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July 2010

FAN7621B • Rev. 1.0.1

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

FAN7621B

PFM Controller for Half-Bridge Resonant Converters

Features

 Variable Frequency Control with 50% Duty Cycle

for Half-bridge Resonant Converter Topology

 High Efficiency through Zero Voltage Switching (ZVS)

 Fixed Dead Time (350ns)

 Up to 300kHz Operating Frequency

 Pulse Skipping for Frequency Limit (Programmable)

at Light-Load Condition

 Remote On/Off Control using CON Pin

 Protection Functions: Over-Voltage Protection

(OVP), Overload Protection (OLP), Over-Current

Protection (OCP), Abnormal Over-Current Protection

(AOCP), Internal Thermal Shutdown (TSD)

Applications

 PDP and LCD TVs

 Desktop PCs and Servers

 Adapters

 Telecom Power Supplies

 Video Game Consoles

Description

The FAN7621B is a pulse frequency modulation

controller for high-efficiency half-bridge resonant

converters. Offering everything necessary to build a

reliable and robust resonant converter, the FAN7621B

simplifies designs and improves productivity, while

improving performance. The FAN7621B includes a high-

side gate-drive circuit, an accurate current controlled

oscillator, frequency limit circuit, soft-start, and built-in

protection functions. The high-side gate-drive circuit has

a common-mode noise cancellation capability, which

guarantees stable operation with excellent noise

immunity. Using the zero-voltage-switching (ZVS)

technique dramatically reduces the switching losses and

efficiency is significantly improved. The ZVS also

reduces the switching noise noticeably, which allows a

small-sized Electromagnetic Interference (EMI) filter.

The FAN7621B can be applied to various resonant

converter topologies; such as series resonant, parallel

resonant, and LLC resonant converters.

Related Resources

AN4151 — Half-bridge LLC Resonant Converter Design

using FSFR-series Fairchild Power Switch (FPSTM)

Ordering Information

Part Number Operating Junction

Temperature Package Packaging

Method

FAN7621BSJ -40°C ~ 130°C 16-Lead Small Outline Package (SOP) Tube

FAN7621BSJX Tape & Reel

FAN7621B • Rev. 1.0.1 2

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Application Circuit Diagram

sense

FAN7621B

LVCC

CON

SG PG

CTR

D2 R

Np Ns

KA431

Figure 1. Typical Application Circuit (LLC Resonant Half-Bridge Converter)

Block Diagram

OLP

TSD

LVCC good

Low-Side

Gate Drive

High-Side

Gate Drive

10.0 / 12.5 V

VREF

Internal

Bias

LVCC good

CON

CTR

VAOCP

LVCC

OVP

Time

Delay

Time

Delay

VOCP

-Q

LVCC <5V

Latch

protection

-Q

Auto-restart

protection

0.4 / 0.6 V

5 V

23 V

0.58 V

0.9 V

8.7 / 9.2 V

good

ICTC

1V -Q

F/F

Level-Shift

Balancing

Delay

Shutdown without delay

50ns delay

-1

2ICTC

VREF

ICTC

350ns

Delay

1.5μs

Coun ter (1/4)

LVCC

IOLP

Figure 2. Internal Block Diagram

FAN7621B • Rev. 1.0.1 3

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Pin Configuration

(3) HO

(4) NC

PG (16)

FAN7621B

NC (13)

NC (15)

(5) NC

(6) CON

(7) NC

LO (14)

LVCC (12)

CS (9)

NC (11)

SG (10)

(2) CTR

(1) HVCC

(8) RT

Figure 3. Package Diagram

Pin Definitions

Pin # Name Description

1 HVCC This is the supply voltage of the high-side gate-drive circuit IC.

2 CTR This is the drain of the low-side MOSFET. Typically, a transformer is connected to this pin.

3 HO This is the high-side gate driving signal.

4 NC No connection.

5 NC No connection.

6 CON

This pin is for a protection and enabling/disabling the controller. When the voltage of this pin

is above 0.6V, the IC operation is enabled. When the voltage of this pin drops below 0.4V,

gate drive signals for both MOSFETs are disabled. When the voltage of this pin increases

above 5V, protection is triggered.

