MP4603
White LED Driver for
Large LCD TV Backlights
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The Future of Analog IC Technology
DESCRIPTION
The MP4603 is an integrated white LED driver.
It uses MPS’s patent-pending technology to
drive the backlights for LCD TVs measuring 60-
inches or larger, for LED string voltages up to
350V. This novel technology can leverage the
LED drive power by regulating only a small
portion of the LED drive voltage—together with
a fixed high-voltage source, a low-voltage LED
driver can drive high voltage LED strings. This
method allows for a super-high power density,
higher efficiency and lower cost due to the low
voltage stress, higher switching frequencies,
and smaller passive components.
The MP4603 is a current-mode–controlled
buck-boost regulator. With a 12V input VINL and
a high voltage source VINH, it can deliver a
regulated voltage (VINH to VINH+68V) to drive a
LED string with up to 100 LEDs. It can drive an
external switch in series with the LED string to
achieve over 1:1000 dimming ratio. Analog
dimming can be applied at the same time to
further improve the dimming ratio. Fault
protections include LED open-string protection,
output short-circuit protection, cycle-by-cycle
peak current limiting, and thermal shutdown.
The MP4603 is available in SOIC16 package.
FEATURES
• Novel Power-Leverage-Control Technology
• Unique Step-Up/Down Operation
• Up to 99.5% Efficiency
• 0.5 Internal Power MOSFET
• Switching Frequency Synchronization
• Over 1:1000 Dimming Ratio
• Separate Analog and PWM Dimming
• ±5% 200mV Reference Voltage
• 10A Shutdown Mode
• Cycle-by-Cycle Over-Current Protection
• Thermal Shutdown Protection
• LED String Open and Short Protection
• FAULT Output at LED Protection
• Output Short-Circuit Protection
• Available in SOIC16 Package
APPLICATIONS
• Large LCD Panels Backlighting
• High Power Street LED Lighting
All MPS parts are lead-free and adhere to the RoHS directive. For MPS green
status, please visit MPS website under Products, Quality Assurance page.
“MPS” and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
MP4603 – WHITE LED DRIVER FOR LARGE LCD TV BACKLIGHTS
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TYPICAL APPLICATION
FAULT BST
VIN
INGND
SYN
PWM
EN
ADIM
FST
SW
VSS
DGD
OVP
FB
COMP
SLOPE
Fault
VIN CIN
CLK/SYN
PWM
EN
ADIM
300K
RFAULT
RFST
RSLOPE
300K
CCOMP
10n
100K CBST
100n L1
COUT
R2
R1
RFB
VINH
MP4603
MP4603 – WHITE LED DRIVER FOR LARGE LCD TV BACKLIGHTS
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ORDERING INFORMATION
Part Number Package Top Marking Free Air Temperature (TA)
MP4603ES* SOIC16 MP4603ES -20°C to +85°C
* For Tape & Reel, add suffix –Z (e.g. MP4603ES–Z);
For RoHS Compliant Packaging, add suffix –LF (e.g. MP4603ES–LF–Z)
PACKAGE REFERENCE
ABSOLUTE MAXIMUM RATINGS (1)
VVIN – VSS ........................................-0.3V to 85V
VINGND – VSS.....................................-0.3V to 85V
VSW – VSS ..............................-0.3V to VIN + 0.3V
VBST ...................................................... VSW + 6V
VDGD – VSS .....................................-0.3V to +12V
VVIN – VOCP ......................................-0.3V to +6V
VOVP, VFB, VCOM, VFST – VSS .............-0.3V to +6V
VADIM, VEN, VPWM, VSYN– VINGND.........-0.3V to +6V
Continuous Power Dissipation (TA = +25°C) (2)
SOIC16 ...................................................... 1.6W
Junction Temperature...............................150°C
Lead Temperature ....................................260°C
Storage Temperature............... -65°C to +150°C
Recommended Operating Conditions (3)
Supply Voltage VVIN – VSS ...................5V to 80V
VADIM, VEN, VPWM, VSYN – VINGND..............0V to 5V
Maximum Junction Temp. (TJ) .............. +125°C
Thermal Resistance (4) θJA θJC
SOIC16................................... 80 ...... 30... °C/W
Notes:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ (MAX), the junction-to-
ambient thermal resistance JA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD (MAX) = (TJ
(MAX)-TA)/JA. Exceeding the maximum allowable powe
r
dissipation will cause excessive die temperature, and the
regulator will go into thermal shutdown. Internal thermal
shutdown circuitry protects the device from permanent
damage.
