IRF IRS2530DPBF Dim8tm dimming ballast control ic Datasheet

July 09, 2008
IRS2530D(S)
DIM8
DIMMING BALLAST CONTROL IC
Product Summary
IC Features
•
•
•
•
•
•
•
•
•
•
•
TM
Dimming ballast control plus half-bridge driver
Closed-loop lamp current dimming control
Internal non-ZVS protection
Internal crest factor protection
Programmable preheat time
Fixed dead-time (2.0μs typ.)
Lamp insert auto-restart
Internal bootstrap MOSFET
Internal 15.6V zener clamp diode on Vcc
Micropower startup (250μA)
Latch immunity and ESD protection
Topology
Half-Bridge
VOFFSET
600 V
VOUT
VCC
IO+ & IO- (typical)
180mA & 260mA
Deadtime (typical)
2.0μs
Package Types
Ballast System Features
•
•
•
•
•
•
•
•
•
Single chip dimming solution
Simple lamp current dimming control method
Single lamp current sensing resistor required
No half-bridge current-sensing resistor required
No external protection circuits required (fully
PDIP8
SO8
internal)
Flash-free lamp start at all dimming levels
Large reduction in component count
Typical applications
Easy to use for fast design cycle time
•
Linear dimming ballast (down to 10%)
Increased manufacturability and reliability
•
3-way dimming ballast
•
Multi-level switch dimming ballast
Typical Connection Diagram
L
AC
LINE
INPUT
F1
LF
BR1
RVCC1
N
RVCC2
RLIM1
CF
CBUS
VCC
CVCC2
COM
VB
1
8
IRS2530D
CVCC1
RLIM2
2
CDIM
DIM
CVCO
VCO
3
4
7
6
5
RHO
MHS
HO
VS
LO
LRES:A
CDC
CBS
LRES:B
CSNUB
RLO
CRES
MLS
SPIRAL
CFL LAMP
CH1
DCP2
RDIM1
1-10V
DIM
INPUT
RLMP2
CPH RVCO
(+)
RLMP1
CH2
CFB
RFB
DCP1
LRES:C
RDIM2
(-)
RCS
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© 2008 International Rectifier
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IRS2530D(S)
Table of Contents
Page
Description
3
Qualification Information
4
Absolute Maximum Ratings
5
Recommended Operating Conditions
6
Electrical Characteristics
7
Input/Output Pin Equivalent Circuit Diagram
9
Lead Definitions
10
Lead Assignments
10
State Diagram
11
Application Information and Additional Details
12
Package Details
20
Tape and Reel Details
21
Part Marking Information
22
Ordering Information
23
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© 2008 International Rectifier
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IRS2530D(S)
Description
This IC takes full advantage of IR’s patented ballast and high-voltage technologies to realize a simple, highperformance dimming ballast solution. A single high-voltage pin senses the half-bridge current and voltage
to perform necessary ballast protection functions. The DC dim input voltage reference and the AC lamp
current feedback have been coupled together allowing a single pin to be used for dimming. Combining these
high-voltage control algorithms together with a simple dimming method in a single 8-pin IC results in a large
reduction in component count, an increase in manufacturability and reliability, a reduced design cycle time,
while maintaining high dimming ballast system performance
Block Diagram
Bootstrap
MOSFET
VCC 1
Driver
Logic
UVLO
COM 2
High-Side
Half-bridge
Driver
8
VB
7
HO
6
VS
5
LO
1uA
Voltage
Controlled
Oscillator
VCO 4
Fault
Logic
Crest
Factor
Protection
Non-ZVS
Protection
Dimming
Control
DIM
Half-bridge
Voltage
Sensing
Low-Side
Half-bridge
Driver
3
Restart
Logic
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© 2008 International Rectifier
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IRS2530D(S)
†
Qualification Information
Qualification Level
Moisture Sensitivity Level
Machine Model
ESD
Human Body Model
IC Latch-Up Test
RoHS Compliant
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.
MSL2†††
SOIC8
(per IPC/JEDEC J-STD-020C)
Not applicable
PDIP8
(non-surface mount package style)
Class C
(per JEDEC standard EIA/JESD22-A115)
Class 3A
(per EIA/JEDEC standard JESD22-A114)
Class I, Level A
(per JESD78A)
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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© 2008 International Rectifier
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IRS2530D(S)
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.
