL
TOPSwitch-GX
S
C
X
F
PI-2632-060200
Figure 1. Typical Flyback Application.
OUTPUT POWER TABLE
PRODUCT
3
230 VAC ±15%
4
Adapter
1
85-265 VAC
Description
TOPSwitch-GX
uses the same proven topology as
TOPSwitch,
cost effectively integrating the high voltage power MOSFET,
PWM control, fault protection and other control circuitry onto
a single CMOS chip. Many new functions are integrated to
reduce system cost and improve design flexibility, performance
and energy efficiency.
Depending on package type, either 1 or 3 additional pins over
the
TOPSwitch
standard DRAIN, SOURCE and CONTROL
terminals allow the following functions: line sensing (OV/UV,
line feed-forward/DC
MAX
reduction), accurate externally set
current limit, remote ON/OFF, synchronization to an external
lower frequency, and frequency selection (132 kHz/66 kHz).
All package types provide the following transparent features:
Soft-start, 132 kHz switching frequency (automatically reduced
at light load), frequency jittering for lower EMI, wider DC
MAX
,
hysteretic thermal shutdown, and larger creepage packages. In
addition, all critical parameters (i.e. current limit, frequency,
PWM gain) have tighter temperature and absolute tolerances
to simplify design and optimize system cost.
TOP242 P or G 9 W
TOP242 R
15 W
TOP242 Y or F 10 W
TOP243 P or G 13 W
TOP243 R
29 W
TOP243 Y or F 20 W
TOP244 P or G 16 W
TOP244 R
34 W
TOP244 Y or F 30 W
TOP245 P or G 19 W
TOP245 R
37 W
TOP245 Y or F 40 W
TOP246 P or G 21 W
TOP246 R
40 W
TOP246 Y or F 60 W
42 W
TOP247 R
TOP247 Y or F 85 W
43 W
TOP248 R
TOP248 Y or F 105 W
44 W
TOP249 R
TOP249 Y or F 120 W
45 W
TOP250 R
TOP250 Y or F 135 W
Open
Open
1
2
Adapter
Frame
Frame
2
15 W
6.5 W
10 W
22 W
11 W
14 W
22 W
7W
14 W
25 W
9W
15 W
45 W
17 W
23 W
45 W
15 W
30 W
28 W
20 W
11 W
50 W
20 W
28 W
65 W
20 W
45 W
30 W
13 W
22 W
57 W
23 W
33 W
85 W
26 W
60 W
34 W
15 W
26 W
64 W
26 W
38 W
125 W
40 W
90 W
70 W
28 W
43 W
165 W
55 W
125 W
75 W
30 W
48 W
205 W
70 W
155 W
79 W
31 W
53 W
250 W
80 W
180 W
82 W
32 W
55 W
290 W
90 W
210 W
Table 1.
Notes:
1.
Typical continuous power in a non-ventilated enclosed
adapter measured at 50
°C
ambient.
2.
Maximum practical continuous
power in an open frame design at 50
°C
ambient. See Key Applications
for detailed conditions.
3.
For lead-free package options, see Part
Ordering Information.
4.
