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February 22, 2012
IRS2500S
TRANSITION MODE PFC CONTROL IC
Features
PFC Control IC
Boost or Flyback Converter Modes
Critical-conduction / Transition mode
operation
Over-current protection
Static and Dynamic DC bus overvoltage
protection
Micropower startup (<50μA)
Low quiescent current (2.5mA)
Latch immunity and ESD protection
Wide range PFC for universal AC line input
Low THD
Open load Over voltage protection
Noise immunity
Typical Applications
Switched Mode Power Supplies
Electronic Ballasts
LED Drivers
Product Summary
Topology Boost / Flyback
Io+ & I o- (typical) 500 / 500 mA
tr & tf (typical) 60 / 30 nS
Packages
8-Lead SOIC
Typical Connection Diagram
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Table of Contents Page
Description 3
Qualification Information 5
Absolute Maximum Ratings 6
Recommended Operating Conditions 6
Electrical Characteristics 7
Functional Block Diagram 9
Input/Output Pin Equivalent Circuit Diagram 10
Lead Definitions 11
Lead Assignments 11
Application Information and Additional Details 12
Package Details 19
Tape and Reel Details 20
Part Marking Information 21
Ordering Information 22
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Description
The IRS2500 is a fully integrated, fully protected PFC SMPS control IC designed to drive Boost or Flyback
switching regulators providing high power factor. Typical applications are PFC pre-regulators for SMPS and
electronic ballasts for fluorescent or HID lighting as well as single stage Flyback converters widely used in
low power LED drivers. The IRS2500 is pin compatible with most industry standard critical conduction or
transition mode PFC control IC with additional improvements to increase performance. The PFC circuitry
provides high PF, low THD and stable DC bus regulation over a wide line/load range. The IRS2500
protection features include cycle by cycle over-current protection and output over voltage protection.
IRS2500S
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Typical Application Diagram
DBUS
T1
BR1
CIN
MPFC
RPFC
RV1
RV2
CVOUT
ROC
IRS2500
1
2
3
4
8
7
6
5
INV
COMP
VDC
OC ZX
COM
OUT
VCC
CF
RF
CVCC
DVCC
RS
IC3A
IC1
RI
RPU
IC2
DIN
RIN
RDC
VREG
CVREG
IC3B
RD1
RD2
RD3
RVFB CVFB
RIFB CIFB
+5V
RZX
OUT+
OUT-
AC
Line
Input
CF
RPD
CCOMP
RFB1
RFB2
RII
RSH
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Qualification Information
Qualification Level
Industrial
††
Comments: This family of ICs has passed JEDEC’s Industrial
qualification. IR’s Consumer qualification level is granted by
extension of the higher Industrial level.
Moisture Sensitivity Level MSL2
†††
260°C
(per IPC/JEDEC J-STD-020)
ESD
Machine Model Class B
(per JEDEC standard JESD22-A115)
Human Body Model Class 2
(per EIA/JEDEC standard EIA/JESD22-A114)
IC Latch-Up Test Class I, Level
A
(per JESD78)
RoHS Compliant Yes
Qualification standards can be found at International Rectifier’s web site http://www.irf.com/
†† Higher qualification ratings may be available should the user have such requirements. Please contact
your International Rectifier sales representative for further information.
††† Higher MSL ratings may be available for the specific package types listed here. Please contact your
International Rectifier sales representative for further information.
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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 COM, all currents are defined positive into any lead.
The thermal resistance and power dissipation ratings are measured under board mounted and still air
conditions.