3) The device function is not guaranteed outside of the
recommended operating conditions.
4) Measured on JESD5 1-7, 4-layer PCB.
FAULT
VIN
INGND
SYN
BST
SW
VSS
DGD
1
2
3
4
16
15
14
13
OVP
FB
COMP
SLOPE
12
11
10
9
PWM
EN
ADIM
FST
5
6
7
8
TOP VIEW
PIN 1 ID
SOIC16
MP4603 – WHITE LED DRIVER FOR LARGE LCD TV BACKLIGHTS
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ELECTRICAL CHARACTERISTICS
VVIN = 12V, PWM and AD Pins floating, RFST=51kΩ, TA = +25°C, VVSS=VINGND=0V, unless otherwise
noted.
Parameters Symbol Condition Min Typ Max Units
FB Feedback Voltage VFB 190 200 210 mV
FB Input Current IFB V
FB = 0.2V -0.1 0.1 A
VIN UVLO Rising VVINTH 3.6 4 4.3 V
VIN UVLO Hysteresis VVINHYS 400 mV
Shut Down Current Ioff VEN=0V 10 A
Supply Current (Quiescent) IQ VPWM = 0V,
VFB = 250mV 1.05 1.2 mA
Switch-On Resistance (5) R
DS(ON) 0.5
Switch Leakage ISWLK
VVIN=80V, VEN=0V,
VPWM=0V, VSW=0V 1 A
Switch Current Limit (5) IS_MAX 2.5 A
FST pin open 0.65 0.9 1.2 MHz
Oscillator Frequency fSW RFST = 200k 180 280 390 kHz
FST Output Voltage VFST 1 1.1 1.2 V
VFB = VOVP = 0V, FST pin
open 160
Fold-back Frequency fSWFB VFB = VOVP = 0V, RFST =
200k 40
kHz
SLOPE pin open 0.3 0.5 0.7
Slope Compensation SSLOPE RSLOPE = 200k 0.12 0.17 0.235 V/s
SLOPE Pin Output Voltage VSLOPE 1 1.1 1.2 V
Maximum Duty Cycle DMAX VFB = 0.15V,FST pin open 88 %
Minimum ON-Time (5) tON 270 ns
VSYN = 3.3V 400
SYN Input Current ISYN VSYN = 0V -750 A
Frequency Synchronization Range (5) fSW_SYN 0.1 2 MHz
PWM Dimming OFF Threshold VPWML VPWM Falling 1.65 V
PWM Dimming ON Threshold VPWMH V
PWM Rising 2.2 V
PWM Dimming Frequency 100 50k Hz
Minimum Analog Dimming Threshold VADMIN VFB = 5mV 0 mV
Maximum Analog Dimming Threshold VADMAX V
FB = 200mV 1.2 V
VADIM= 3.3V 36
ADIM Input Current VADIM= 0V -3.5 A
EN OFF Threshold VENL VEN Falling 0.9 V
EN ON Threshold VENH VEN Rising 1.5 V
EN Input Current IEN VEN = 3.3V 3.8 A
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ELECTRICAL CHARACTERISTICS (continued)
VVIN = 12V, PWM and AD Pins floating, RFST=51kΩ, TA = +25°C, VVSS=VINGND=0V, unless otherwise
noted.
Parameters Symbol Condition Min Typ Max Units
Dim Gate Driver Sourcing Current IDGD+ VDGD–VSS= 0V,
VPWM=3V -25 mA
Dim Gate Driver Sinking Current IDGD- VDGD–VSS=10V,
VPWM=1.5V 45 mA
LED Open OV Threshold VOVPTH 1.2 V
LED Short Threshold for Immediate
Latch-Off VFBS 600 mV
LED Short Delay for Latch-Off D_FBS 300mV < VFBS < 600mV 450 s
Thermal Shutdown (5) 150 °C
Thermal Shutdown Hysteresis (5) 20 °C
Note:
5) Guaranteed by design.
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TYPICAL CHARACTERISTICS
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TYPICAL PERFORMANCE CHARACTERISTICS
Performance waveforms are tested on the evaluation board of the Design Example section.
VIN = 12V, VINH = 125V, VLED=180V ILED = 120mA, TA = 25°C, unless otherwise noted.
PWM Dimming Curve Analog Dimming Curve
V
SW
50V/div.
V
IN
10V/div.
V
SS
50V/div.
I
L
500mA/div.
V
SW
50V/div.
V
IN
10V/div.
V
SS
50V/div.
I
LED
100mA/div.