230 VAC or 100/115 VAC with doubler.
November 2005
TOP242-250
Section List
Functional Block Diagram
....................................................................................................................................... 3
Pin Functional Description
...................................................................................................................................... 4
TOPSwitch-GX
Family Functional Description
....................................................................................................... 5
CONTROL (C) Pin Operation.................................................................................................................................. 6
Oscillator and Switching Frequency ........................................................................................................................ 6
Pulse Width Modulator and Maximum Duty Cycle .................................................................................................. 7
Light Load Frequency Reduction ............................................................................................................................ 7
Error Amplifier ......................................................................................................................................................... 7
On-Chip Current Limit with External Programmability ............................................................................................ 7
Line Under-Voltage Detection (UV)......................................................................................................................... 8
Line Overvoltage Shutdown (OV) ........................................................................................................................... 8
Line Feed-Forward with DC
MAX
Reduction .............................................................................................................. 8
Remote ON/OFF and Synchronization ................................................................................................................... 9
Soft-Start ................................................................................................................................................................. 9
Shutdown/Auto-Restart ........................................................................................................................................... 9
Hysteretic Over-Temperature Protection ................................................................................................................. 9
Bandgap Reference .............................................................................................................................................. 10
High-Voltage Bias Current Source ........................................................................................................................ 10
Using Feature Pins
................................................................................................................................................... 10
FREQUENCY (F) Pin Operation ........................................................................................................................... 10
LINE-SENSE (L) Pin Operation ............................................................................................................................ 10
EXTERNAL CURRENT LIMIT (X) Pin Operation .................................................................................................. 11
MULTI-FUNCTION (M) Pin Operation .................................................................................................................. 11
Typical Uses of FREQUENCY (F) Pin
...................................................................................................................... 14
Typical Uses of LINE-SENSE (L) and EXTERNAL CURRENT LIMIT (X) Pins
...................................................... 15
Typical Uses of MULTI-FUNCTION (M) Pin
........................................................................................................... 17
Application Examples
.............................................................................................................................................. 20
A High Efficiency, 30 W, Universal Input Power Supply ........................................................................................ 20
A High Efficiency, Enclosed, 70 W, Universal Adapter Supply .............................................................................. 20
A High Efficiency, 250 W, 250-380 VDC Input Power Supply ............................................................................... 22
Multiple Output, 60 W, 185-265 VAC Input Power Supply .................................................................................... 23
Processor Controlled Supply Turn On/Off ............................................................................................................. 24
Key Application Considerations
............................................................................................................................. 26
TOPSwitch-II
vs.
TOPSwitch-GX
.......................................................................................................................... 26
TOPSwitch-FX
vs.
TOPSwitch-GX
....................................................................................................................... 28
TOPSwitch-GX
Design Considerations ............................................................................................................... 28
TOPSwitch-GX
Layout Considerations ................................................................................................................. 30
Quick Design Checklist ......................................................................................................................................... 32
Design Tools ......................................................................................................................................................... 32
Product Specifications and Test Conditions
......................................................................................................... 33
Typical Performance Characteristics
.................................................................................................................... 40
Part Ordering Information
....................................................................................................................................... 46
Package Outlines
..................................................................................................................................................... 47
2
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11/05
TOP242-250
VC
CONTROL (C)
0
DRAIN (D)
INTERNAL
SUPPLY
ZC
1
SHUNT REGULATOR/
ERROR AMPLIFIER
-
+
+
5.8 V
4.8 V
-
SOFT START
5.8 V
IFB
INTERNAL UV
COMPARATOR
CURRENT
LIMIT
ADJUST
VI
(LIMIT)
SOFT
START
ON/OFF
÷
8
SHUTDOWN/
AUTO-RESTART
-
+
VBG + VT
EXTERNAL
CURRENT LIMIT (X)
STOP LOGIC
CURRENT LIMIT
COMPARATOR
LINE-SENSE (L)
1V
HYSTERETIC
THERMAL
SHUTDOWN
VBG
OV/UV
LINE
SENSE
DCMAX
STOP SOFT-
START
DMAX
DCMAX
CLOCK
HALF
FREQ.
SAW
-
+
S
R
Q
CONTROLLED
TURN-ON
GATE DRIVER
FREQUENCY (F)
OSCILLATOR WITH JITTER
LEADING
EDGE
BLANKING
PWM
COMPARATOR
RE
LIGHT LOAD
FREQUENCY
REDUCTION
SOURCE (S)
PI-2639-060600
Figure 2a. Functional Block Diagram (Y, R or F Package).
VC
CONTROL (C)
0
ZC
1
DRAIN (D)
INTERNAL
SUPPLY
SHUNT REGULATOR/
ERROR AMPLIFIER
+
5.8 V
4.8 V
-
+
-
SOFT START
5.8 V
IFB
VI
(LIMIT)
INTERNAL UV
COMPARATOR
CURRENT
LIMIT
ADJUST
SOFT
START
ON/OFF
÷
8
SHUTDOWN/
AUTO-RESTART
STOP LOGIC
-
+
VBG + VT
CURRENT LIMIT
COMPARATOR
MULTI-
FUNCTION (M)
VBG
OV/UV
HYSTERETIC
THERMAL
SHUTDOWN
LINE
SENSE
DCMAX
STOP SOFT-
START
DMAX
DCMAX
CLOCK
CONTROLLED
TURN-ON
GATE DRIVER
SAW
-
+
S
R
Q
OSCILLATOR WITH JITTER
LEADING
EDGE
BLANKING
PWM
COMPARATOR
RE
LIGHT LOAD
FREQUENCY
REDUCTION
SOURCE (S)
PI-2641-061200
Figure 2b. Functional Block Diagram (P or G Package).