S
y
mbol Definition Min. Max. Unit
s
VCC Supply Voltage -0.3 VCLAMP
VOUT Gate Driver Output Voltage -0.3 VCC + 0.3 V
IOMAX Maximum allowable output current (OUT) due to external
power transistor miller effect -500 500 mA
ICC VCC current 0 25 mA
VCOMP COMP Pin Voltage
-0.3 VCC + 0.3
V
VOC OC Pin Voltage
VVBUS VBUS Pin Voltage
-0.3 7.0
VDC VDC Pin Voltage
VZX ZX Pin Voltage
ICOMP COMP Pin Current
-5 5 mA
IZX ZX Pin Current
IOC OC Pin Current
PD Package Power Dissipation @ TA +25ºC --- 0.625 W
RθJA Thermal Resistance, Junction to Ambient --- 128
ºC/W
TJ Junction Temperature -55 150
ºC
TS Storage Temperature -55 150
TL Lead Temperature (soldering, 10 seconds) --- 300
Recommended Operating Conditions
For proper operation the device should be used within recommended conditions.
S
y
mbol Definition Min. Max. Units
VCC Supply Voltage V
CCUV+ VCLAMP V
ICC V
CC Supply Current 0 10
mA
IOC OC Pin Current
-1 1
IZX ZX Pin Current
TJ Junction Temperature -25 125 ºC
: This IC contains a zener clamp structure between the chip VCC and COM which has a nominal breakdown voltage of 20V. This
supply pin should not be driven by a DC, low impedance power source greater than the VCLAMP specified in the Electrical
Characteristics section.
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Electrical Characteristics
VCC = 14 V +/- 0.25 V, COUT=1000 pF, CVCC=0.1 μF, TA=25 °C unless otherwise specified.
Symbol Definition Min Typ Max Units Test Conditions
Supply Characteristics
VCCUV+ VCC Supply Undervoltage Positive Going
Threshold 11.5 12.5 13.5
VCCUV- VCC Supply Undervoltage Negative Going
Threshold 9.5 10.5 11.5
VUVHYS VCC Supply Undervoltage Lockout
H
y
steresis 1.5 2.0 3.0
IQCCUV UVLO Mode VCC Quiescent Current --- 30 --- uA VCC = 8V
ICC V
CC Supply Current --- 2.3 5.0 mA
VBUS=2.5V
PFC off time =
5us
VCLAMP V
CC Zener Clamp Voltage --- 20.0 --- V ICC = 10mA
Error Amplifier Characteristics
ICOMP
SOURCE
COMP Pin Error Amplifier Output Current
Sourcin
g
--- 10 ---
mA
VVBUS = 2.4V
VCOMP=4.0V
ICOMP
SINK
COMP Pin Error Amplifier Output Current
Sinkin
g
--- -23 --- VVBUS = 2.6V
VCOMP=4.0V
VCOMPOH Error Amplifier Output Voltage Swing (high
state
--- 6.0 ---
V
VBUS=2.0V
ICOMP=-0.5m
A
VCOMPOL Error Amplifier Output Voltage Swing (low
state
--- 0.25 --- VBUS=3.0V
ICOMP=+0.5m
A
VCOMPFL
T
Error Amplifier Output Voltage in Fault
Mode --- 0 --- VBUS=3.0V
IVBUS Input bias current --- --- -1 uA VBUS=0 to 3V
Gv Voltage gain 60 80 --- dB Open loop
GB Bandwidth --- 1 --- MHz
Control Characteristics
VVBUS VBUS Internal Reference Voltage 2.46 2.5 2.54
V
VCOMP = 4.0V
VZX+ ZX Pin Threshold Voltage (Arm) --- 1.6 ---
VZX- ZX Pin Threshold Voltage (Trigger) --- 0.7 ---
VZXclamp ZX pin Clamp Voltage (high state) --- 5.2 --- IZX = 1mA
VDCclamp VDC pin Clamp Voltage --- 5.2 --- IDC = 1mA
tBLANK OC pin current-sensing blank time --- 320 --- ns VBUS=2.5V
VCOMP=4.0V
tWD PFC Watch-dog Pulse Interval --- 400 --- us ZX = 0,VCOMP =
4.0V
tONMIN PFC Minimum ON time --- 0.3 --- us ZX = 0,VCOMP =
0.25V
tONMAX PFC Maximum ON Time 10 50 --- us
ZX = 0,VCOMP =
6.0V,
VDC = 2V
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Electrical Characteristics (cont’d)
VCC = 14V +/- 0.25V, COUT = 1000pF,
VCOMP = VOC = VBUS = VZX = 0V, TA=25C unless otherwise specified.