V
SW
50V/div.
V
FAULT
5V/div.
V
SS
50V/div.
I
L
500mA/div.
V
SW
50V/div.
V
FAULT
5V/div.
V
SS
50V/div.
I
SHORT
5A/div.
V
SW
50V/div.
V
EN
5V/div.
V
SS
50V/div.
I
LED
100mA/div.
V
SW
50V/div.
V
PWM
5V/div.
V
SS
50V/div.
I
LED
100mA/div.
Steady State
VIN Start EN Start PWM Dimming
f
PWM
=200Hz, D
PWM
=50%
Open LED Load @ Working Short LED- to GND @
Working
0
20
40
60
80
100
120
140
0 20 40 60 80 100
LED CURRENT (mA)
LED CURRENT (mA)
V
ADIM_EVB
(V)
0
20
40
60
80
100
120
140
0 0.2 0.4 0.6 0.8 1 1.2
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PIN FUNCTIONS
Pin #
SOIC16 Name Description
1 FAULT
Fault Condition Output. Open drain with reference to INGND. FAULT is high-Z during
normal operation, and pulled to INGND when LED short protection or LED open protection
trigger.
2 VIN
Positive Voltage Input. Requires a decoupling capacitor to prevent large input-voltage
spikes.
3 INGND Input Ground Reference.
4 SYN
Frequency Synchronization Input. The switching frequency can be synchronized with an
external clock. Multiple ICs’ frequencies can also be synchronized without the external
clock by connecting all the SYN pins together. They follow the highest set frequency.
5 PWM
PWM Dimming Input. Apply a 100Hz to 50kHz square wave signal with amplitude greater
than 2.2V. The PWM pin voltage is high if left floating.
6 EN Enable Input Pin. A voltage greater than 1.5V will turn on the chip.
7 ADIM
Analog Dimming Input. A voltage in range of 0V to 1.2V on ADIM pin adjusts the LED
current from 0 to 100%. The ADIM pin voltage is high (about 3.3V) if left floating.
8 FST
Frequency Set. A resistor from FST to VSS sets the switching frequency if there is no SYN
input. If left open, switching frequency reverts to an internal default value.
9 SLOPE
Programmable Slope Compensation. Connect a resistor from SLOPE to VSS to set the
slope-compensation peak amplitude. If left open, slope compensation reverts to an internal
default value.
10 COMP
Error Amplifier Output. Connect a capacitor 1nF from the COMP pin to VSS to improve
the stability and to provide a soft-start on start-up or for PWM dimming.
11 FB
LED Current Feedback. The MP4603 regulates the voltage across the current sensing
resistor between FB and VSS with 200mV. If the FB voltage exceeds 300mV for 450µs or
exceeds 600mV, LED short protection triggers.
12 OVP
Over Voltage Protection. Use one external resistor voltage divider from the output to VSS
to program the OVP threshold. This voltage references VSS. When the OVP pin voltage
reaches the 1.2V threshold, the switch turns off and the IC latches off. When the OVP pin
voltage falls below 0.4V and the FB pin voltage is less than 0.1V, the chip frequency folds
back. Program the OVP pin voltage from 0.4V to 1.2V for normal operation.
13 DGD LED Dimming-Switch Gate Drive Output.
14 VSS
Negative Voltage Output. The voltage reference for OVP, FB, COMP, SLOPE, DGD and
FST.
15 SW
Switch Output. The source of the internal MOSFET switch. Connect to the power inductor
and cathode of the Schottky rectifier.
16 BST
Bootstrap. Connect a capacitor between the SW and BST pins to form a floating supply
across the power switch driver.
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BLOCK DIAGRAM
EN
DDIM
INGND
VSS
V0P20
FB
VIN
20X
SYN
INGND
FST
SLOPE
VSS
DRVIN
HSG
BST
SW
OVP
VSS
DGD
COMP
Bandgap
&
Bias
EN
VBG
V0P20
Level
Shift
VSS
VBG
BST
SW
BST
Regulator
OV OVP
Over-
Voltage
Protection
VSS
EA
REF
FB
Soft-
Start
Current
Limit
DIMIN
PWM
ILIM
COMP
Control
Loop
OSC
VBG
INGND
SYN
FST
SCST
SC
CLK
ENI
EN
DDIM
INGND
VSS
VIN
FBREF
DIMIN
Dimming
Control
V0P20
VBG VBG
Diming FET
Gate Drive
DIMIN
FAULT
INGND
PWM
ILIM
CLK
HSON
OV
Logic
FALTDRV
ADIM ADIM
Figure 1: Functional Block Diagram
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OPERATION
The MP4603 is a current mode regulator. The
sensing resistor senses the LED current and the
signal goes an error amplifier, which regulates it
to 200mV through an internal compensation
network—The COMP pin is the output of the
error amplifier. The inductor peak current is
proportional to the COMP voltage. Increasing the
COMP voltage increases the current delivered to
the output.