7 NC No connection.

8 RT This pin programs the switching frequency. Typically, an opto-coupler is connected to

control the switching frequency for the output voltage regulation.

9 CS

This pin senses the current flowing through the low-side MOSFET. Typically, negative

voltage is applied on this pin.

10 SG This pin is the control ground.

11 NC No connection.

12 LVCC This pin is the supply voltage of the control IC.

13 NC No connection.

14 LO This is the low-side gate driving signal.

15 NC No connection.

16 PG This pin is the power ground. This pin is connected to the source of the low-side MOSFET.

FAN7621B • Rev. 1.0.1 4

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Absolute Maximum Ratings

Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be

operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In

addition, extended exposure to stresses above the recommended operating conditions may affect device reliability.

The absolute maximum ratings are stress ratings only. TA=25°C unless otherwise specified.

Symbol Parameter Min. Max. Unit

VHO High-Side Gate Driving Voltage VCTR-0.3 HVCC V

VLO Low-Side Gate Driving Voltage -0.3 LVCC

LVCC Low-Side Supply Voltage -0.3 25.0 V

HVCC to VCTR High-Side VCC Pin to Center Voltage -0.3 25.0 V

VCTR Center Voltage -0.3 600.0 V

VCON Control Pin Input Voltage -0.3 LVCC V

VCS Current Sense (CS) Pin Input Voltage -5.0 1.0 V

VRT R

T Pin Input Voltage -0.3 5.0 V

dVCTR/dt Allowable Center Voltage Slew Rate 50 V/ns

PD Total Power Dissipation 16-SOP 1.13 W

TJ Maximum Junction Temperature(1) +150

°C

Recommended Operating Junction Temperature(1) -40 +130

TSTG Storage Temperature Range -55 +150 °C

Note:

1. The maximum value of the recommended operating junction temperature is limited by thermal shutdown.

Thermal Impedance

Symbol Parameter Value Unit

θJA Junction-to-Ambient Thermal Impedance 16-SOP 110 ºC/W

FAN7621B • Rev. 1.0.1 5

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Electrical Characteristics

TA=25°C and LVCC=17V unless otherwise specified.

Symbol Parameter Test Conditions Min. Typ. Max.

Unit

Supply Section

ILK Offset Supply Leakage Current HVCC=VCTR 50 μA

IQHVCC Quiescent HVCC Supply Current (HVCCUV+) - 0.1V 50 120 μA

IQLVCC Quiescent LVCC Supply Current (LVCCUV+) - 0.1V 100 200 μA

IOHVCC Operating HVCC Supply Current

(RMS Value)

fOSC=100kHz, VCON > 0.6V,

CLoad=1nF 5 8 mA

No Switching, VCON < 0.4V 100 200 μA

IOLVCC Operating LVCC Supply Current

(RMS Value)

fOSC=100kHz, VCON > 0.6V,

CLoad=1nF 6 9 mA

No Switching, VCON < 0.4V 2 4 mA

UVLO Section

LVCCUV+ LVCC Supply Under-Voltage Positive Going Threshold (LVCC Start) 11.2 12.5 13.8 V

LVCCUV- LVCC Supply Under-Voltage Negative Going Threshold (LVCC Stop) 8.90 10.00 11.10 V

LVCCUVH LVCC Supply Under-Voltage Hysteresis 2.5 V

HVCCUV+ HVCC Supply Under-Voltage Positive Going Threshold (HVCC Start) 8.2 9.2 10.2 V

HVCCUV- HVCC Supply Under-Voltage Negative Going Threshold (HVCC Stop) 7.8 8.7 9.6 V

HVCCUVH HVCC Supply Under-Voltage Hysteresis 0.5 V

Oscillator & Feedback Section

VCONDIS Control Pin Disable Threshold Voltage 0.36 0.40 0.44 V

VCONEN Control Pin Enable Threshold Voltage 0.54 0.60 0.66 V

VRT V-I Converter Threshold Voltage

RT=5.2kΩ

1.5 2.0 2.5 V

fOSC Output Oscillation Frequency 94 100 106 kHz

DC Output Duty Cycle 48 50 52 %

fSS Internal Soft-Start Initial Frequency fSS=fOSC+40kHz, RT=5.2kΩ 140 kHz

tSS Internal Soft-Start Time 2 3 4 ms

Output Section

Isource Peak Sourcing Current HVCC=17V 250 360 mA

Isink Peak Sinking Current HVCC=17V 460 600 mA

tr Rising Time CLoad=1nF, HVCC=17V 65 ns

tf Falling Time 35 ns

VHOH High Level of High-Side Gate Driving

Signal (VHVCC-VHO)