Symbol
Definition
Min.
Max.
VB
High-Side Floating Supply Voltage
-0.3
625
VS
High-Side Floating Supply Offset Voltage
VB - 25
VB + 0.3
VHO
High-Side Floating Output Voltage
VS - 0.3
VB + 0.3
VLO
Low-Side Output Voltage
-0.3
VCC + 0.3
VVCO
VCO Input Voltage
-0.3
6
VDIM
DIM Input Voltage
-0.3
VCC + 0.3
††
†
ICC
---
20
-500
500
dVS/dt
Supply Current
Maximum allowable current at LO, HO and PFC due to
external power transistor Miller effect.
Allowable VS Pin Voltage Slew Rate
-50
50
PD
Maximum Power Dissipation @ TA ≤ +25ºC, 8-Pin DIP
---
1.0
PD
Maximum Power Dissipation @ TA ≤ +25ºC, 8-Pin SOIC
---
0.625
RθJA
Thermal Resistance, Junction to Ambient, 8-Pin DIP
---
85
RθJA
Thermal Resistance, Junction to Ambient, 8-Pin SOIC
---
128
TJ
Junction Temperature
-55
150
TS
Storage Temperature
-55
150
TL
Lead Temperature (Soldering, 10 seconds)
---
300
IOMAX
Units
V
mA
V/ns
W
ºC/W
ºC
†
This IC contains a zener clamp structure between the chip VCC and COM which has a nominal
breakdown voltage of 15.6V. This supply pin should not be driven by a DC, low impedance power
source greater than the VCLAMP specified in the Electrical Characteristics section.
††
This IC contains a zener clamp structure between the chip VCO and COM which has a nominal
breakdown voltage of 7.25V. This pin should not be driven by a DC, low impedance power source
greater than the VVCOMAX specified in the Electrical Characteristics section.
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IRS2530D(S)
Recommended Operating Conditions
For proper operation the device should be used within the recommended conditions.
Symbol
VBS
Definition
Min.
Max.
Units
VCC - 0.7
VCLAMP
V
600
V
VCCUV+ + 0.1V
VCLAMP
V
VCC
High-Side Floating Supply Voltage
Steady State High-Side Floating Supply
Offset Voltage
Supply Voltage
ICC
Supply Current
---
5
mA
VVCO
VCO Pin Voltage
0
6
V
TJ
Junction Temperature
-40
125
ºC
VS
†††
-3.0
†††
Care should be taken to avoid output switching conditions where the VS node decreases below
COM by more than 5V.
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IRS2530D(S)
Electrical Characteristics
VCC=VBS=14V, VS=0V, CVCC=CBS=0.1μF, CVCO=CDIM=10nF, CLO=CHO=1nF, and TA = 25°C unless
otherwise specified. The output voltage and current (VO and IO) parameters are referenced to COM and are
applicable to the respective HO and LO output leads.
Symbol
Definition
Min
Typ
Max
Units
Test Conditions
Low Voltage Supply Characteristics
VCLAMP
VCC Zener Clamp Voltage
14.6
15.6
16.6
VCCUV+
Rising VCC UVLO+ Threshold
11.5
12.5
13.5
VCCUV-
Falling VCC UVLO- Threshold
9.5
10.5
11.5
VCC Undervoltage Lockout Hysteresis
1.5
2.0
3.0
IQCCUV
Micropower Startup VCC Supply Current
---
250
---
µA
VCC = 8V
ICCDIM
DIM Mode VCC Supply Current
---
4.5
---
mA
MODE = DIM
IQCCFLT
Fault Mode VCC Supply Current
VCO Pin Zener Clamp Voltage
---
375
---
µA
MODE = FAULT
---
7.25
---
V
MODE = DIM
VBS Supply Current
---
2
3
mA
MODE = DIM
IQBSUV
UVLO Mode VBS Quiescent Current
---
---
50
µA
VBS = 7V
VBSUV+
Rising VBS Supply Undervoltage
Threshold
Falling VBS Supply Undervoltage
Threshold
Offset Supply Leakage Current
8.0
9.0
10.0
7.0
8.0
9.0
---
---
50
VCCUVHY
VVCOMAX
ICC = 10mA
V
Floating Supply Characteristics
IBS
VBSUVILK
V
μA
VB = VS = 600V
Ballast Control Characteristics
fMIN
Minimum Output Frequency
32.0
34.2
36.4
fMAX
Maximum Output Frequency
---
115
---
Duty Cycle
---
50
---
%
Output Deadtime (HO or LO)
---
2.0
---
µs
MODE = ALL
VCO Pin Charging Current
---
1
---
µA
MODE = PH/IGN
VLOSD+
LO Pin Shutdown Threshold
---
8.75
---
VLOSD-
LO Pin Re-start Threshold
---
8.5
---
VZVSTH
VS Non-ZVS Detection Threshold
---
4.5
---
VCO Fault Rising Threshold
