TFS757-764HG
HiperTFS
™
Family
Combined Two-Switch Forward and Flyback Power Supply Controllers
with Integrated High Voltage MOSFETs
Key Benefits
•
Single chip solution for two-switch forward main and flyback
standby
•
High integration allows smaller form factor and higher power
density designs
•
Incorporates control, gate drivers, and three power
MOSFETS
•
Level shift technology eliminates need for pulse transformer
•
Protection features include: UV, OV, OTP, OCP, and SCP
•
Transformer reset control
•
Prevents transformer saturation under all conditions
•
Allows >50% duty cycle operation
•
Reduces primary side RMS currents and conduction losses
•
Standby supply provides built-in overload power compensation
•
Up to 434 W total output power in a highly compact package
•
Up to 550 W peak
•
High efficiency solution easily enables design to meet
stringent efficiency specifications
•
>90% efficiency at full load
•
No-load regulation and low losses at light-load
•
Simple clip mounting to heat sink without need for insulation pad
•
Halogen free and RoHS compliant
Applications
•
PC
•
Printer
•
LCD TV
•
Video game consoles
•
High-power adapters
•
Industrial and appliance high-power adapters
Output Power Table
Product
TFS757HG
TFS758HG
TFS759HG
TFS760HG
TFS761HG
TFS762HG
TFS763HG
TFS764HG
Table 1.
Two-Switched Forward
380 V
Continuous Continuous
Peak
(25 °C)
(50 °C)
(50 °C)
193 W
163 W
228 W
236 W
200 W
278 W
280 W
235 W
309 W
305 W
258 W
358 W
326 W
276 W
383 W
360 W
304 W
407 W
388 W
327 W
455 W
414 W
344 W
530 W
Flyback
100 V - 400 V
50 °C
20 W
20 W
20 W
20 W
20 W
20 W
20 W
20 W
Output Power Table (See Notes on page 13).
Main Output
HiperTFS
VDDH
HD
HS
L
D
Two-Switch Forward
Transformer
Auxiliary/Standby
Output
DC
Input
FB
RTN
Control,
Gate Drivers,
Level Shift
R
DSB
Flyback
Transformer
FB
EN
EN
FB
BP
EN
G
S
PI-6200-102910
Figure 1.
Simplified Schematic of Two-Switch Forward and Flyback Converter.
www.power.com
April 2015
TFS757-764HG
Section List
Description
.................................................................................................................................................................. 3
Product Highlights
...................................................................................................................................................... 3
Pin Functional Description
......................................................................................................................................... 5
Pin Configuration...................................................................................................................................................... 5
Functional Block Diagram .....................................................................................................................................6-7
Functional Description
............................................................................................................................................... 8
Output Power Table ............................................................................................................................................... 13
Design, Assembly, and Layout Considerations
.................................................................................................... 14
Application Example
................................................................................................................................................. 20
Absolute Maximum Ratings
..................................................................................................................................... 23
Parameter Table ..................................................................................................................................................... 23
Typical Performance Characteristics
.................................................................................................................29-33
Package Details
........................................................................................................................................................ 34
Part Ordering Information.........................................................................................................................................
35
Part Marking Information
......................................................................................................................................... 35
2
Rev. E 04/15
www.power.com
TFS757-764HG
Description
The HiperTFS device family members incorporate both a
high-power two-switch-forward converter and a mid-power
flyback (standby) converter into a single, low-profile eSIP™
power package. The single chip solution provides the controllers
for the two-switch-forward and flyback converters, high- and
low-side drivers, all three of the high-voltage power MOSFETs,
and eliminates the converter’s need for costly external pulse
transformers. The device is ideal for high power applications
that require both a main power converter (two-switch forward)
up to 414 W, and standby converter (flyback) up to 20 W.
HiperTFS includes Power Integrations’ standard set of comprehen-
sive protection features, such as integrated soft-start, fault and
over-load protection, and hysteretic thermal shutdown.
HiperTFS utilizes advanced power packaging technology that
simplifies the complexity of two-switch forward layout, mounting
and thermal management, while providing very high power
capabilities in a single compact package. The devices operate
over a wide input voltage range, and can be used following a
power-factor correction stage such as HiperPFS.