IO=20mA

1.0 V

VHOL Low Level of High-Side Gate Driving

Signal 0.6 V

VLOH High Level of High-Side Gate Driving

Signal (VLVCC-VLO) 1.0 V

VLOL Low Level of High-Side Gate Driving

Signal 0.6 V

FAN7621B • Rev. 1.0.1 6

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Electrical Characteristics (Continued)

TA=25°C and LVCC=17V unless otherwise specified.

Symbol Parameter Test Conditions

Min. Typ. Max.

Unit

Protection Section

IOLP OLP Delay Current VCON=4V 3.8 5.0 6.2 μA

VOLP OLP Protection Voltage VCON > 3.5V 4.5 5.0 5.5 V

VOVP LVCC Over-Voltage Protection LVCC > 21V 21 23 25 V

VAOCP AOCP Threshold Voltage -1.0 -0.9 -0.8 V

tBAO AOCP Blanking Time 50 ns

VOCP OCP Threshold Voltage -0.64 -0.58 -0.52 V

tBO OCP Blanking Time(2) 1.0 1.5 2.0 μs

tDA Delay Time (Low-Side) Detecting from

VAOCP to Switch Off(2) 250 400 ns

TSD Thermal Shutdown Temperature(2) 110 130 150

°C

ISU Protection Latch Sustain LVCC Supply

Current LVCC=7.5V 100 150 μA

VPRSET Protection Latch Reset LVCC Supply

Voltage 5 V

Dead-Time Control Section

DT Dead Time 350 ns

Note:

2. These parameters, although guaranteed, are not tested in production.

FAN7621B • Rev. 1.0.1 7

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Typical Performance Characteristics

These characteristic graphs are normalized at TA=25ºC.

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

Temp (

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Normalized at 25

Figure 4. Low-Side MOSFET Duty Cycle

vs. Temperature

Figure 5. Switching Frequency vs. Temperature

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

Figure 6. High-Side VCC (HVCC) Start vs. Temperature Figure 7. High-Side VCC (HVCC) Stop vs. Temperature

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

Figure 8. Low-Side VCC (LVCC) Start vs. Temperature Figure 9. Low-Side VCC (LVCC) Stop vs. Temperature

FAN7621B • Rev. 1.0.1 8

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Typical Performance Characteristics (Continued)

These characteristic graphs are normalized at TA=25ºC.

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

Figure 10. OLP Delay Current vs. Temperature Figure 11. OLP Protection Voltage vs. Temperature

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

Figure 12. LVCC OVP Voltage vs. Temperature Figure 13. RT Voltage vs. Temperature

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

0.9

0.95

1.05

1.1

-50 -25 0 25 50 75 100

Temp (

Normalized at 25

Figure 14. CON Pin Enable Voltage vs. Temperature Figure 15. OCP Voltage vs. Temperature

FAN7621B • Rev. 1.0.1 9

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Functional Description

1. Basic Operation: FAN7621B is designed to drive

high-side and low-side MOSFETs complementarily with

50% duty cycle. A fixed dead time of 350ns is introduced

between consecutive transitions, as shown in Figure 16.

High-side

MOSFET

gate drive

Low-side

MOSFET

gate drve

Dead t ime

time

Figure 16. MOSFETs Gate Drive Signal

2. Internal Oscillator: FAN7621B employs a current-

controlled oscillator, as shown in Figure 17. Internally,

the voltage of RT pin is regulated at 2V and the charging

/ discharging current for the oscillator capacitor, CT, is

obtained by copying the current flowing out of RT pin

(ICTC) using a current mirror. Therefore, the switching

frequency increases as ICTC increases.