Protection Circuitry Characteristics
VOCTH OC Pin Over-current Sense Threshold 0.93 1.1 1.22 V
VVBUSOV VBUS Over-voltage Comparator
Threshold 2.7
Guaranteed by
desi
g
n
VVBUSOV
HYS
VBUS Over-voltage Comparator
H
y
steresis 50 100 150 mV
Guaranteed by
desi
g
n
ICOMPOV+ Dynamic Over-voltage detection
threshold 30 uA
ICOMPOV- Dynamic Over-voltage detection reset 8
Gate Driver Output Characteristics
VOL Low-Level Output Voltage --- 0
100 mV IO = 0
VOH High-Level Output Voltage --- 0 11 V IO = 0
tr Turn-On Rise Time --- 60
110 ns
tf Turn-Off Fall Time --- 30 70
I0+ Source Current --- 500 --- mA
I0- Sink Current --- 500 ---
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Functional Block Diagram
OUT
COMP
ZX
VZXCLAMP
VZX
QS
R2 Q
R1
Q
S
RQ
VCC
OC VCC COM
VBUS
8
4
1
7
2
5
Watchdog
Timer
6
OVP
VVBUSOV
VVBUS
VCLAMP
VOCTH
Blank Time
VDC 3ON TIME
MODULATOR
UVLO
VDCCLAMP
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Input/Output Pin Equivalent Circuit Diagrams
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Lead Definitions
Symbol Description
VBUS DC Bus Sensing Input
COMP PFC Error Amplifier Compensation
VDC Full Wave Voltage Input
OC PFC Current Sensing Input
ZX PFC Zero-Crossing Detection
COM IC Power & Signal Ground
OUT Gate Drive Output
VCC Logic & Low-Side Gate Driver Supply
Lead Assignments
7
6
5
IRS2500
COM
1
2
3
VBUS
4
COMP OUT
ZX
VCC
8
OC
VDC
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Application Information and Additional
Details
Power factor correction is required in many
electrical appliances in order to minimize reactive
current losses in AC power transmission lines. The
degree to which an electronic circuit matches an
ideal purely resistive load is measured by the phase
shift (displacement) between the input voltage and
input current and the amount of current waveform
distortion. In other words how well the shape of the
input current waveform matches the shape of the
sinusoidal input voltage.
The power factor (PF) is defined as the ratio
between real power and apparent power with the
maximum value of 1.0 representing a totally
resistive load where the current waveform shape
matches the voltage waveform shape exactly. The
distortion of the input current waveform is quantified
by the total harmonic distortion (THD), which is the
sum of all harmonic content of the waveform
expressed as a percentage.
An ideal power factor of 1.0 corresponds to zero
phase shift and a THD of 0% representing a purely
sinusoidal input current waveform in phase with the
line voltage. The lower the power factor the more
current is needed to supply the same power to the
load, which results is higher conduction losses in
transmission lines. For this reason it is desirable to
have a high PF and a low THD. To achieve this, the
IRS2500 implements an active power factor
correction (PFC) circuit.
The control method implemented in the IRS2500
may be used in a Boost converter (Figure 8) or a
low power single stage Flyback converter for small
power supplies or LED drivers. The IRS2500
operates in critical-conduction mode (CrCM), also
known as transition mode. This means that during
each switching cycle of the PFC MOSFET, the
circuit waits until the inductor current discharges to
zero before turning the PFC MOSFET on again.
The PFC MOSFET is turned on and off at a much
higher frequency (>10KHz) than the line input
frequency (50 to 60Hz).