---
4.0
---
Crest factor peak-to-average fault factor
---
5.5
---
d
DT
IVCO
VVCOFLT+
CSCF
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kHz
VCO = 6V
VCO = 0V
MODE = FAULT
V
MODE = FAULT
MODE = DIM, LO
= HIGH
V
MODE = PH/IGN
N/A
MODE = DIM
VS offset = 0.5V
© 2008 International Rectifier
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IRS2530D(S)
Electrical Characteristics
VCC=VBS=14V, VS=0V, CVCC=CBS=0.1µF, CVCO=CDIM=10nF, CLO=CHO=1nF, and TA = 25°C unless
otherwise specified. The output voltage and current (VO and IO) parameters are referenced to COM and are
applicable to the respective HO and LO output leads.
Symbol
Definition
Min
Typ
Max
Units
---
0.0
---
V
Test Conditions
Dimming Control Characteristics
VDIMREG
DIM Regulation Threshold
MODE = DIM
Gate Driver Output Characteristics (HO and LO)
VOH
High-Level Output Voltage
---
VCC
---
IO = 0A
VOL
Low-Level Output Voltage
---
COM
---
IO = 0A
---
IO = 0A,
VCC ≤ VCCUV-
VOL_UV
---
UV-Mode Output Voltage
COM
tr
Output Rise Time
---
120
220
tf
Output Fall Time
---
50
80
tSD
Shutdown Propagation Delay
---
350
---
IO+
Output source current
---
180
---
IO-
Output sink current
---
260
---
ns
mA
Bootstrap FET Characteristics
VB_ON
VB when the bootstrap FET is on
---
13.3
---
IB_CAP
VB source current when FET is on
30
55
---
IB_10V
VB source current when FET is on
8
12
---
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V
mA
CBS = 0.1µF
VB = 10V
© 2008 International Rectifier
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IRS2530D(S)
I/O Pin Equivalent Circuit Diagrams
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IRS2530D(S)
Lead Definitions
Pin #
Symbol
Description
1
VCC
Logic and internal gate drive supply voltage
2
COM
IC power and signal ground
3
DIM
Dimming DC reference and AC lamp current feedback input
4
VCO
Voltage-controlled oscillator (VCO) input
5
LO
Half-bridge low-side gate driver output
6
VS
High voltage floating supply return and half-bridge sensing input
7
HO
High-side gate driver output
8
VB
High-side gate driver floating supply
Lead Assignments
1
COM
2
DIM
3
VCO
4
8
IRS2530D
VCC
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VB
7 HO
6 VS
5 LO
© 2008 International Rectifier
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IRS2530D(S)
State Diagram
Power Off
VCC > 0V
UVLO Mode
Half-Bridge Off
VCC < 10.5V (VCCUV-)
or
LO > 8.75V (VLOSD+)
(Lamp Removed)
IQCCUV ≅ 250μA
VCO = 0V
HO Off
LO Open Circuit
VCC > 12.5V (VCCUV+)
and
LO < 8.5V (VLOSD-)
(Lamp Inserted)
VCC < 10.5V (VCCUV-)
FAULT Mode
Fault Latch Set
Half-Bridge Off
IQCCUV ≅ 250μA
HO Off
LO Open Circuit
VCO > 4.0V
(VVCOFLT+)
(Lamp non-strike)
PH/IGN Mode
Half-Bridge Oscillating
Freq ramps from fMAX to fMIN
VCO Charging (1μA)
non-ZVS Disabled
Crest Factor Disabled
Lamp Ignites
CF > 5.5 (lamp removal)
DIM Mode
non-ZVS
ZVS
freq = freq + df
ZVS OK
Half-Bridge Oscillating @fDIM
Dimming Loop Enabled
non-ZVS Enabled
Crest Factor Enabled
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IRS2530D(S)
Application Information and Additional Details
Information regarding the following topics is included as subsections within this section of the datasheet:
•
•
•
•
•
•
•
•
UVLO Mode and IC Supply Circuitry
Preheat/Ignition (PH/IGN) Mode
Dim Mode
Non Zero-Voltage Switching (ZVS) Protection
Crest Factor Over-current Protection
Fault Mode and Lamp Reset
Component Selection
PCB Layout Guidelines
UVLO Mode and IC Supply Circuitry
The Under-Voltage Lock-Out Mode (UVLO) is defined as the state the IC is in when VCC is below the turn-on
threshold of the IC, VCCUV+ (12.5 V, typical), and LO is above the shutdown threshold, VLOSD+ (8.75 V, typical).