Figure 17. Current Controlled Oscillator

3. Frequency Setting: Figure 18 shows the typical

voltage gain curve of a resonant converter, where the

gain is inversely proportional to the switching frequency

in the ZVS region. The output voltage can be regulated

by modulating the switching frequency. Figure 19 shows

the typical circuit configuration for RT pin, where the

opto-coupler transistor is connected to the RT pin to

modulate the switching frequency.

0.6

0.8

1.0

1.2

1.4

1.6

1.8

Gain

140 150

60 70 80 90 100 110 120 130

Frequency (kHz)

min

normal

max

ISS

Soft-start

Figure 18. Resonant Converter Typical Gain Curve

sense

FAN7621B

CON

SG PG

CTR

max

min

Figure 19. Frequency Control Circuit

The minimum switching frequency is determined as:

min

5.2 100( )

kHz

=× (1)

Assuming the saturation voltage of opto-coupler

transistor is 0.2V, the maximum switching frequency is

determined as:

max

min max

5.2 4.68

()100()

fkHz

=+ × (2)

To prevent excessive inrush current and overshoot of

output voltage during startup, increase the voltage gain

of the resonant converter progressively. Since the

voltage gain of the resonant converter is inversely

ICTC +

1V -Q

F/F

2ICTC

CTC

-Counte

8Gate drive

FAN7621B • Rev. 1.0.1 10

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

proportional to the switching frequency, the soft-start is

implemented by sweeping down the switching frequency

from an initial high frequency (fISS) until the output

voltage is established. The soft-start circuit is made by

connecting R-C series network on the RT pin, as shown

in Figure 19. FAN7621B also has an internal soft-start

for 3ms to reduce the current overshoot during the initial

cycles, which adds 40kHz to the initial frequency of the

external soft-start circuit, as shown in Figure 20. The

initial frequency of the soft-start is given as:

min

5.2 5.2

( ) 100 40 ( )

ISS

kHz

ΩΩ

=+×+ (3)

It is typical to set the initial (soft-start) frequency of two ~

three times the resonant frequency (fO) of the resonant

network.

The soft-start time is three to four times the RC time

constant. The RC time constant is as follows:

SS SS SS

TRC=⋅ (4)

time

Control loop

take over

40kHz

ISS

Figure 20. Frequency Sweeping of Soft-Start

4. Control Pin: The FAN7621B has a control pin for

protection, cycle skipping, and remote on/off. Figure 21

shows the internal block diagram for control pin.

OLP

good

CON

OVP

-Q

Auto-restart

protection

0.4 / 0.6V

23V

OLP

Stop Switching

Figure 21. Internal Block of Control Pin

Protection: When the control pin voltage exceeds 5V,

protection is triggered. Detailed applications are

described in the protection section.

Pulse Skipping: FAN7621B stops switching when the

control pin voltage drops below 0.4V and resumes

switching when the control pin voltage rises above 0.6V.

To use pulse-skipping, the control pin should be

connected to the opto-coupler collector pin. The

frequency that causes pulse skipping is given as:

()

kHz100x

Rk16.4

Rk2.5

maxmin

SKIP

(5)

FAN7621B

CON

SG PG

CTR

max

min

Figure 22. Control Pin Configuration for Pulse

Skipping

Remote On / Off: When an auxiliary power supply is

used for standby, the main power stage using

FAN7621B can be shut down by pulling down the control

pin voltage, as shown in Figure 23. R1 and C1 are used

to ensure soft-start when switching resumes.

Figure 23. Remote On / Off Circuit

5. Protection Circuits: The FAN7621B has several self-

protective functions, such as Overload Protection (OLP),

Over-Current Protection (OCP), Abnormal Over-Current

Protection (AOCP), Over-Voltage Protection (OVP), and

Thermal Shutdown (TSD). OLP, OCP, and OVP are

auto-restart mode protections; while AOCP and TSD are

latch-mode protections, as shown in Figure 24.

FAN7621B • Rev. 1.0.1 11

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Auto-Restart Mode Protection: Once a fault condition

is detected, switching is terminated and the MOSFETs

remain off. When LVCC falls to the LVCC stop voltage of

10.0V, the protection is reset. FAN7621B resumes

normal operation when LVCC reaches the start voltage of

12.5V.

