A Product Line of
Diodes Incorporated
APR34309C
SECONDARY SIDE SYNCHRONOUS RECTIFICATION SWITCHER
Description
APR34309C is a secondary side Combo IC, which combines an N-
Channel MOSFET and a driver circuit designed for synchronous
rectification (SR) in DCM operation. It also integrates output voltage
detect function for primary side control system.
Pin Assignments
(Top View)
DRISR
1
2
3
4
8
7
6
5
GND
NEW PRODUCT
The N-Channel MOSFET has been optimized for low gate charge,
low R
DS(ON)
, fast switching speed and body diode reverse recovery
performance.
The synchronous rectification can effectively reduce the secondary
side rectifier power dissipation and provide high performance solution.
By sensing MOSFET drain-to-source voltage, APR34309C can output
ideal drive signal with less external components. It can provide high
performance solution for 5V output voltage application.
Same as AP4341, APR34309C detects the output voltage and
provides a periodical signal when the output voltage is lower than a
certain threshold. By fast response to secondary side voltage,
APR34309C can effectively improve the transient performance of
primary side control system.
The APR34309C is available in SO-8EP package.
VDET
GND
AREF
GND
VCC
DRAIN
Note: The DRAIN pin of internal MOSFET is
exposed PAD, which
is at the bottom
of IC (the
dashed box). The secondary current should flow from GND(pin 6,7,8) to
this exposed PAD.
SO-8EP
Applications
•
•
Adapters/Chargers for Cell/Cordless Phones, ADSL Modems, MP3
and Other Portable Apparatus
Standby and Auxiliary Power Supplies
Features
•
Synchronous Rectification for DCM Operation Flyback
•
Eliminate Resonant Ring Interference
•
Fast Detector of Supply Voltages
•
Fewest External Components
Totally Lead-free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
Typical Applications Circuit
C21
+
C23
R21
C22
+
APR34309C
R23
DRAIN DRAIN GND
DRISR
VDET
GND
GND
VCC
R24
C
AREF
AREF
C24
R
AREF
APR34309C
Document number: DS37492 Rev. 5 - 2
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www.diodes.com
June 2015
© Diodes Incorporated
A Product Line of
Diodes Incorporated
APR34309C
Pin Descriptions
Pin Number
1
2
3
Pin Name
DRISR
VDET
AREF
VCC
DRAIN
GND
DRAIN
Synchronous rectification MOSFET drive.
Synchronous rectification sense input and dynamic function output, connected to DRAIN
through a resistor.
Program a voltage reference with a resistor from AREF to GND, to enable synchronous
rectification MOSFET drive signal.
Power supply, connected with system output.
Drain pin of internal MOSFET. The Drain voltage signal can obtain from this pin.
Source pin of internal MOSFET, connected to Ground.
Drain pin of internal MOSFET.
The secondary current should flow from GND (pin 6.7.8)
to this DRAIN pad.
Function
NEW PRODUCT
4
5
6,7,8
Exposed PAD
Functional Block Diagram
VCC
4
V
REF
Integrator
(V
DET
-V
CC
)*t
ONP
I
AREF
VDET
I
OVP
Dynamic
OVP
t
ONPDET
Counter
OSC
AREF
DRISR
3
1
SRDRIVER
6,7,8
GND
DRAIN
5, EP
2
VDET
APR34309C
Document number: DS37492 Rev. 5 - 2
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June 2015
© Diodes Incorporated
A Product Line of
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APR34309C
Absolute Maximum Ratings
(Note 4)
Symbol
V
CC
V
DET,
V
DRAIN
V
AREF,
V
DRISR
I
D
Supply Voltage
Voltage at VDET, DRAIN Pin
Voltage at AREF, DRISR Pin
Continuous Drain Current
Pulsed Drain Current
Power Dissipation at T
A
=+25º
C
Thermal Resistance (Junction to Ambient)
(Note 5)
Thermal Resistance (Junction to Case)
(Note 5)
Operating Junction Temperature
Storage Temperature
Lead Temperature (Soldering, 10 sec)
Charge Device Model
Parameter
Value
-0.3 to 7.5
-2 to 50
-0.3 to 6
20
80
2.2
56
12
+150
-65 to +150
+300
1000
Unit
V
V
V
A
A
W
º
C/W
º
C/W
º
C
º
C
º
C
V
NEW PRODUCT
I
DM
P
D
θ
JA
θ
JC
T
J
T
STG
T
LEAD
ESD
Notes:
4. Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “Recommended Operating Conditions” is not implied.
Exposure to “Absolute Maximum Ratings” for extended periods may affect device reliability.
5. FR-4 substrate PC board, 2oz copper, with 1 inch
2
pad layout.
