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PT5634A
Power Factor Correction Control IC
DESCRIPTION
The PT5634A is a Power Factor Correction control IC
for electronic ballast and switching mode power supply
application. With a wide bandwidth error amplifier and a
wide linear operating range multiplier, the PT5634A is
available to operate in Critical Conduction Mode and
implement a high PF and excellent THD in wide input
voltage application. Furthermore, PT5634A provides a
low start-up current and operating current, a precise
over-voltage protection and the disable function.
FEATURES







Critical Conduction Mode (CRM) control
Very low start-up current (30μA)
Precise reference voltage (±1%)
Precise adjustable output over-voltage protection
Restart timer
Leading edge blocking time
Disable function
APPLICATIONS


Electronic ballast
AC-DC adaptor and switching mode power supply
BLOCK DIAGRAM
Tel: 886-66296288‧Fax: 886-29174598‧ http://www.princeton.com.tw‧2F, 233-1, Baociao Road, Sindian Dist.,New Taipei City 23145, Taiwan
PT5634A
TYPICAL APPLICATION
V1.0
2
July 2014
PT5634A
ORDER INFORMATION
Valid Part Number
PT5634A-S
Package Type
8 Pins, SOP, 150mil
Top Code
PT5634A-S
PIN CONFIGURATION
PIN DESCRIPTION
Pin Name
INV
COMP
MULT
CS
ZCD
GND
GD
VCC
V1.0
Description
Error amplifier inverting input
Error amplifier compensation
Multiplier input
Current sense
Zero current detection
System ground
Gate driver output
IC power supply
3
Pin No.
1
2
3
4
5
6
7
8
July 2014
PT5634A
FUNCTION DESCRIPTION
UNDER VOLTAGE LOCK OUT AND VOLTAGE CLAMP
The turn-on threshold of Under-Voltage Lock-Out (UVLO) circuit is 12.5V, and the turn-off threshold is 10V. In UVLO
mode, PT5634A is locked and the start-up current is very low (30μA, typ.).
A VCC voltage clamp is added to pervert the device from destroy by over-voltage. When the voltage of VCC reaches the
clamp threshold, there is an internal additional current to clamp the VCC voltage.
ERROR AMPLIFIER
The non-inverting input of error amplifier (EA) is connected to the internal reference 2.5V, and the inverting input INV is
connected to the external resistor divider. In typical application, with an external capacitor between INV pin and COMP
pin (the output of EA), the EA acts an integrator which detects the PFC output and provides a negative feedback.
Generally, the bandwidth of the integrator is designed below 20Hz in order to suppress the 100Hz rippers of PFC output.
Additionally, the disable function is built in. When the INV voltage is pulled down below 0.2V, PT5634A will enter disable
mode and shut down the driver output GD.
OVER-VOLTAGE REGULATOR AND OVER-VOLTAGE PROTECTION
The response speed of the low bandwidth integrator is slow and the PFC output could not be stabilized in the conditions
of the input line voltage increasing or the load decreasing abruptly. PT5634A provides an over-voltage regulator and an
over-voltage protection to limit the PFC output.
The over-voltage regulator and the over-voltage protection are implemented by detecting the sink current of COMP.
During stable operation, there is not current flowing in the external capacitor (C4) between INV and COMP. However,
When the PFC output increases abruptly, the current in R6 and R7 increases, but the INV voltage is stuck in 2.5V and the
current in R8 does not change. The increment current in R6 and R7 flows through the capacitor C4 and flows into COMP.
When the current flowing into COMP reaches to 24μA, the over-voltage regulator is triggered and decreases the
multiplier output rapidly, and then the turn-on time of Power MOSFET decreases and the energy from input line to PFC
output decreases. When the current flowing into COMP reaches to 27uA, the over-voltage protection is triggered and
shut down the driver output GD. The over-voltage protection has a 20μA hysteresis. In application, the over-voltage
increment of PFC output is set by adjusting the valve of R6 and R7.
There is a static OVP in COMP which threshold is 2.2V. If the over-voltage protection is triggered, PT5634A will be
un-locked in the conditions that the COMP sinking current is below 7μA and the COMP voltage is bigger than 2.2V.