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11/05
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TOP242-250
Pin Functional Description
DRAIN (D) Pin:
High voltage power MOSFET drain output. The internal
start-up bias current is drawn from this pin through a switched
high-voltage current source. Internal current limit sense point
for drain current.
CONTROL (C) Pin:
Error amplifier and feedback current input pin for duty cycle
control. Internal shunt regulator connection to provide internal
bias current during normal operation. It is also used as the
connection point for the supply bypass and auto-restart/
compensation capacitor.
LINE-SENSE (L) Pin: (Y, R or F package only)
Input pin for OV, UV, line feed forward with DC
MAX
reduction,
remote ON/OFF and synchronization. A connection to SOURCE
pin disables all functions on this pin.
EXTERNAL CURRENT LIMIT (X) Pin: (Y, R or F package
only)
Input pin for external current limit adjustment, remote
ON/OFF, and synchronization. A connection to SOURCE pin
disables all functions on this pin.
MULTI-FUNCTION (M) Pin: (P or G package only)
This pin combines the functions of the LINE-SENSE (L) and
EXTERNAL CURRENT LIMIT (X) pins of the Y package
into one pin. Input pin for OV, UV, line feed forward with
DC
MAX
reduction, external current limit adjustment, remote
ON/OFF and synchronization. A connection to SOURCE pin
disables all functions on this pin and makes
TOPSwitch-GX
operate in simple three terminal mode (like
TOPSwitch-II).
Y Package (TO-220-7C)
Tab Internally
Connected to
SOURCE Pin
7
D
5
F
4
S
3
X
2
L
1
C
FREQUENCY (F) Pin: (Y, R or F package only)
Input pin for selecting switching frequency: 132 kHz if
connected to SOURCE pin and 66 kHz if connected to
CONTROL pin. The switching frequency is internally set for
fixed 132 kHz operation in P and G packages.
SOURCE (S) Pin:
Output MOSFET source connection for high voltage power
return. Primary side control circuit common and reference point.
+
R
LS
2 MΩ
V
UV
= I
UV
x R
LS
V
OV
= I
OV
x R
LS
For R
LS
= 2 MΩ
V
UV
= 100 VDC
V
OV
= 450 VDC
DC
MAX
@100 VDC = 78%
DC
MAX
@375 VDC = 38%
C
DC
Input
Voltage
D
L
CONTROL
S
X
R
IL
12 kΩ
For R
IL
= 12 kΩ
I
LIMIT
= 69%
See Figure 54b for
other resistor values
(R
IL
) to select different
I
LIMIT
values
-
Figure 4. Y/R/F Pkg Line Sense and Externally Set Current Limit.
+
V
UV
= I
UV
x R
LS
V
OV
= I
OV
x R
LS
R
LS
2 MΩ
DC
Input
Voltage
For R
LS
= 2 MΩ
V
UV
= 100 VDC
V
OV
= 450 VDC
DC
MAX
@100 VDC = 78%
DC
MAX
@375 VDC = 38%
C
D
M
CONTROL
-
S
PI-2509-040501
Figure 5. P/G Package Line Sense.
P Package (DIP-8B)
G Package (SMD-8B)
M
S
S
C
R Package (TO-263-7C)
F Package (TO-262-7C)
+
For R
IL
= 12 kΩ
I
LIMIT
= 69%
For R
IL
= 25 kΩ
I
LIMIT
= 43%
See Figures 54b, 55b
and 56b for other resistor
values (R
IL
) to select
different I
LIMIT
values.
C
1
2
3
4
8
7
S
S
DC
Input
Voltage
R
IL
D
M
CONTROL
5
D
123 4 5
CL X S F
7
D
PI-2724-010802
-
S
PI-2517-022604
Figure 3. Pin Configuration (top view).
Figure 6. P/G Package Externally Set Current Limit.