LED Open Protection
If the LED is open, there is no voltage on the FB
pin. The duty cycle increases until VOVP-VVSS
reaches the shutdown threshold. The top switch
turns off, and the IC latches off. At LED open
protection, the Fault pin goes low.
LED Short Protection
If the FB voltage exceeds 600mV, the IC
immediately latches off and DGD goes low. If the
FB voltage exceeds 300mV for around 450µs, IC
latches off and DGD goes low. The EN pin must
reset to restart the IC. The Fault pin goes low
when the IC latches off.
Dimming Control
The MP4603 allows for both Analog and PWM
dimming. The analog dimming voltage range on
ADIM goes from 0V to1.2V to change the LED
current from 0% to 100% of the maximum LED
current. If the voltage on the ADIM pin exceeds
1.2V or is floating, LED current goes to its
maximum.
PWM dimming uses a square-wave signal with a
100Hz-to-50kHz frequency range and an
amplitude over 2.2V applied to the PWM pin.
PWM dimming can achieve over 1:1000 dimming
ratio with PWM frequency less than 200Hz
During the PWM dimming OFF interval, an
internal switch disconnects the COMP pin
capacitor from the output of the error amplifier:
This holds the COMP voltage during the PWM
OFF interval and increases the LED current
response speed to achieve a high dimming ratio.
Combine PWM and analog dimming to increase
the dimming ratio. Apply a 100Hz to 50kHz PWM
signal on PWM pin and a analog dimming signal
in range of 0V to 1.2V on ADIM pin.
.
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APPLICATION INFORMATION
The MP4603 is a buck-boost LED driver. Its
novel power leverage control technology
provides a highly efficient, low-cost solution for
LCD TV LED drivers. It has a high bus voltage
and a low supply voltage (typically 12V or 24V,
up to 60V) to drive LED backlight strings of
>350V for LCD TVs measuring 60-inch or more.
Setting the LED Current
An external resistor (RFB) sets the maximum LED
current as per:
FB
LED
0.200V
RI
=
Setting the Switching Frequency
An external resistor RFST can set the switching
frequency (fS) as per:
=⋅
S
FST
60k
f0.95MHz
R
This equation applies to a programmable
frequency range between 200kHz and 2MHz.
If FST pin is floating or RFST exceeds 400kΩ, the
switching frequency is set to default value of
0.9MHz.
Setting the Slope Compensation
The MP4603 employs peak-current–mode
control, which needs slope compensation to
avoid sub-harmonic oscillation when the duty
cycle exceeds 50%.
The current loop has effective sense resistance
of 0.4. Given a desired input/output voltage
relationship, estimate the sense current ramp-
down slope as:
L
DOWN
V
S0.4V/s
L
=⋅ μ
Where VL is the voltage across the inductor in
volt; and L is the inductor value in H.
Ensuring current loop stability requires a
compensation slope of at least half of the ramp-
down slope:
SC DOWN
1
SS
2
>=
An external resistor (RSLOPE) can set the slope
compensation for the current loop as per:
SC
SLOPE
60k
V
S=0.6 *
sR
μ
The equation is effective only for a resistor range
from 20k to 400k for RSLOPE.
If SLOPE pin is floating or RSLOPE exceeds 400kΩ,
the slope compensation is set to default value of
0.5V/s.
Selecting the Inductor
The input voltage, output voltage, and LED
current factor into inductor selection. In addition,
select the inductor so that the circuit always
operates in continuous current mode (CCM).
Estimate the inductor value using the following
equation:
IN OUT
SIN OUT L
VV
Lf(V V ) I
⋅
=
⋅
+⋅Δ
Where ΔIL is the inductor peak-to-peak current
ripple. Design ΔIL somewhere around 40% to
60% of the inductor average current, which is:
OUT
L _ AVG LED
IN
V
II(1)
V
=⋅+ .
Select an inductor that does not saturate at the
maximum peak current, which is:
L_PK L_AVG L
II 0.5I
=
+⋅Δ
.