The UVLO circuit is designed to maintain an ultra-low supply current IQCCUV (<250 μA), and to guarantee that
the IC is fully functional before the high- and low-side output gate drivers are activated. The VCC capacitor,
CVCC, is charged up from the DC bus voltage through supply resistors RVCC1 and RVCC2 (Figure 1). The
values of these resistors are chosen such that VCC reaches the UVLO+ turn-on threshold voltage at the
desired DC bus voltage level. Once the capacitor voltage on VCC reaches the start-up threshold, VCCUV+, the
IC turns on and the HO and LO gate drive outputs start oscillating. The capacitor CVCC should be large
enough to hold the voltage at VCC above the VCCUV- threshold until the external auxiliary supply can take over
and supply the required voltage and current to the IC.
DCBUS(+)
RVCC1
RVCC2
DCP2
RLIM1
MHS
RLIM2
VCC
1
CVCC1
CVCC2
COM
2
CDIM
15.6V
CLAMP
DIM
3
DIM REF
and FB
VCO
4
VB
Bootstrap
FET
Driver
VCC
UVLO
8
Highand
Lowside
Driver
RHO
TO LOAD
HO
7
VS
CBS
CSNUB
6
LO
RLO
5
CVCO
MLS
CPH RVCO
DCP1
DCBUS(-)
LOAD RETURN
Figure 1, UVLO and supply circuitry.
An external charge pump circuit consisting of capacitor CSNUB and diodes DCP1 and DCP2, comprises the
auxiliary supply voltage for the low-side circuitry (Figure 1). To limit high peak currents that can flow from the
external charge pump to VCC, a zener diode (18 V, typical) should be used for the lower charge pump diode,
DCP1. Also, two low-ohmic resistors (RLIM1 and RLIM2, 10 Ω each, typical) should be used together with
CVCC1 and CVCC2 to further limit and filter fast current spikes to minimize resulting voltage spikes that can
occur at VCC. An internal bootstrap MOSFET between VCC and VB and external supply capacitor, CBS,
determine the supply voltage for the high-side driver circuitry (Figure 1). The bootstrap MOSFET is turned on
when LO is ‘high’ and charges CBS from VCC each cycle to maintain the VB-to-VS voltage above the VBSUVthreshold (8 V, typical). The value of CBS should be chosen such that the VB-to-VS voltage and ripple stays
above VBSUV- at all times. When VCC exceeds VCCUV+ for the first time, LO will first oscillate for several cycles
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IRS2530D(S)
until the VB-to-VS voltage exceeds the high-side UVLO rising threshold, VBSUV+ (9 V, typical), and the highside driver is enabled. The capacitor CVCC should be large enough such that VCC does not reach UVLObefore HO is enabled and the charge pump supply takes over.
External gate drive resistors, RHO and RLO, are also recommended as standard design practice to limit high
peak currents that can flow into or out of the HO and LO gate drive outputs.
During UVLO Mode, the high-side gate driver output, HO, is ‘low’ and the VCO pin is pulled down internally
to COM. The low-side gate driver output, LO, is open circuit and is used as a shutdown/reset input function
for automatically restarting the IC when a lamp has been removed and re-inserted. The IC includes an
internal shutdown threshold, VLOSD+ (8.75 V, typical), and re-start logic circuit at the LO pin that is only
active during UVLO mode. If VCC is above VCCUV+, but the lamp is removed, the external pull-up network
(RLMP1 and RLMP2) will pull LO above VLOSD+ and the IC will remain in UVLO mode. When the lamp is reinserted, the lower filament of the lamp will pull LO down below VLOSD- (8.5 V, typical) and the IC will exit
UVLO Mode and enter Preheat/Ignition Mode.