Latch-Mode Protection: Once this protection is

triggered, switching is terminated and the gate output

signals remain off. The latch is reset only when LVCC is

discharged below 5V.

Figure 24. Protection Blocks

Current Sensing Using Resistor: FAN7621B senses

drain current as a negative voltage, as shown in Figure

25 and Figure 26. Half-wave sensing allows low power

dissipation in the sensing resistor, while full-wave

sensing has less switching noise in the sensing signal.

sense

FAN7621B

CON

SG PG

CTR

Figure 25. Half-Wave Sensing

sense

FAN7621B

CON

SG PG

CTR

Figure 26. Full-Wave Sensing

Current Sensing Using Resonant Capacitor Voltage:

For high-power applications, current sensing using a

resistor may not be available due to the severe power

dissipation in the resistor. In that case, indirect current

sensing using the resonant capacitor voltage can be a

good alternative because the amplitude of the resonant

capacitor voltage (Vcrp-p) is proportional to the resonant

current in the primary side (Ipp-p) as:

−

−= (6)

CC good

1 0 / 12.5V

VR E F

Internal

Bias

LVCC good

LVCC

OLP

OV P

-Q

F/F

LVCC <5V

Latch

protection

-Q

F/ F

Aut o-restart

protection

Shutdo

CON

20k

O CP

AOCP

TSD

FAN7621B • Rev. 1.0.1 12

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

To minimize power dissipation, a capacitive voltage

divider is generally used for capacitor voltage sensing,

as shown in Figure 27.

FAN7621B

CON

SG PG

CTR

sense

100

VCr

Vsense

VCr

p-p

Vsense

delay d d

TRC=

sense B

Cr sense B

VCC

−=+2

sense CON

VV=

VCON

Vsense

Figure 27. Current Sensing Using Resonant

Capacitor Voltage

5.1 Over-Current Protection (OCP): When the sensing

pin voltage drops below -0.6V, OCP is triggered and the

MOSFETs remain off. This protection has a shutdown

time delay of 1.5µs to prevent premature shutdown

during startup.

5.2 Abnormal Over-Current Protection: (AOCP): If the

secondary rectifier diodes are shorted, large current with

extremely high di/dt can flow through the MOSFET

before OCP or OLP is triggered. AOCP is triggered

without shutdown delay when the sensing pin voltage

drops below -0.9V. This protection is latch mode and

reset when LVCC is pulled down below 5V.

5.3 Overload Protection (OLP): Overload is defined as

the load current exceeding its normal level due to an

unexpected abnormal event. In this situation, the

protection circuit should trigger to protect the power

supply. However, even when the power supply is in the

normal condition, the overload situation can occur during

the load transition. To avoid premature triggering of

protection, the overload protection circuit should be

designed to trigger only after a specified time to

determine whether it is a transient situation or a true

overload situation. Figure 27 shows a typical overload

protection circuit. By sensing the resonant capacitor

voltage on the control pin, the overload protection can be

implemented. Using RC time constant, shutdown delay

can be also introduced. The voltage obtained on the

control pin is given as:

2( ) pp

CON Cr

Bsense

−

(7)

where VCrp-p is the amplitude of the resonant capacitor

voltage.

5.4 Over-Voltage Protection: (OVP): When the LVCC

reaches 23V, OVP is triggered. This protection is used

when auxiliary winding of the transformer to supply VCC

to the controller is utilized.

5.5 Thermal Shutdown (TSD): If the temperature of the

junction exceeds approximately 130°C, the thermal

shutdown triggers.

FAN7621B • Rev. 1.0.1 13

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

6. PCB Layout Guideline: Duty imbalance problems

may occur due to the radiated noise from main

transformer, the inequality of the secondary-side leakage

inductances of main transformer, and so on. Among

them, it is one of the dominant reasons that the control

components in the vicinity of RT pin are enclosed by the

primary current flow pattern on PCB layout. The direction

of the magnetic field on the components caused by the

primary current flow is changed when the high-and-low

side MOSFET turns on by turns. The magnetic fields with

opposite direction from each other induce a current

through, into, or out of the RT pin, which makes the turn-

on duration of each MOSFET different. It is strongly

recommended to separate the control components in the

vicinity of RT pin from the primary current flow pattern on

PCB layout. Figure 28 shows an example for the duty-

balanced case. The yellow and blue lines show the

primary current flows when the lower-side and higher-

side MOSFETs turns on, respectively. The primary

current does not enclose any component of controller.