Selecting the Input Capacitor
The input capacitor reduces the surge current
drawn from the input supply and the switching
noise from the device. Use ceramic capacitors
with X5R or X7R dielectrics because they have
low ESR values and small temperature
coefficients. Select a sufficiently-large
capacitance to limit the input voltage ripple (ΔVIN),
which is normally less than 5%-10% of the DC
value.
L_AVG OUT
IN
sININOUT
IV
CfV(VV)
⋅
>⋅Δ ⋅ +
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Selecting the Output Capacitor
The output capacitor normally limits the output
voltage ripple (ΔVOUT) to less than 1%-to-5% of
the DC value, and ensures a stable feedback
loop. Select an output capacitor value with low
impedance at the switching frequency. Use
ceramic capacitors with X5R or X7R dielectrics
for their low ESR characteristics.
LED OUT
OUT
sOUTINOUT
IV
CfV (VV)
⋅
>⋅Δ ⋅ +
Setting the Over Voltage Protection
The output voltages of some converters, such as
buck-boost and boost converters, can rise to very
high levels without a limiting function. Over-
voltage protection (OVP) limits the output voltage
to below the operating rating. Use a voltage
divider to set the OVP point.
=⋅+
1
OVP
2
R
V1.2V(1)
R
Where R1 and R2 are the voltage divider (refer
the TYPICAL APPLICATION). For most
applications, set the OVP point around 10% to
30% higher than the output voltage. Check that
the set OVP point will not exceed the operation
rating.
FAULT Condition Output
The MP4603 has an open drain output as a
FAULT indicator. Under normal conditions,
FAULT is a high-Z output and can be set to any
desired voltage with external resistors. However,
if VFB exceeds VSS by 600mV, or VFB exceeds
VSS by 300mV for ~450s, or OVP triggers at
1.2V, FAULT drops to the INGND level. The Rdson
for this pull down switch is ~100.
PC Board Layout
Place the high-current paths (VSS, VIN and SW)
very close to the device with short, direct, and
wide traces. Place the input capacitor as close as
possible to the VIN and VSS pins. Place the
external feedback resistors next to the FB pin.
Keep the switch node traces short and far away
from the feedback network.
Pay attention to the layout of the high frequency
switching loop, which should be placed as small
as possible.
For buck applications, the high frequency
switching loop is composed of the input capacitor,
the internal switch of IC (VIN pin to SW pin) and
the diode. Place the input capacitor and the
diode close to the IC.
For buck-boost applications, the high frequency
switching loop is composed of the input capacitor,
the internal switch, the diode and the output
capacitor. Place the input and output capacitors
close together, close to the IC, and to the diode.
Top Layer
Bottom Layer
Figure 2: PCB Layout
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TYPICAL APPLICATION CIRCUITS
FAULT BST
VIN
INGND
SYN
PWM
EN
ADIM
FST
SW
VSS
DGD
OVP
FB
COMP
SLOPE
Fault
VIN CIN
CLK/
SYN
PWM
EN
ADIM
300K
RFAULT
RFST RSLOPE
300K
CCOMP
10n
100K CBST
100n L1
COUT
R2
R1
RFB
MP4603
VIN
12V
VINH
150V
LED+
VLED
180V
Fault
VIN
CLK/
SYN
PWM
EN
ADIM
LED-
12V
12V
Block1
Block2 LED-
Figure 3: White LED Driver for TV Applications
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Design Example
This design example shows an LCD TV LED
backlight application. Figure 4 shows the system
power structure block diagram. MPS’s HFC0100
flyback controller controls the flyback, offering 2
outputs: 12VIN and VINH. The high output, VINH,
provides a bias voltage (less
than the LED string voltage) for all LED strings
and connects to the anodes. The low output,
12VIN, is about 12V and supplies the MP4603
LED driver; the MP4603 generates a negative
voltage and connects to the cathode of the LED
strings to drive the LED strings.
HFC0100
Flyback
AC Input
12VIN
VINH
MP4603
LED Driver MP4603
LED Driver
INGND INGND
LED1- LED2-
Figure 4: System Power Block Diagram
Specifications
Flyback Output:
VINH = typical 145V (140V to 160V): cross-
regulation in the multiple output flyback is the
primary cause of the large tolerance.
12VIN is 12V;
Output:
2 outputs of 120mA for every string
LED voltage is typical 180V (165V to 195V)
Switching frequency:
~200kHz
Protections:
Open LED string protection
Short LED string protection
MP4603 Operating Range:
Input voltage = 12V
Output voltage = -5V to -55V
LED current = 120mA.