Two-switch-forward power converters are often selected for
applications demanding cost-effective efficiency, fast transient
response, and accurate tolerance to line voltage fluctuation. The
two-switch-forward controller incorporated into HiperTFS
devices improves on the classic topology by allowing operation
considerably above 60% duty cycle. This improvement reduces
RMS currents conduction losses, minimizes the size and cost of
the bulk capacitor, and minimizes output diode voltage ratings.
The advanced design also includes transformer flux reset
control (saturation protection) and charge-recovery switching of
the high-side MOSFET, which reduces switching losses. This
combination of innovations yields an extremely efficient power
supply with smaller MOSFETs, fewer passives and discrete
components, and a lower-cost transformer.
HiperTFS’s flyback standby controller and MOSFET solution is
based on the highly popular TinySwitch™ technology used in
billions of power converter ICs due to its simplicity of operation,
light load efficiency, and rugged, reliable, performance. This
flyback converter can provide up to 20 W of output power and
the built in overload power compensation reduces component
design margin.
•
•
•
•
•
•
•
Programmable line overvoltage (OV) detection; latching and
non-latching
Accurate hysteretic thermal shutdown (OTP)
Accurate selectable current limit (main and standby)
Fully integrated soft-start for minimum start-up stress
Simple fast AC reset
Reduced EMI
•
Synchronized 66 kHz forward and 132 kHz flyback
converters
•
Frequency jitter
Eliminates up to 30 discrete components for higher reliability
and lower cost
Asymmetrical Two-Switch Forward Reduces Losses
•
Allows >50% duty cycle operation
•
Reduces primary side RMS currents and conduction losses
•
Minimizes the size and cost of the bulk capacitor
•
Allows reduced capacitance or longer hold-up time
•
Allows lower voltage output diodes
•
Transformer reset control
•
Prevents transformer saturation under all conditions
•
Extends duty cycle to satisfy AC cycle drop out ride through
•
Duty cycle soft-start with 115% current limit boost
•
Satisfies 2 ms ~ 20 ms start-up with large capacitance at
output
•
Remote ON/OFF function
•
Voltage mode controller with current limit
20 W Flyback with Selectable Power Limit
•
TinySwitch-III based converter
•
Selectable power limit (10 W, 12.5 W, 15 W, or 20 W)
•
Built-in overload power compensation
•
Flat overload power vs. input voltage
•
Reduces component stress during overload conditions
•
Reduces required design margin for transformer and output
diode
•
Output overvoltage (OV) protection with fast AC reset
•
Latching, non-latching, or auto-restart
•
Output short-circuit protection (SCP) with auto-restart
•
Output over-current protection (OCP)
Advanced Package for High Power Applications
•
434 W output power capability in a highly compact package
•
Up to 550 W peak
•
Simple clip mounting to heat sink
•
Can be directly connected to heat sink without insulation pad
•
Provides thermal impedance equivalent to a TO-220
•
Heat slug connected to ground potential for low EMI
•
Staggered pin arrangement for simple routing of board traces
and high-voltage creepage requirements
•
Single power package for two power converters reduces
assembly costs layout size
Product Highlights
Protected Two-Switch Forward and
Flyback Combination Solution
•
Incorporates three high-voltage power MOSFETs, main and
standby controllers, and gate drivers
•
Level shift technology eliminates need for pulse transformer
•
Programmable line undervoltage (UV) detection prevents
turn-off glitches
3
www.power.com
Rev. E 04/15
TFS757-764HG
Typical Two-Switch
Forward
33%
<50%
100%
V
O
+ V
D
/D
MAX
Function
Nominal Duty Cycle
Maximum Duty Cycle
Switch Current (RMS)
Output Catch Diode
HiperTFS
45%
63%
83%
V
O
+ V
D
/D
MAX
Advantages of HiperTFS
Wider duty cycle reduces RMS switch currents by 17%.
Reduces R
DS(ON)
losses by 31%
Lower losses. Wider D
MAX
lowers catch diode rating by
(1-(50%/63%)) = 21% reduction in catch diode voltage
rating
With fast/slow diode combination, allows charge
recovery to limit high-side C
OSS
loss
HiperTFS provides integrated OTP device protection
Improved efficiency. MOSFET R
DS(ON)
sense eliminated
need for sense resistor
Lower cost; component elimination. Removes
high-cost gate-drive transformer (EE10 or toroid)
Saves up to 50 components, depending on specification.