Recommended Operating Conditions
Symbol
V
CC
T
A
Supply Voltage
Ambient Temperature
Parameter
Min
3.3
-40
Max
6
+85
Unit
V
º
C
APR34309C
Document number: DS37492 Rev. 5 - 2
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A Product Line of
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APR34309C
Electrical Characteristics
Symbol
Supply Voltage ( VCC Pin )
I
STARTUP
I
OP
V
STARTUP
Startup Current
Operating Current
Startup Voltage
UVLO
V
CC
=V
STARTUP
-0.1V
VDET pin floating
V
CC
=V
TRIGGER
+20mV
–
–
–
40
2.6
2.3
100
100
3.1
2.8
150
150
3.4
3.1
μA
μA
V
V
(@T
A
= +25° V
CC
=5V, unless otherwise specified.)
C,
Parameter
Conditions
Min
Typ
Max
Unit
NEW PRODUCT
–
Dynamic Output Section/Oscillator Section
V
TRIGGER
–
t
OSC
I
TRIGGER
t
DIS
V
DIS
I
DIS
V
DIS
-V
TRIGGER
V
OVP
I
OVP
Internal Trigger Voltage
Duty Cycle
Oscillation Period
Internal Trigger Current
Minimum Period
Discharge Voltage
Discharge Current
Trigger Discharger Gap
Overshoot Voltage for Discharge
Overshoot Current for Discharge
–
–
V
CC
=5V
V
CC
=V
TRIGGER
, VCC/VDET pin is
separately connected to a 20Ω
resistor
–
–
V
CC
=V
DIS
+0.1V
–
–
V
CC
=V
OVP
+0.1V, VCC pin is
connected to a 20Ω resistor
–
–
From V
THON
to V
DRISR
=1V
From V
THOFF
to V
DRISR
=3V
From 1V to 3V, C
L
=4.7nF
From 3V to 1V, C
L
=4.7nF
(V
DET
-V
CC
)*t
ONP
= 25Vµs
(V
DET
-V
CC
)*t
ONP
= 50Vµs
Drive Output Voltage
SR Minimum Operating Voltage
(Note 6)
Added OVP Discharge Time
(Note 7)
V
CC
=5V
–
–
(V
DET
-V
CC
)*t
ONP
= 25Vµs
5.1
4
18
30
18
5.13
1.5
30
5.64
40
5.15
15
30
60
30
5.3
3
110
5.74
–
5.2
18
37.5
80
37.5
5.38
4.5
–
5.84
100
V
%
μs
mA
ms
V
mA
mV
V
mA
Synchronous Voltage Detect
V
THON
V
THOFF
t
DON
t
DOFF
t
RG
t
FG
t
LEB_S
t
LEB_L
V
DRISR_HIGH
V
S_MIN
t
OVP_LAST
Kqs
Notes:
Gate Turn-on Threshold
Gate Turn-off Threshold
Turn-on Delay Time
Turn-off Propagation Delay Time
Gate Turn-on Rising Time
Gate Turn-off Falling Time
Minimum On Time
0
-13
–
–
–
–
0.9
–
3.7
–
–
0.325
–
-9
70
100
50
50
1.8
–
–
–
2.0
–
1
-5
130
150
100
100
2.7
6.5
–
4.5
–
0.515
V
mV
ns
ns
ns
ns
μs
V
V
ms
mA*μs
6. This item specifies the minimum SR operating voltage of V
IN_DC
, V
IN_DC
≥N
PS
*V
S_MIN.
7. This item is used to specify the value of R
AREF
.
APR34309C
Document number: DS37492 Rev. 5 - 2
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June 2015
© Diodes Incorporated
A Product Line of
Diodes Incorporated
APR34309C
Electrical Characteristics
MOSFET Static Characteristics
Parameters
Drain to Source Breakdown
Voltage
Gate Threshold Voltage
Symbol
V
DSS(BR)
V
GS(TH)
I
DSS
I
GSS
R
DS(ON)
Conditions
V
GS
=0V, I
D
=0.25mA
V
DS
=V
GS
, I
D
=0.25mA
V
DS
=50V, V
GS
=0V
V
GS
=10V, V
DS
=0V
V
GS
=4.5V, I
D
=3A
Min
50
0.7
–
–
–
Typ
–
1.3
–
–
8
Max
100
2
1
±100
–
Unit
V
V
µA
nA
mΩ
(@T
A
=+25° unless otherwise specified. Cont.)
C,
NEW PRODUCT
Zero Gate Voltage Drain
Current
Gate to Source Leakage
Current
Drain to Source On-state
Resistance
MOSFET Dynamic Characteristics
Parameters
Input Capacitance
Output Capacitance
Reverse Transfer Capacitance
Gate to Source Charge
Gate to Drain Charge (Miller
Charger)
Total Gate Charge
Gate Resistance
Symbol
C
iss
C
oss
C
rss
Q
gs
Q
gd
Q
g
R
g
V
GS
=0V to 10V, V
DD
=25V,
I
D
=15A
V
GS
=4.5V
–
V
GS
=0V, V
DS
=25V, f=1MHz
Conditions
Min
–
–
–
–
–
–
–
Typ
1872
506
43
3.1
4.8
15
1.8
Max
–
–
–
–
–
–
–
Ω
nC
pF
Unit
APR34309C
Document number: DS37492 Rev. 5 - 2
5 of 13
www.diodes.com
June 2015
© Diodes Incorporated
