PRODUCT DATA SHEET
PLANAR POWER TRANSFORMER
Features
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Planar windings
4mm height above PCB
Low leakage inductance
High frequency operation
Externally configurable
18–70V input capability
Auxiliary winding
Lead-free (Pb-free)
P6140
Applications
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DC-DC converters
Flyback converters
48V or 24V systems
15V @ 1A output
5V @ 3A output
DESCRIPTION
P6140 is a planar power transformer using
multilayer PCB technology. It is intended for low
profile high frequency discontinuous flyback DC-DC
converters up to 500kHz. With careful design, output
power exceeding 20W is achievable.
P6140 has split primaries that can be configured in
series or parallel for nominal 48V and 24V systems
respectively, with nominal 15V output. The
recommended input voltage range is 18V to 70V.
Additionally, an auxiliary winding is provided on the
primary side.
The contacts to the host circuit board are made
by solder connection to large plated-through
holes in the P6140 PCB, thus ensuring low
resistance connection. The ferrite is intended to
sit within a PCB cut-out, giving a height above
board of 4mm.
P6140 is lead-free (Pb-free) and suitable for
conventional and lead-free processing.
ETALDOC 855/2
Page 1 of 4
August 2004
P6140
SPECIFICATIONS
Electrical
Typical values at T = 25ºC, unless otherwise stated.
Parameter
Primary Inductance
Conditions
100kHz, 100mV
Each primary winding
3-8, 4-7
P6140-1
P6140-2
Leakage Inductance
500kHz, 100mV
(3, 4)-(7, 8); link 1, 2, 9, 10;
link 5, 6
(3+4+5):2
100kHz, 1V
Vout = 15V at Iout = 1A
400kHz
Primaries
3-8, 4-7
Auxiliary
Secondary:
each section
2-1, 1-10, 10-9
Turns Ratio
(3-8):(4-7)
(3-8):(5-6)
(3-8):(9-2)
(9-10):(10-1)
(9-10):(1-2)
Ambient temperature
-40
-40
-
-
+85
+85
ºC
ºC
2.0
2.4
-
2.25
2.8
-
2.50
3.25
100
µH
µH
nH
Min
Typ
Max
Units
Primary/Secondary
voltage isolation
Interwinding capacitance
Total transformer losses
DCR
500
-
-
12
53
3.4
-
325
0.6
16
70
4.5
-
-
-
20
87
5.6
Vrms
pF
W
mΩ
mΩ
mΩ
-
-
-
-
-
1.0
1.0
1.0
1.0
1.0
-
-
-
-
-
-
-
-
-
-
Operating range:
Functional
Storage
Typical Magnetic Core Coefficients
C
1
V
e
l
e
A
e
µ
e
m
Core factor
Effective volume
Effective length
Effective area
Effective permeability
Mass
0.514mm
800mm
20.3mm
3
-1
T
ransformer sc hematic
Fig 1
PRIMARY
3
3T
8
4
PRIMARY
3T
1T
7
5
AUXILIARY 3T
6
9
1T
1
1T
10
SECONDARY
2
39.5mm
123 (P6140-1)
154 (P6140-2)
4.1g
2
ETALDOC 855/2
Page 2 of 4
August 2004
P6140
APPLICATION SCHEMATICS
In the flyback converter topology, the transformer operates as an energy storage element, and the ferrite
core of P6140 is gapped to avoid saturation. The variants P6140-1 and P6140-2 differ in their gap sizes to
suit particular applications and switching frequencies. P6140-1 is recommended for frequencies from
100kHz to 350kHz; P6140-2 is recommended for frequencies from 350kHz to 500kHz
Note that in the discontinuous conduction flyback mode, the output load current flows when the switch is
open. Observe winding polarities.
The auxiliary winding may be used to provide a power rail for switching and control circuits. In the
schematics below, switch drive circuitry and feedback components are omitted for simplicity.
48V operation (38–70V)
For 48V operation the transformer primaries are
connected in series, giving nominal primary
inductance of 9µH (P6140-1) and 11.3µH
(P6140-2), and primary DCR of 33mΩ.
Fig 2 shows a typical schematic with a 15V @ 1A
output. For a 5V output, use the output tap as
shown in fig 3.
48V Operation
Fig 2
3
2
1A
8
+
15V
+
38-70V
–
4
–
9
For 5V output see fig 3
7
SWIT
CH
24V operation (18–38V)
For 24V operation the transformer primaries are
connected in parallel, giving nominal primary
inductance of 2.25µH (P6140-1) and 2.84µH
(P6140-2), and primary DCR of 8mΩ.
Fig 3 shows a typical schematic with a 5V @ 3A
output. For a 15V output, use the output tap as
shown in fig 2.
24V Operation
Fig 3
3
3A
8
+
10
5V
+
18-38V
–
4
–
7
SWIT
CH
9
For 15V outp ut see fig 2
Multiple output
Following the examples given in figs 2 and 3, the
secondary taps can be utilized to provide multiple
output voltages. For example, fig 4 shows a 48V
input flyback converter with +10V and ±5V
outputs. Other combinations are possible.
Multiple output
Fig 4
3
2
+ 10V
8
1
10
0V
+ 5V
+
48V
–
4
0V
7
SWIT
CH
9
-5V
ETALDOC 855/2
Page 3 of 4
August 2004
P6140
CONSTRUCTION
Dimensions
Fig 5
12.0
10 9
8
7
6
25.0
Connections
Fig 6
12.0
9.8
7.0
9.8
4.2
R1
.
20
P6140 - X
7.0
CYYMM
18.0
7.7
5
3
4
Pin 1 ident
2.1
10.0
11.7
Cu P
ADS 2.0 x 2.4 (10x)
Dimensions shown are in millimetres.
Terminal finish is 0.1µm max gold (Au) over nickel (Ni).
ORDERING CODE
P6140- T
Tape and Reel
(400 parts per 13” reel)
Gap variant:
1= 2.25µH (nominal),
frequency 100—350kHz
2= 2.84µH (nominal),
frequency 350—500kHz
Type code
6.0
RECOMMENDED PCB LAYOUT (T VIEW)
OP
ABSOLUTE MAXIMUM RATINGS
(Ratings of components independent of circuit).
Short term isolation voltage
(1s)
Peak primary Current
500Vrms
8A (primaries in
series)
16A (primaries in
parallel; 8A per
primary winding)
V.µs per primary winding
Storage temperature
Magnetic Core temperature
Reflow temperature (10s)
24V.µs
(for B=200mT)
+85ºC
120ºC
260ºC
4.2
CORE
Mounting pads: plated through holes ø1.5
7.9
1 2
9.8
19.2
PCB c utout
7.9
ISO 9001
FM 25326
ETAL Group Oy, Kuormatie 14, FIN-03101, Nummela
Telephone: +358 (0)20 7500 330
Fax: +358 (0)20 7500 333
Website: www.etalgroup.com
Email: etalgroup@egruppen.com
ETALDOC 855/2
Page 4 of 4
August 2004