Safer design; easier to design power supply. Flattens
overload output power over line voltages
HiperTFS meets functional safety spacing at package
pins
No SIL (insulation) pad required
Clamp Voltage
Thermal Shutdown
Current Sense Resistor
High-Side Drive
Component Count
TinySwitch Overload Power
Compensation vs. Input Voltage
Package Creepage
Package Assembly
Table 2.
Reset diodes from zero
to V
IN
---
0.5 V drop (0.33
W
at
300 W)
Requires gate-drive
transformer (high cost)
Higher
---
TO-220 = 1.17 mm
2 × TO-220 package, 2
× SIL (insulation)
Reset from zero to
(V
IN
+ 130)
118 °C Shutdown /
55 °C hysteresis
Sense resistor not
required
Built in high-side drive
Lower
Built-in compensation
eSIP16/12 = 2.3 mm/
3.3 mm
1 Package
Summary of Differences Between HiperTFS and Other Typical High Power Supplies.
4
Rev. E 04/15
www.power.com
TFS757-764HG
Pin Functional Description
MAIN DRAIN (D) Pin
Drain of the low-side MOSFET transistor forward converter.
STANDBY DRAIN (DSB) Pin
Drain of the MOSFET of standby power supply.
GROUND (G) Pin
This pin gives a signal current path to the substrate of the
low-side controller. This pin is provided to allow a separate
Kelvin connection to the substrate of the low-side controller to
eliminate inductive voltages that might be developed by high
switching currents in the SOURCE pin. The GROUND pin is
not intended to carrier high currents, instead it is intended as a
voltage-reference connection only.
SOURCE (S) Pin
SOURCE pin that is common to both the standby and main
supplies.
RESET (R) Pin
This pin provides information to limit the maximum duty cycle as a
function of the current fed into the RESET pin during the off-time
of the main converter MOSFET. This pin can also be pulled up to
bypass to signal remote ON/OFF of the main converter only.
ENABLE (EN) Pin
This is the ENABLE pin for the standby controller. Prior to the
start-up a resistor connected from ENABLE to BYPASS, can be
detected to select one of several internal current limits.
LINE-SENSE (L) Pin
This pin provides input bulk voltage line-sense function. This
information is used by the undervoltage and overvoltage
detection circuits for both main and standby. The pin can also
be pulled up to BYPASS or be pulled down to SOURCE to
implement a remote ON/OFF of both standby and main
supplies simultaneously. The LINE-SENSE pin works in
conjunction with the RESET pin to implement a duty-cycle limit
function. Also the LINE-SENSE pin compensates the value of
standby current limit so as to flatten the output overload
response as a function of input voltage.
FEEDBACK (FB) Pin
This pin provides feedback for the main two transistor forward
converter. An increase in current sink from FEEDBACK pin to
ground, will lead to a reduction in operating duty cycle. This pin
also selects the main device current limit at start-up (in a similar
manner to ENABLE pin).
Figure 2.
Pin Configuration.
BYPASS (BP) Pin
This is the decoupled operating voltage pin for the low-side
controller. At start-up the bypass capacitor is charged from an
internal device current source. During normal operation the
capacitor voltage is maintained by drawing current from the
low-side bias winding on the standby power supply. This pin is
also used to implement remote ON/OFF for the main controller.
This is done by driving extra current into the BYPASS pin when
we want to turn-on the Main controller. The BYPASS pin also
implements a latch-off function to disable standby and main
when the BP pin current exceeds latching threshold. Latch is
reset when LINE-SENSE pin falls below UV (off) standby
threshold.
HIGH-SIDE OPERATING VOLTAGE (VDDH) Pin
This is the high-side bias (VDD) of approximately 11.5 V. This
voltage is maintained with current from a high-side bias winding
on the main transformer and/or from a bootstrap diode from the
low-side standby bias supply.
HIGH-SIDE SOURCE (HS) Pin
SOURCE pin of the high-side MOSFET.
HIGH-SIDE DRAIN (HD) Pin
DRAIN pin of the high-side MOSFET. This MOSFET is floating
with respect to low-side source and ground.
H Package (eSIP-16/12)
Exposed Metal
(On Edge)
Internally
Connected
1
D
3
DSB
5 6 7 8 9 10 11 13 14 16
BP
FB
L
EN
R
S
G
HS
VDDH
HD
HD
HD
HS
S
S
Exposed Pad
(Backside) Internally
Connected to SOURCE
Pin (see eSIP-16B
Package Drawing)
PI-5290-110510
5
www.power.com
Rev. E 04/15