CBUS
+
(+)
(-)
MPFC
LPFC DPFC
DC Bus
Figure 8: Boost converter circuit.
When the switch MPFC is turned on, the inductor
LPFC is connected between the rectified line input
(+) and (-) causing the current in LPFC to increase
linearly. When MPFC is turned off, LPFC is
connected between the rectified line input (+) and
the DC bus capacitor CBUS through diode DPFC.
The stored energy in LPFC is transferred to the
output, supplying a current into CBUS. MPFC is
turned on and off at a high frequency and the
voltage on CBUS charges up to a specified voltage.
The voltage feedback loop of the IRS2500
regulates the output to the desired voltage by
continuously monitoring the DC output and
adjusting the on-time of MPFC accordingly. If the
output voltage is too high, the on-time is decreased
and if it is too low, the on-time is increased. This
negative feedback control loop operates with a slow
loop speed and a low loop gain such that the
average inductor current smoothly follows the low-
frequency line input voltage to obtain high power
factor and low THD.
The loop speed is intentionally slow with respect to
the AC line frequency so that there is no
appreciable change in the on time during a single
line half cycle. This allows the current to follow
shape of the sinusoidal voltage.
V, I
t
Figure 9: Sinusoidal line input voltage (solid line),
triangular PFC Inductor current and smoothed
sinusoidal line input current (dashed line) over one
half-cycle of the AC line input voltage.
Corrections to the output voltage therefore require
several line cycles. With a fixed on-time, and an off-
time determined by the inductor current discharging
to zero, the result is a system where the switching
frequency is free-running and constantly changing
from a high frequency near the zero crossing of the
AC input line voltage, to a lower frequency at the
peaks (Figure 9).
When the line input voltage is low (near the zero
crossing), the inductor current will increase only a
small amount and the discharge time will be short
resulting in a high switching frequency. When the
input line voltage is high (near the peak), the
inductor current will charge up to a much higher
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level and the discharge time will be longer giving a
lower switching frequency.
The PFC control circuit of the IRS2500 (Figure
10) includes six control pins: VBUS, COMP, ZX,
OUT, VDC and OC. The VBUS pin measures the
DC bus voltage through an external resistor voltage
divider. The COMP pin voltage determines the on-
time of MPFC and sets the feedback loop response
speed with an external RC integrator. The ZX pin
detects when the inductor current discharges to
zero each switching cycle using a secondary
winding from the PFC inductor. The OUT pin is the
low-side gate driver output for the external
MOSFET, MPFC. The VDC pin senses the line
input cycle providing phase information to control
the on time modulation described in the next
section. The OC pin senses the current flowing
through MPFC and performs cycle-by-cycle over-
current protection.
RVBUS1
RVBUS2
RVBUS
CCOMP
LPFC
MPFC
RPFC
DFPC
CBUS
(+)
(-)
RZX
PFC
Control
VBUS
COMP
OUT
ZX
COM
OC
ROC
RDC
RIN
VDC
Figure 10: IRS2500 simplified PFC control
circuit.
The VBUS pin is compared with a fixed internal
2.5V reference voltage for regulating the DC output
voltage (Figure 11). The feedback loop error
amplifier increases or decreases the COMP pin
voltage. The resulting voltage on the COMP pin
sets the threshold for the charging of the internal
timing capacitor (C1, Figure 11) and therefore
determines the on-time of MPFC.
The error amplifier operates at a slow loop speed
preventing rapid changes in PWM duty cycle during
a single input line cycle. This prevents distortion
achieving high power factor and low THD.
5
2
1
Q
S
RQ
2.0V
VBUS
COMP
ZX
5.1V
2.5V
2.75 7OUT
QS
R2 Q
R1
COMP3
COMP4
COMP5 RS3
RS4
VCC
M1
WATCH
DOG
TIMER
M2
C1
4OC
1.2V
On Time
Modulator
3
VDC
Figure 11: IRS2500 detailed PFC control circuit.