Figure 5 shows the schematic of the MP4603
LED driver stage. JP1 is short and JP2 is open.
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Figure 5: LED Driver Schematic Used for Evaluation (EV4603-S-00A)
Setting Current Sense Resistor
The sense resistor RFB is:
FB
LED
0.200V
RI
=
Use two 3.32 resistor in parallel (R15 and R16)
as the LED current sensor resistor.
Setting the Frequency Set Resistor
The following equation determines the
frequency set resistor, R18:
S
0.95MHz 60k
R18 f
⋅
=
Select 300k to set the switching frequency to
about 200kHz.
Selecting the Inductor
Select an inductor such that the circuit always
operates in CCM as per the following equation:
⋅
=
⋅+ ⋅⋅+
IN_min OUT_max
OUT_max
S IN_min OUT_max LED
IN_min
VV
L1 V
f(V V )I(1 )
V
Where η is about 40% to 60%. Select an
inductance of 100H and the inductor peak-to-
peak current of 0.49A.
Select an inductor that does not saturate at the
maximum peak current, which is:
L_PK L_AVG L
II 0.5I
=
+⋅Δ
Select L1=100H with a saturation current of
1.5A
Setting the Slope Compensation
The voltage across the inductor in the buck-
boost converter is the output voltage. The
maximum slope compensation is:
=
⋅μ
OUT_max
DOWN
V
S0.4V/s
L
To ensure current-loop stability, select a
compensation slope that is at least half of the
needed ramp-down slope:
SC DOWN
1
SS
2
>=
SSC0.11V/s. Use the slope compensation
resistor RSLOPE to set the slope compensation
for the current loop as per the following
equation:
SC
V
0.6 s
R19 60kS
μ
=⋅
Based on this equation, the slope
compensation resistor cannot exceed 330k.
MP4603 – WHITE LED DRIVER FOR LARGE SIZE BACKLIGHTING
MP4603 Rev1.01 www.MonolithicPower.com 16
7/16/2015 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2015 MPS. All Rights Reserved.MP4603
Select R19=300k as the compensation
resistor.
Selecting the Input and Output Capacitor
Estimate the input capacitor and output
capacitor using the following equations.
L_AVG OUT
IN
sININOUT
IV
CfV(VV)
⋅
>⋅Δ ⋅ +
LED OUT
OUT
sOUTINOUT
IV
CfV (VV)
⋅
>⋅Δ ⋅ +
Where VIN is about 5%-to-10% of the input
voltage, and Vout is about 1%-to-5% of the
output voltage. Select C2=2.2F ceramic
capacitor as the input capacitor and C8=2.2F
as the output capacitor
Setting the Over Voltage Protection
Set the OVP point is about 1.1x-to-1.2x of the
output voltage so that the OVP point is about
60V to 66V.
=⋅+
5
OVP
12
R
V1.2V(1 )
R
Select R12=20k and R5=1M; the OVP point
is 63V.
MP4603 – WHITE LED DRIVER FOR LARGE SIZE BACKLIGHTING
NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications.
Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS
products into any application. MPS will not assume any legal responsibility for any said applications.
MP4603 Rev. 1.01 www.MonolithicPower.com 17
7/16/2015 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2015 MPS. All Rights Reserved.MP4603
PACKAGE INFORMATION
SOIC16
0.016(0.41)
0.050(1.27)
0
o
-8
o
DETAIL "A"
0.010(0.25)
0.020(0.50) x 45
o
SEE DETAIL "A"
0.0075(0.19)
0.0098(0.25)
0.150
(3.80)
0.157
(4.00)
PIN 1 ID
0.050(1.27)
BSC
0.013(0.33)
0.020(0.51)
SEATING PLANE
0.004(0.10)
0.010(0.25)
0.386( 9.80)
0.394(10.00)
0.053(1.35)
0.069(1.75)
TOP VIEW
FRONT VIEW
0.228
(5.80)
0.244
(6.20)
SIDE VIEW
18
16 9
RECOMMENDED LAND PATTERN
0.213
(5.40)
0.063
(1.60)
0.050(1.27)0.024(0.61)
NOTE:
1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN
BRACKET IS IN MILLIMETERS.
2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH,
PROTRUSIONS OR GATE BURRS.
3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH
OR PROTRUSIONS.
4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING)
SHALL BE 0.004" INCHES MAX.
5) DRAWING CONFORMS TO JEDEC MS-012, VARIATION AC.
6) DRAWING IS NOT TO SCALE.
0.010(0.25) BSC
GAUGE PLANE