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11/05
PI-2629-092203
TOP242-250
TOPSwitch-GX
Family Functional
Description
Frequency (kHz)
Auto-restart
I
CD1
132
I
B
I
L
= 125
µA
Like
TOPSwitch, TOPSwitch-GX
is an integrated switched
mode power supply chip that converts a current at the control
input to a duty cycle at the open drain output of a high voltage
power MOSFET. During normal operation the duty cycle
of the power MOSFET decreases linearly with increasing
CONTROL pin current as shown in Figure 7.
In addition to the three terminal
TOPSwitch
features, such as
the high voltage start-up, the cycle-by-cycle current limiting,
loop compensation circuitry, auto-restart, thermal shutdown,
the
TOPSwitch-GX
incorporates many additional functions that
reduce system cost, increase power supply performance and
design flexibility. A patented high voltage CMOS technology
allows both the high voltage power MOSFET and all the low
voltage control circuitry to be cost effectively integrated onto
a single monolithic chip.
Three terminals, FREQUENCY, LINE-SENSE, and
EXTERNAL CURRENT LIMIT (available in Y, R or F
package) or one terminal MULTI-FUNCTION (available in P
or G package) have been added to implement some of the new
functions. These terminals can be connected to the SOURCE
pin to operate the
TOPSwitch-GX
in a
TOPSwitch-like
three
terminal mode. However, even in this three terminal mode, the
TOPSwitch-GX
offers many new transparent features that do
not require any external components:
1. A fully integrated 10 ms soft-start limits peak currents
and voltages during start-up and dramatically reduces or
eliminates output overshoot in most applications.
2. DC
MAX
of 78% allows smaller input storage capacitor, lower
input voltage requirement and/or higher power capability.
3. Frequency reduction at light loads lowers the switching
losses and maintains good cross regulation in multiple output
supplies.
4. Higher switching frequency of 132 kHz reduces the
transformer size with no noticeable impact on EMI.
5. Frequency jittering reduces EMI.
6. Hysteretic over-temperature shutdown ensures automatic
recovery from thermal fault. Large hysteresis prevents
circuit board overheating.
7. Packages with omitted pins and lead forming provide large
drain creepage distance.
8. Tighter absolute tolerances and smaller temperature
variations on switching frequency, current limit and PWM gain.
The LINE-SENSE (L) pin is usually used for line sensing by
connecting a resistor from this pin to the rectified DC high
voltage bus to implement line overvoltage (OV), under-voltage
(UV) and line feed-forward with DC
MAX
reduction. In this
mode, the value of the resistor determines the OV/UV thresholds
and the DC
MAX
is reduced linearly starting from a line voltage
above the under-voltage threshold. See Table 2 and Figure 11.
I
L
= 190
µA
I
L
< I
L(DC)
30
I
C
(mA)
Auto-restart
I
CD1
78
Duty Cycle (%)
I
B
Slope = PWM Gain
38
I
L
= 125
µA
I
L
< I
L(DC)
10
I
L
= 190
µA
TOP242-5 1.6 2.0
TOP246-9 2.2 2.6
TOP250 2.4 2.7
I
C
(mA)
5.2
5.8
6.5
6.0
6.6
7.3
Note: For P and G packages I
L
is replaced with I
M
.
PI-2633-011502
Figure 7. Relationship of Duty Cycle and Frequency to CONTROL
Pin Current.
The pin can also be used as a remote ON/OFF and a
synchronization input.
The EXTERNAL CURRENT LIMIT (X) pin is usually used
to reduce the current limit externally to a value close to the
operating peak current, by connecting the pin to SOURCE
through a resistor. This pin can also be used as a remote
ON/OFF and a synchronization input in both modes. See
Table 2 and Figure 11.
For the P or G packages the LINE-SENSE and EXTERNAL
CURRENT LIMIT pin functions are combined on one MULTI-
FUNCTION (M) pin. However, some of the functions become
mutually exclusive as shown in Table 3.
The FREQUENCY (F) pin in the Y, R or F package sets the
switching frequency to the default value of 132 kHz when
connected to SOURCE pin. A half frequency option of
66 kHz can be chosen by connecting this pin to CONTROL pin
instead. Leaving this pin open is not recommended.
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