The off-time of MPFC is determined by the time it
takes the LPFC current to discharge to zero. The
zero current level is detected by a secondary
winding on LPFC that is connected to the ZX pin
through an external current limiting resistor RZX. A
positive-going edge exceeding the internal
threshold VZX+ signals the beginning of the off-
time. A negative-going edge on the ZX pin falling
below VZX- will occur when the LPFC current
discharges to zero, which signals the end of the off-
time and MPFC is turned on again (Figure 12). The
ZX pin is internally biased to ensure that the voltage
detected from the inductor drops fully to zero before
triggering the next PWM cycle. A wide hysteresis
prevents false triggering by ringing oscillations.
The cycle repeats itself indefinitely until the
IRS2500 is disabled through an over-voltage
condition on the DC bus or if the negative transition
of ZX pin voltage does not occur. Should the
negative edge on the ZX pin not occur, MPFC will
remain off until the watch-dog timer forces a turn-on
of MPFC for an on-time duration programmed by
the voltage on the COMP pin. The watch-dog
pulses occur every 300-400us (tWD) indefinitely
until a correct positive and negative-going signal is
detected at the ZX pin and normal operation is
resumed. Should the OC pin voltage exceed the
VOCTH over-current threshold during the on-time
the gate drive output will turn off. The circuit will
then wait for a negative-going transition on the ZX
pin or a forced turn-on from the watch-dog timer to
turn the output on again.
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ILPFC
OUT
ZX
OC
VOCTH
. . .
. . .
. . .
. . .
Figure 12: Inductor current, OUT pin, ZX pin and
OC pin timing diagram.
On-time Modulation Circuit
A fixed on-time of MPFC over an entire cycle of the
line input voltage produces a peak inductor current
which naturally follows the sinusoidal shape of the
line input voltage. The smoothed, averaged line
input current is in phase with the line input voltage
for high power factor but a high total harmonic
distortion (THD), as well as individual higher
harmonics, of the current are still possible. This is
mostly due to cross-over distortion of the line
current near the zero-crossings of the line input
voltage. To achieve low harmonics that are
acceptable for compliance with international
standards and general market requirements, an
additional on-time modulation circuit has been
added to the PFC control. This circuit dynamically
increases the on-time of MPFC as the line input
voltage nears the zero-crossings (Figure 13). This
causes the peak LPFC current, and therefore the
smoothed line input current, to increase near the
zero-crossings of the line input voltage. This
reduces the amount of cross-over distortion in the
line input current which reduces the THD and
higher harmonics. The on time modulation function
is controlled via the VDC input. The full wave
rectified voltage from the bridge rectifier is divided
down by RIN and RDC to provide an input with a
peak voltage of approximately 1V at 90VAC input
and 3V at 277VAC. CDC is added to remove noise
from the signal, the value is typically 10nF. The on
time modulation function is not required in some
applications. In such cases the VDC input should
be tied to VCC through a 10K resistor.
0
0
ILPFC
OUT
pin
near peak region of
rectified AC line
near zero-crossing region
of rectified AC line
Figure 13: On-time modulation circuit timing
diagram.
Output Over-voltage Protection
The IRS2500 incorporates both static and dynamic
overvoltage protection. Static over voltage
protection monitors the feedback voltage at the
VBUS pin and disables the gate drive output if this
voltage exceeds the target voltage by 8%. This is
activated by an internal comparator set to detect a
threshold of 2.7V, which is 8% above the regulation
threshold of 2.5V.
However, under startup condition or when a load is
removed from the output the error amplifier output
voltage at the COMP pin swings low. Since the
compensation capacitor CCOMP is connected from
this output back to the VBUS input a current will
flow during the COMP voltage transition. This pulls
down the VBUS voltage, which allows the output
voltage to exceed the desired regulation level
during the transition and results in an overshoot
before the voltage at the VBUS input exceeds the
regulation threshold.