In addition, it is helpful to reduce the duty imbalance to

make the loop configured between CON pin and opto-

coupler as small as possible, as shown in the red line in

Figure 28.

Figure 28. Example for Duty Balancing

FAN7621B • Rev. 1.0.1 14

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Typical Application Circuit (Half-Bridge LLC Resonant Converter)

Application Device Input Voltage Range Rated Output Power Output Voltage

(Rated Current)

LCD TV FAN7621B 390VDC

(340~400VDC) 192W 24V-8A

Features

 High efficiency ( >94% at 400VDC input)

 Reduced EMI noise through zero-voltage-switching (ZVS)

 Enhanced system reliability with various protection functions

FAN7621

F101

3.15A/250V

LVcc

CON

SG PG

CTR

HVcc

Vin=340~400Vdc

C301

C101

220uF/450V

Vcc=16~20Vdc

R109

R110

R111

45k

C105

0.33uF

R108

10k

R103 400k

R112

10k

ZD101

6.8V

JP5

R202

D101

1N4937

R113

3.3

R114

3.3

D102

1N4148

D102

1N4148

R115

10k

R116

10k

FCPF11N60F

C106

150nF

R104

5.1k

R105

7.5k R107

7.7k

C107

10uF

C111

680pF

C104

open

C108

12nF

C103

100pF

R102

R101

0.2

JP1, 0

JP2, 0

JP3, 0

JP4, 0

C102

22nF

C110

open

D202

FYPF2010DN

D201

FYPF2010DN

R201

10k

R203

33k

C203

47nF

R205

R204

62k

C204

12nF

R205

C201

2000uF /

35V

C202

2000uF/

35V

EER3542

Figure 29. Typical Application Circuit

FAN7621B • Rev. 1.0.1 15

FAN7621B — PFM Controller for Half-Bridge Resonant Converters

Typical Application Circuit (Continued)

Usually, LLC resonant converters require large leakage inductance value. To obtain a large leakage inductance,

sectional winding method is used.

 Core: EC35 (Ae=106 mm2)

 Bobbin: EC35 (Horizontal)

 Transformer Model Number: SNX-2468-1

EC35

Ns2

Ns1

Figure 30. Transformer Construction

Pins (S → F) Wire Turns Note

Np 6 → 2 0.08φ×88 (Litz Wire) 36

Ns1 12 → 9 0.08φ×234 (Litz Wire) 4 Bifilar Winding

Ns2 10 → 13 0.08φ×234 (Litz Wire) 4 Bifilar Winding

Pins Specifications Remark

Primary-Side Inductance (Lp) 2－6 550μH ± 10% 100kHz, 1V

Primary-Side Effective Leakage (Lr) 2－6 110μH ± 10% Short one of the secondary windings

For more detailed information regarding the transformer, visit http://www.santronics-usa.com/documents.html or

contact sales@santronics-usa.com or +1-408-734-1878 (Sunnyvale, California USA).

PIN #1 IDENT.

A. CONFORMS TO EIAJ EDR-7320

REGISTRATION, ESTABLISHED IN

B. DIMENSIONS ARE IN MILLIMETERS.

C. DIMENSIONS ARE EXCLUSIVE OF BURRS,

MOLD FLASH, AND TIE BAR EXTRUSIONS.

10.30

10.10

5.40

5.20

1.90

1.70

0.51

0.35

1.27 TYP

9.27 TYP

5.01 TYP

1.27

TYP

NOTES:

0.60 TYP

SEE DETAIL A

GAGE PLANE

0.25

SEATING PLANE

0-8° TYP

MIN

0.25 1.25

3.9

7.8

0.47 TYP

2.1 MAX

(2.13 TYP)

0.25

0.15

7° TYP

D. DRAWING FILENAME: MKT-M16Drev5

ALL LEAD TIPS

0.16

0.14

DECEMBER, 1998.

0.2 C B A

0.1 C

0.12 C A

-A-

-B-

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