MULTIPLIER
The multiplier has tow inputs: COMP pin and MULT pin. The MULT pin detects the rectifier line voltage through an
external resistor divider. In stable operation, because the COMP voltage is a constant in an AC cycle, the multiplier
output is proportional to the MULT voltage, as well as the rectifier line voltage. The multiplier, with a wide linear operating
range, has a good linearity in 85V~265V AC input voltage range.
The multiplier output is internally clamped to 1.08V in order to limit the PFC current and protect the Power MOSFET.
CURRENT SENSE
PT5634A connects CS pin to a sense resistor which is connected between the source of Power MOSFET and ground.
An internal comparator, connecting to the multiplier output as a reference, detects the CS voltage which is proportional to
PFC current. Via detecting the PFC current cycle by cycle, the PFC current is proportional to the multiplier output, as well
as the rectifier line voltage. The PFC current is proportional to the input line current too. So, the input line current follows
the input line voltage and the PF is nearly 1.
V1.0
4
July 2014
PT5634A
There is a turn-on spike in CS pin when the Power MOSFET is switched on, which will disturb the PFC current detection.
PT5634A inserts a Leading Edge Blank time at the rise edge of GD. The LEB circuit, instead of the conventional RC filter,
can minimize the propagation delay.
ZERO CURRENT DETECTION
In CRM control, it needs to sense the PFC inductor current. When the PFC current decreases to zero, the zero current
detection circuit outputs the set signal to the driver output GD and starts a switch cycle. In application circuit, if the energy
stored in the inductor releases fully, the drain voltage of the power MOSFET and the ZCD voltage begin to decrease. As
soon as the ZCD voltage decreases below the threshold 0.7V, the GD is set to “high” and starts a new cycle. The zero
current switch of the MOSFET reduces the power dissipation and the switching noise.
V1.0
5
July 2014
PT5634A
ABSOLUTE MAXIMUM RATINGS
Absolute maximum ratings indicate sustained limits beyond which damage to the device may occur. All voltage
parameters are absolute voltages referenced to GND.
Parameter
Symbol
Min.
Max.
Unit
(see Note)
Power supply
VCC
25
V
INV input voltage
VINV
-0.3
7.0
V
COMP input voltage
VCOMP
-0.3
7.0
V
MULT input voltage
VMULT
-0.3
7.0
V
CS input voltage
VCS
-0.3
7.0
V
ZCD input voltage
VZCD
-0.3
7.5
V
ZCD output current
GD maximum output voltage
GD maximum output current
Operating temperature
Junction temperature operating range
Storage temperature
IZCD
VGD
IOMAX
Topr
Tj
Tstg
-3
-0.3
-400
-40
-40
3
VCC+0.3
400
+125
+125
+150
mA
V
mA
℃
℃
Note: A clamp circuit is integrated. When the VCC voltage exceeds 25V, the clamp circuit pulls down a large current; if the current stands a long time,
the device may damage.
RECOMMENDED OPERATING CONDITIONS
Parameter
IC power supply
MULT input voltage
ZCD current
V1.0
Symbol
VCC
VMULT
IZCD
6
Min.
VCCUV+
0
-2
Typ.
14
-
Max.
22
3.5
2
Unit
V
V
mA
July 2014
PT5634A
ELECTRICAL CHARACTERISTICS
VCC=14V, TA=25°C.
Parameter
Supply Characteristics
VCC supply under voltage positive voltage
threshold
VCC supply under voltage negative voltage
threshold
VCC supply under voltage lockout
hysteresis
VCC UVLO mode quiescent current
In OVP VCC quiescent current
In disable mode VCC quiescent current
VCC operation current (fPFC=50K)
VCC clamp voltage
Error Amplifier Characteristics
Reference voltage in pin INV
Voltage gain
Bandwidth
COMP maximum output voltage
COMP minimum output voltage
COMP maximum sink current
COMP maximum source current
INV Disable threshold
INV Restart threshold
Multiplier Characteristics
MULT input voltage range
Factor of multiplier
OVP Characteristics
OVP threshold
OVP current hysteresis
Static OVP voltage threshold in COMP
Zero Current Detection Characteristics
ZCD positive voltage threshold
ZCD voltage threshold hysteresis
ZCD upper clamp voltage
ZCD lower clamp voltage
ZCD sink current
ZCD source current
Maximum delay from ZCD to GD
Restart timer
Current Sense Characteristics
threshold voltage for current sense
Propagation delay
Leading-edge blanking time
Driver (GD) Characteristics
Turn-on rise time
Turn-off fall time
GD clamp voltage
GD voltage in UVLO mode
V1.0
Symbol
Test Conditions
Min.