In order to compensate for this effect, the IRS2500
includes dynamic detection of the error amplifier
output current. During a swing in the negative
direction the error amplifier output current peaks at
a much high level than the level during steady state
operation. This higher current is internally detected
and triggers the overvoltage protection circuitry
disabling the PWM output until the error amplifier
output has settled to a new level. This prevents the
output voltage from overshooting the desired level
by a significant amount under the transient
conditions described. For this reason the loop
should be designed such that voltage ripple at
COMP is minimized during steady state operation.
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PCB Layout Guidelines
For correct operation of the IRS2500, the PCB
should be designed to avoid noise coupling to the
control inputs and ground loops. By following the
recommendations listed here potential issues will be
avoided:
1. The circuit signal and power grounds should be
joined together at one point only. The signal ground
should be a star point located close to the COM pin
of the IRS2500.
2. The point at which the signal ground is connected
to the power ground is recommended to be at the
current sense resistor (ROC) ground.
3. A 0.1μF noise decoupling capacitor should be
located between the VCC and COM pins of the
IRS2500 located as close to the IC as possible.
4. All traces to the VBUS input should be as short as
possible. This means that resistors and capacitors
that are connected to this input should be located as
close to the IRS2500 as possible. The voltage
feedback divider resistor connected to COM should
be connected to a signal ground close to the COM
pin.
5. Traces carrying high voltage switching signals
such as those connected to the MOSFET drain or
gate drive signals should not be located close to
traces connected directly to the VBUS input.
6. The divider network resistor (RDC) and filter
capacitor (CDC) connected to the VDC input of the
IRS2500 should be located as closely to the IC as
possible with the grounded end connected to the
circuit signal ground.
7. The compensation capacitor CCOMP should be
located close to the IRS2500 with short traces
leading to the VBUS and COMP pins.
8. The over current detection filter resistor (ROC)
and capacitor (COC) should be located as close to
the IRS2500 as possible with COC connected to the
circuit signal ground.
9. The zero crossing detection resistor should be
located close to the IRS2500 if possible to prevent
possible noise appearing at this input.
Figure 14: Layout Example
Figure 14 shows a layout where the IRS2500 is
located on the bottom side of the PCB. The bottom
side traces are shown in red and the top side traces
in pale blue. The circuit power ground can be seen
at the C2 GND node with the signal ground star
point is located at the junction between RPFC6 and
CPFC4 to the left of the IRS2500 (IC1). (Note that
the component designators in this example are
different from those used in the datasheet
schematics)
The traces from IC1 pin 6, RPFC3 and CPFC1 (the
VDC divider low side) all run directly to the star
point without crossing any other grounds. The
signal ground is connected to the power ground at
the current sense resistor. A large trace can be
seen running from the star point off the left to where
the MOSFET is situated (not shown). This is the
single point where the signal and power grounds
are connected. The VCC supply decoupling
capacitor shown in this example is CPFC4, which is
located very close to the IRS2500 and grounded
directly to the signal ground star point.
Traces leading to pin 1 (VBUS) are all short and
components connected to pin 1 (RPFC5, RPFC6
and RPFC7) are all located close to IC1. There are
no traces connected to high voltage switching
nodes located anywhere close to pin 1.
The board layout shown in figure 14 complies with
all of the guidelines stated enabling optimum
operation of the IRS2500.
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PFC Design Equations (for Boost Converter)
Step1: Calculate PFC inductor value:
VBUSPf VACVACVBUS
L
OUTMIN
MINMIN
PFC
=2)2( 2
η
[Henries] (1)
where,
VBUS = DC bus voltage
MIN
VAC = Minimum rms AC input voltage
η
= PFC efficiency (typically 0.95)
MIN
f = Minimum PFC switching frequency at minimum AC input voltage
OUT
P = Ballast output power
Step 2: Calculate peak PFC inductor current:
η
=
MIN
OUT
PK VAC P
i22 [Amps Peak] (2)
Note: The PFC inductor must not saturate at PK
i over the specified ballast operating temperature range. Proper core sizing
and air-gapping should be considered in the inductor design.