Preheat/Ignition (PH/IGN) Mode
When VCC exceeds VCCUV+ and the LO pin is below VLOSD-, the IC enters Preheat/Ignition Mode. An internal
current source, IVCO (1 μA, typical), (Figure 2) charges the external capacitor on pin VCO causing the voltage
on pin VCO to start ramping up linearly. An additional quick-start current, IVCOQS (50 μA, typical), is also
connected to the VCO pin and charges the VCO pin initially to 0.85 V. The quick-start current charges the
VCO voltage up quickly to the internal 1 to 5 V range of the internal VCO. When the VCO voltage exceeds
0.85 V the quick-start current is then disconnected internally and the VCO voltage continues to charge up
with the normal frequency sweep current source, IVCO (1 μA, typical) (Figure 3).
DCBUS(+)
RVCC1
RVCC2
DCP2
MHS
RLIM1
RLIM2
VCC
CVCC1
CVCC2
CDIM
COM
2
8
Highand
Lowside
Driver
15.6V
CLAMP
DIM
3
DIM REF
and FB
VB
Bootstrap
FET
Driver
1
1uA
RHO
HO
VS
LO
RLO
5
VCO
CVCO
CPH RVCO
CSNUB
CBS
6
VCO
4
TO LOAD
7
MLS
4.6V
+
_
Fault
Logic
DCP1
DCBUS(-)
LOAD RETURN
Figure 2, Preheat/Ignition Mode circuitry.
The frequency ramps down from the maximum frequency towards the resonance frequency of the high-Q
ballast output stage. The lamp filaments are preheated as the lamp voltage and load current increase. The
voltage on pin VCO continues to increase and the frequency keeps decreasing until the lamp ignites. If the
lamp ignites successfully, the IC will then enter DIM Mode (Figure 3).
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IRS2530D(S)
VVCO
4.0V
VVCOFLT+
0.85V
Preheat/Ignition Mode
Dim Mode
Freq
fmax
fmin
Lamp Ignites
VLAMP
AC lamp current
VDIM
DC dim reference
Figure 3, Preheat/Ignition/Dim Mode timing diagram.
The resonant output stage transitions to a series-L, parallel-RC circuit with the Q-value and operating point
determined by the user dim level (Figure 4). If the lamp does not ignite, the voltage on pin VCO continues to
increase and the frequency continues to decrease until the VCO voltage exceeds VVCOFLT+ (4.0V, typical) and
the IC enters Fault Mode and shuts down. The minimum frequency should be set below the high-Q
resonance frequency of the ballast output stage to ensure that the frequency ramps through resonance for
lamp ignition (Figure 4). The desired preheat time can be set by adjusting the slope of the VCO ramp with
the external capacitor, CPH.
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IRS2530D(S)
High-Q
Vout
Vin
Ignition
10%
ea
eh
Pr
50%
t
Start
100%
Low-Q
fmin f100% f50% f10%
fmax
Frequency
Figure 4, Resonant tank Bode plot with lamp
dimming operating points.
Dim Mode
When the lamp ignites, the ballast output stage becomes a series-L, parallel-RC circuit and the AC lamp
current flows through the current sensing resistor, RCS. The resulting AC voltage across resistor RCS is
coupled to the DIM pin through feedback resistor, RFB (1 kΩ, typical), and feedback capacitor, CFB (0.1 μF,
typical). The DIM pin voltage is a combination of the DC offset voltage provided by the user dim setting and
the AC voltage that is capacitively coupled through capacitor CFB from the lamp current sensing resistor to
the DIM pin. The IC enters Dim Mode when the lamp ignites and the dimming control loop becomes active.
The DC+AC voltage at the DIM pin is regulated by the control loop such that the valley of the AC voltage
always stays at COM. By offsetting the AC voltage with a DC reference and holding the valley of the AC
voltage at COM, the amplitude of the AC voltage, and therefore the AC lamp current, is accurately controlled.