Typ.
Max.
VCCUV+
11.5
12.5
13.5
VCCUV-
9
10
11
VUVHYS
-
2.5
-
22
30
0.9
0.9
25
70
1.2
1.2
6
28
2.475
5
2.1
2.0
-2.0
0.1
0.3
2.5
80
1
5.5
2.25
3.5
-3.0
0.2
0.45
2.525
6
2.4
0.3
0.55
V
dB
MHz
0~2.5
0.32
0.38
0.44
V
1/V
IOVP
IHYS
VS_OVP
23.5
2.1
27
20
2.25
30.5
2.4
μA
VZCD
VZCD_HYS
VZCD_HIGH
VZCD_LOW
IZCD_SINK
IZCD_SOURCE
TDEAD
TRESTART
-0.3
2.5
-1.5
100
75
1.4
0.7
6.5
0
190
7.0
0.3
400
300
VCS
TPKD
TLEB
0.98
-
1.08
100
200
1.18
200
400
11
-
50
30
13.5
-
100
70
16
1.1
IQCCUV
IQCCOVP
IQCCSD
ICCOP
VCCCLAMP
VCC=VCCUV+-0.2V
OVP
VZCD<0.2V
GD: 1nF+10R
ICC=10mA
VINV
GV
GB
VCOMP_HIGH
VCOMP_LOW
ICOMP_SINK
VINV=2.4V
VINV=2.6V
VINV=2.6V,VCOMP=4V
VINV=2.4V,VCOMP=4V
ICOMP_SOURCE
VINV_DIS
VINV_EN
VMULT
K
VMULT=1V, VCOMP=4V
IZCD=2.5mA
IZCD=-0.5mA
tr
tf
Vgd_clamp
Vgd_s
GD: 1nF+10R
GD: 1nF+10R
VCC=20V
Igd=10mA
7
Unit
V
μA
mA
V
V
mA
V
V
mA
ns
μs
V
ns
ns
V
July 2014
PT5634A
PT5634A VS PT5634
There are some differences between PT5634A and PT5634, even if they have the same pin-out. The Disable function
has been relocated, and some parameters have been modified.
Parameter
PT5634
PT5634A
VCC supply under voltage positive/negative voltage threshold
Factor of multiplier
Threshold voltage for current sense
OVP threshold
ZCD positive/negative/ lower clamp voltage threshold
Enable threshold
12/9.3V
0.5
1.7V
40uA
2.1/1.6/0.5V
0.3V (1)
12.5/10V
0.38
1.08V
27uA
1.4/0.7/0V
0.45V (2)
(1) Function located on pin 5 (ZCD)
(2) Function located on pin 1 (INV)
V1.0
8
July 2014
PT5634A
PACKAGE INFORMATION
8 PINS, SOP, 150MIL
Symbol
A
A1
A2
b
c
D
E
E1
e
L

Millimeter
Nom.
1.60
0.15
1.40
4.90
6.00
3.90
1.27 BSC.
0.60
-
Min.
1.35
0.08
1.20
0.33
0.17
4.70
5.80
3.70
0.38
0
Max.
1.77
0.28
1.65
0.51
0.26
5.10
6.20
4.10
1.27
8
Note: All dimensions meet JEDEC Standard MS-012 AA do not include mold flash or protrusions.
V1.0
9
July 2014
PT5634A
IMPORTANT NOTICE
Princeton Technology Corporation (PTC) reserves the right to make corrections, modifications, enhancements,
improvements, and other changes to its products and to discontinue any product without notice at any time.
PTC cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a PTC product. No
circuit patent licenses are implied.
Princeton Technology Corp.
2F, 233-1, Baociao Road,
Sindian Dist., New Taipei City 23145, Taiwan
Tel: 886-2-66296288
Fax: 886-2-29174598
http://www.princeton.com.tw
V1.0
10
July 2014