Step 3: Calculate PFC over-current resistor ROC value:
PK
OC i
VOCTH
R= where VOCTH = 1.1V [Ohms] (3)
Step 4: Calculate start-up resistor RVCC value:
IQCCUV
VAC
RPK
MIN
VCC
10+
= [Ohms] (4)
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Graph 1: VCCUV+ vs. Temperature
Graph 3: IQCCUV vs. Temperature
Graph 2: ICC vs. Temperature
Graph 4: VCLAMP vs. Temperature
0
2
4
6
8
10
12
14
25 0 25 50 75 100 125
TEMPC
VCCUV(+/)
VCCUV+
VCCUV
0
0.5
1
1.5
2
2.5
25 0 25 50 75 100 125
TEMPC
ICC(mA)
0
20
40
60
80
100
120
25 0 25 50 75 100 125
TEMPC
IQCCUV(uA)
20
20.2
20.4
20.6
20.8
21
21.2
21.4
21.6
21.8
22
25 0 25 50 75 100 125
TEMPC
VCLAMP(V)
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Graph 5: VBUS reference vs. Temperature
40
41
42
43
44
45
46
47
48
49
50
25 0 25 50 75 100 125
TEMPC
PFCTonmax(US)
Graph 7: PFC Ton max (us)
Graph 6: Watch dog interval vs. Temperature
Package Details
2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3
25 0 25 50 75 100 125
TEMPC
VBUS(V)
0
50
100
150
200
250
300
350
400
450
500
25 0 25 50 75 100 125
TEMPC
WATCHDOGINTERVAL(us)
IRS2500S
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IRS2500S
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Tape and Reel Details
E
F
A
C
D
G
A
BH
N
OTE : CONTROLLING
DIMENSION IN MM
LOADED TAPE FEED DIRECTION
A
H
F
E
G
D
B
C
CARRIER TAPE DIMENSION FOR 8SOICN
Code MinMaxMinMax
A 7.90 8.10 0.311 0.318
B 3.90 4.10 0.153 0.161
C 11.70 12.30 0.46 0.484
D 5.45 5.55 0.214 0.218
E 6.30 6.50 0.248 0.255
F 5.10 5.30 0.200 0.208
G 1.50 n/a 0.059 n/a
H 1.50 1.60 0.059 0.062
Metric Imperial
REEL DIMENSIONS FOR 8SOICN
Code Min Max Min Max
A 329.60 330.25 12.976 13.001
B 20.95 21.45 0.824 0.844
C 12.80 13.20 0.503 0.519
D 1.95 2.45 0.767 0.096
E 98.00 102.00 3.858 4.015
F n/a 18.40 n/a 0.724
G 14.50 17.10 0.570 0.673
H 12.40 14.40 0.488 0.566
Metric Imperial
IRS2500S
www.irf.com © 2012 International Rectifie
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Part Marking Information
IRS2500S
www.irf.com © 2012 International Rectifie
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Ordering Information
Base Part Number Package Type Standard Pack Complete Part Number
Form Quantity
IRS2500 SOIC8 Tube/Bulk 95 IRS2500SPBF
Tape and Reel 2500 IRS2500STRPBF
The information provided in this document is believed to be accurate and reliable. However, International Rectifier assumes no
responsibility for the consequences of the use of this information. International Rectifier assumes no responsibility for any infringement
of patents or of other rights of third parties which may result from the use of this information. No license is granted by implication or
otherwise under any patent or patent rights of International Rectifier. The specifications mentioned in this document are subject to
change without notice. This document supersedes and replaces all information previously supplied.
For technical support, please contact IR’s Technical Assistance Center
http://www.irf.com/technical-info/
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