When the DC reference voltage at the DIM pin is decreased for dimming, the valleys of the AC voltage are
pushed below COM. The dimming control circuit increases the frequency to decrease the AC lamp current
until the AC valleys at the DIM pin are at COM again. When the DC reference is increased to increase the
brightness level, the valleys of the AC voltage increase above COM. The dimming control circuit decreases
the frequency to increase the AC lamp current until the AC valleys at the DIM pin are at COM again. In this
way, the dimming control circuit keeps the AC lamp current peak-to-peak amplitude regulated to the desired
value at all DC dim level settings. Capacitor CVCO programs the speed of the dimming loop and is typically
set to a low value (2.2 nF, typical) for cycle-by-cycle lamp current control. An additional compensation
network is formed by RVCO (1.5 kΩ, typical) and CPH to prevent the VCO voltage from changing too much
from one cycle to the next for maintaining smooth and stable dimming. A capacitor, CDIM (10 nF, typical) is
also necessary from the DIM pin to COM for filtering high-frequency switching noise.
During Dim Mode, the VS-sensing circuit and non-ZVS and crest factor protection circuits are also enabled
(see State Diagram, Page 11).
Non Zero-Voltage Switching (ZVS) Protection
During Dim Mode, if the voltage at the VS pin has not slewed entirely to COM during the dead-time such that
there is voltage between the drain and source of the external low-side half-bridge MOSFET when LO turnson, then the system is operating too close to, or, on the capacitive side of resonance. The result is non-ZVS
capacitive-mode switching that causes high peak currents to flow in the half-bridge MOSFETs that can
damage or destroy them (Figure 5). This can typically occur during a decrease of the DC bus during an AC
mains interrupt or brown-out condition, lamp variations over time, driving an incorrect lamp type, or
component and temperature variations. To protect against this, an internal high-voltage MOSFET is turned
on at each turn-off of HO and the VS-sensing circuit measures the VS voltage at each rising edge of LO. If
the VS voltage is greater than VZVSTH (4.5 V, typical), the non-ZVS control circuit will increase the frequency
until ZVS is reached again. Increasing the frequency due to non-ZVS during a brown-out also ensures that
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© 2008 International Rectifier
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IRS2530D(S)
that the ignition/preheat ramp will be reset to re-ignite the lamp reliably in case the DC bus decreases too far
and the lamp extinguishes.
LO
HO
!
VS
I
L
I
I
!
MLS
MHS
!
Too close to resonance.
Hard-switching and high
peak MOSFET currents!
Frequency shifted higher
to maintain ZVS.
Figure 5, Non-ZVS protection timing diagram.
Crest Factor Over-current Protection
The IRS2530D uses the VS-sensing circuitry to also measure the low-side half-bridge MOSFET current for
detecting an over-current fault. By using the RDSon of the external low-side MOSFET for current sensing, the
IC eliminates the need for an external current sensing resistor. To cancel changes in the RDSon value due to
temperature and MOSFET variations, the IC performs a crest factor measurement that detects when the
peak current exceeds the average current by a factor of 5.5 (CSCF). Measuring the crest factor is ideal for
detecting when the inductor saturates due to excessive current that occurs in the resonant tank when the
frequency is too close to resonance. During Dim Mode, the crest factor over-current protection is used to
detect if the filaments fail, the lamp is removed, or the lamp becomes deactivated. During each of these fault
conditions, the output stage will transition to a series-LC configuration. The resonant inductor, LRES, and
resonant capacitor, CRES, remain connected together to form a complete circuit due to the voltage-mode
heating configuration to the lamp (see Typical Application Diagram, Page 1). The frequency will move
towards resonance until the inductor saturates. The crest factor protection circuit will then detect the
saturation and the IC will enter Fault Mode and shut down.
Fault Mode and Lamp Reset
During Fault Mode the internal fault latch is set, HO is off, LO is open circuit, and the IC consumes an ultralow micro-power current (see State Diagram, Page 11). The IC can be reset with a lamp exchange (as
detected by the LO pin) or a recycling of VCC below and back above the UVLO thresholds. During Fault
Mode, the LO pin is open circuit and is used as an input pin for resetting the IC. If the lamp is removed, the
external pull-up network at the lower lamp filament, RLMP1 and RLMP2 (see Typical Application Diagram,
Page 1), will pull LO above VLOSD+ (8.75V, typical) and the IC will exit Fault Mode and enter UVLO mode.
When the lamp is re-inserted, the lower filament of the lamp will pull LO down below VLOSD- (8.5V, typical)
and the IC will exit UVLO Mode and enter Preheat/Ignition Mode and restart the lamp.
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© 2008 International Rectifier
16
IRS2530D(S)
Component Selection
Proper design of the circuit schematic (see Typical Application Diagram, Page 1) and component selection is
important for achieving proper ballast functionality and preventing problems. The following design procedure
should be followed for determining the various programming and filtering component values:
1) Capacitor CPH programs the desired preheat/ignition time. CPH is charged up by an internal 1 μA
current source at the VCO pin. The value of CPH is determined by:
CPH =
IVCO ⋅ t PH / IGN 1μA ⋅ t PH / IGN
=
VVCOFLT
4V
2) Capacitor CVCO programs the speed of the dimming feedback loop. To ensure smooth and stable
dimming, CVCO should be small enough such that the dimming loop reacts to lamp current changes
each switching cycle. The value of CVCO is typically fixed for most lamp types and is given as:
CVCO = 2.2nF
3) Resistor RVCO and capacitor CPH provide additional compensation of the dimming loop to prevent
the VCO voltage from changing too much over a given switching cycle. The value of RVCO is
typically fixed for most lamp types and is given as:
RVCO = 1.5kΩ
4) Resistor RCS measures the lamp current for dimming. RCS should be kept small to minimize power
losses but the peak voltage across RCS at the lowest lamp current dimming level should be above a
minimum level to avoid noise problems. Using the minimum rms lamp current during dimming, a
minimum allowable peak voltage level across RCS of 100 mV, and an additional factor of 5 (signal
attenuation due to RFB and CDIM), the value of RCS is determined by:
RCS =
100mV
I LAMP _ RMS _ MIN ⋅ 2
×5
Using the maximum rms lamp current, the power loss in resistor RCS is then determined by:
PLOSS _ RCS = ( I LAMP _ RMS _ MAX ) 2 × RCS
5) The additional feedback components include RFB for current limiting and noise filtering, CFB for DC
blocking, and CDIM for noise filtering. The value of these components are typically fixed for most
lamp types and are given as:
R FB = 1kΩ
C FB = 0.1μF
C DIM = 10nF
6) Capacitors CVCC2 and CBS are the low-side and high-side supply capacitors for maintaining their
respective supply voltages and providing high-frequency noise filtering. These capacitors are
typically fixed and are given as:
CVCC 2 = C BS = 0.1μF
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© 2008 International Rectifier
17
IRS2530D(S)
Component Selection (continued)
7) Resistors RVCC1 and RVCC2 provide the micro-power supply current to VCC and therefore
determine the AC line input voltage where the ballast first turns on. The value of these resistors is
determined by:
RVCC1 + RVCC 2 =
VAC ON ⋅ 2 − VCCUV +
250uA
8) The additional supply components include capacitor CVCC1 for holding up VCC until the charge
pump takes over, charge pump capacitor CSNUB for providing VCC supply current, charge pump
diodes DCP1 and DCP2, and limiting resistors RLIM1 and RLIM2 for preventing high currents from
flowing into VCC. These components are typically fixed for most design and are given as:
CVCC1 = 1μF
C SNUB = 1nF / 1KV
DCP1 = 18V / 500mW
DCP 2 = 1N 4148
R LIM 1 = RLIM 2 = 10Ω
9) Resistors RLMP1 and RLMP2 provide the necessary pull-up signal to the LO pin for detecting the
removal and insertion of the lower lamp filament. Both of these resistor should be high-ohmic to
minimize current flow from VCC and to minimize current flow from the low-side filament to the LO
pin. These resistor values are typically fixed and are given as:
RLMP1 = 470 KΩ
R LMP 2 = 1MΩ
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© 2008 International Rectifier
18
IRS2530D(S)
PCB Layout Guidelines
Proper care should be taken when laying out a PCB board to minimize noise effects due to high-frequency
switching and to ensure proper functionality of the IRS2530D.
IC and programming
components
CPH
IC COM
connects to
Power GND
at single point
Dim
Input
(+)
(-)
RVCO
CVCO
1
RLIM2
RLO
DCP2
CBS
CFB
RVCC2
CVCC2
CVCC1
RLIM1
VCC charge
pump circuitry
CDIM
Lamp current sensing
and feedback
RHO
RFB
Power Ground
RCS
RLMP2
Lamp Return
Filament Sensing
RLMP1
RVCC1
Adjacent COM trace for
additional noise filtering
of feedback signal.
DCP1
(+) DC Bus
Half-Bridge Output (VS)
CSNUB
MLS
High-side GND (VS)
connects to half-bridge
mid-point at single point
(-) DC Bus
MHS
High-voltage, high-current and
high-frequency half-bridge output
Figure 9, Typical through-hole and SMD single-layer PCB layout for Application Diagram, Page 1
(bottom copper layer shown from top view).
The programming components for the IC should be connected to the IC COM pin and then connected to
power ground at a single point (Figure 9). The lamp current sensing feedback components (RFB, CFB)
should be kept as far away as possible from the high-voltage/high-frequency half-bridge components to
prevent switching noise from distorting the lamp current feedback signal. Adjacent ground traces to the
feedback signals can also help reduce switching noise. In general, the following guidelines should be
followed during PCB board layout:
1) Place all IC supply capacitors (CVCC2, CBS) and as close as possible to their respective supply and
return pins (CVCC, CBS).
2) Place all IC programming and filter components as close as possible between their respective pins
and COM (CVCO, RVCO, CPH, CDIM, CFB, RFB).
3) Connect IC COM to power GND at one connection only. Do not route power GND through the
programming components or IC COM!
4) Connect high-side gate-drive ground (VS) to half-bridge mid-point at one connection only. Do not
route high-side power ground through the VS components or VS pin.
5) Connect the anode of charge pump diode DCP1 to power ground. Do not connect to IC COM.
6) Use gate resistors (RLO, RHO) between all gate driver outputs and the gate of their respective
power MOSFETs.
7) Use zener diode (18 V, typical) for lower charge pump diode (DCP1) and limiting resistors and
capacitors (RLIM1, CVCC1, RLIM2, CVCC2) to filter high current spikes that can cause large voltage
spikes to occur on VCC.
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© 2008 International Rectifier
19
IRS2530D(S)
Package Details
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© 2008 International Rectifier
20
IRS2530D(S)
Tape and Reel Details: SOIC8N
LOADED TAPE FEED DIRECTION
A
B
H
D
F
C
NOTE : CONTROLLING
DIM ENSION IN M M
E
G
CARRIER TAPE DIMENSION FOR
Metric
Code
Min
Max
A
7.90
8.10
B
3.90
4.10
C
11.70
12.30
D
5.45
5.55
E
6.30
6.50
F
5.10
5.30
G
1.50
n/a
H
1.50
1.60
8SOICN
Imperial
Min
Max
0.311
0.318
0.153
0.161
0.46
0.484
0.214
0.218
0.248
0.255
0.200
0.208
0.059
n/a
0.059
0.062
F
D
C
B
A
E
G
H
REEL DIMENSIONS FOR 8SOICN
Metric
Code
Min
Max
A
329.60
330.25
B
20.95
21.45
C
12.80
13.20
D
1.95
2.45
E
98.00
102.00
F
n/a
18.40
G
14.50
17.10
H
12.40
14.40
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Imperial
Min
Max
12.976
13.001
0.824
0.844
0.503
0.519
0.767
0.096
3.858
4.015
n/a
0.724
0.570
0.673
0.488
0.566
© 2008 International Rectifier
21
IRS2530D(S)
Part Marking Information
Part number
IRSxxxxx
Date code
YWW ?
Pin 1
Identifier
?
MARKING CODE
P
Lead Free Released
IR logo
? XXXX
Lot Code
(Prod mode –
4 digit SPN code)
Assembly site code
Per SCOP 200-002
Non-Lead Free Released
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© 2008 International Rectifier
22
IRS2530D(S)
Ordering Information
Standard Pack
Base Part Number
Package Type
PDIP8
IRS2530D
SOIC8N
Complete Part Number
Form
Quantity
Tube/Bulk
50
IRS2530DPBF
Tube/Bulk
95
IRS2530DSPBF
Tape and Reel
2500
IRS2530DSTRPBF
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/
WORLD HEADQUARTERS:
233 Kansas St., El Segundo, California 90245
Tel: (310) 252-7105
www.irf.com
© 2008 International Rectifier
23
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