MP4601
White LED Driver For
Large Size TV Backlighting
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The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP4601 is an integrated white LED driver.
It can be applied with MPS patent pending
technology to drive up to 60 inch or larger size
LCD TV backlighting, in which the LED string
voltage can be up to 350V. The novel
technology can leverage the LED drive power
by regulating only small portion of the LED drive
voltage. As a result, working together with a
fixed high voltage source, a low voltage LED
driver can be used to drive the high voltage
LED strings with super high power density, high
efficiency and low cost due to the low voltage
stress, high switching frequency, and smaller
size of passive components.
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APPLICATIONS
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TV Backlighting
Large LCD Panels Backlighting
For MPS green status, please visit MPS website under Quality Assurance.
“MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic
Power Systems, Inc.
R
MP4601 is a current mode controlled buckboost regulator. With a 12V input VINL and a
high voltage source VINH, it can deliver a
regulated voltage (VINH to VINH+63V) to drive a
LED string with up to 100 LEDs. It can drive an
external switch, which is in series with the LED
string, to achieve over 1:1000 dimming ratio.
Analog dimming can be applied in the same
time to further improve the dimming ratio. Fault
protection includes LED open strings protection,
output short circuit protection, cycle-by-cycle
peak current limiting, and thermal shutdown.
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Novel Power Leverage Control Technology
Unique Step-up/down Operation
Up to 99.5% Efficiency
0.5Ω Internal Power MOSFET Switch
Switching Frequency Synchronization
Over 1:1000 Dimming Ratio
Analog and PWM Dimming
±5% 200mV Reference Voltage
850µA Quiescent Current
10µA Shutdown Mode
Programmable Cycle-by-Cycle Over Current
Protection
Thermal Shutdown Protection
LED String Open and Short Protection
FAULT Output for Short LED Protection
Output Short Circuit Protection
Available in TSSOP16-EP and SOIC16
Packages
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MP4601 is available in TSSOP16-EP and
SOIC16 packages.
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
1
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
TYPICAL APPLICATION
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120V
R3
100k
VIN
12V
FAULT
VIN
C1
10
BST
MP4601
SW
INGND
VSS
CLK/SYN
SYN
DGD
DIM
DIM
OVP
EN
EN
R1
800k
C OUT
2.2
R2
12k
FB
FST
RFB
2
COMP
SLOPE
RFST
60k
L1
22
CBST
100nF
OCP
RSC
60k
ROCP
100k
CCOMP
100pF
VOUT
Efficiency vs.
External Bus Voltage
R
VINL=12V, VLED=240V, ILED=100mA,
External bus voltage, VINH=180~236V
EFFICIENCY (%)
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100
99
98
97
96
95
94
93
92
91
90
180 190
200 210 220 230 240
EXTERNAL VOLTAGE (V)
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
2
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
ORDERING INFORMATION
Package
Top Marking
MP4601EF*
TSSOP16-EP
MP4601EF
MP4601ES
SOIC16
MP4601ES
Free Air Temperature (TA)
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Part Number
-20°C to +85°C
* For Tape & Reel, add suffix –Z (e.g. MP4601EF–Z);
For RoHS Compliant Packaging, add suffix –LF (e.g. MP4601EF–LF–Z)
PACKAGE REFERENCE
TOP VIEW
PIN 1 ID
VIN
1
16
BST
FAULT
2
15
SW
FAULT
1
16
BST
INGND
3
14
VSS
VIN
2
15
SW
SYN
4
13
DGD
INGND
3
14
VSS
DIM
5
12
OVP
SYN
4
13
DGD
EN
6
11
FB
DIM
5
12
OVP
FST
7
10
COMP
SLOPE
8
9
OCP
EXPOSED PAD
FOR TSSOP20F ONLY
TSSOP16-EP
EN
6
11
FB
FST
7
10
COMP
SLOPE
8
9
OCP
SOIC16
Thermal Resistance
VVIN – VSS ........................................ -0.3V to 85V
VINGND – VSS ..................................... -0.3V to 85V
VSW – VSS ............................ -0.3V to VVIN + 0.3V
VBST ...................................................... VSW + 6V
VDGD – VSS .....................................-0.3V to +12V
VSLOPE, VOCP – VSS ...........................-0.3V to +6V
VOVP, VFB, VCOM, VFST – VSS .............-0.3V to +6V
VFAULT, VDIM, VSYN, VEN – VINGND .......-0.3V to +6V
Continuous Power Dissipation (TA = +25°C) (2)
TSSOP16-EP ............................................. 2.7W
SOIC16 ...................................................... 1.6W
Junction Temperature ...............................150°C
Lead Temperature ....................................260°C
Storage Temperature ............... -65°C to +150°C
TSSOP16-EP ......................... 45 ...... 10... °C/W
SOIC16 .................................. 80 ...... 30... °C/W
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ABSOLUTE MAXIMUM RATINGS (1)
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TOP VIEW
Recommended Operating Conditions
(4)
θJA
θJC
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-toambient thermal resistance θJA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD (MAX) = (TJ
(MAX)-TA)/θJA. Exceeding the maximum allowable power
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.
(3)
Supply Voltage VVIN – VSS ................ 4.5V to 75V
VDIM, VEN, VSYN – VINGND ......................... 0V to 5V
Operating Junct. Temp (TJ)...... -40°C to +125°C
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
3
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
ELECTRICAL CHARACTERISTICS
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VVIN = 12V, PWM and AD Pins floating, RFST=51kΩ, TA = +25°C, VVSS=VINGND=0V, unless otherwise
noted.
Parameters
FB Feedback Voltage
FB Input Current
VIN UVLO Rising
VIN UVLO Hysteresis
Shut Down Current
Supply Current (Quiescent)
Switch-On Resistance
Switch Leakage
Switch Current Limit
IS_MAX
OCP Output Voltage
VOCP
Oscillator Frequency
fSW
FST Output Voltage
VFST
Fold-back Frequency
fSWFB
Slope Compensation
SSLOPE
SLOPE Pin Output Voltage
VSLOPE
Maximum Duty Cycle
R
Minimum On-Time
SYN Input Current
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Frequency Synchronization Range (5)
PWM Dimming OFF Threshold
PWM Dimming ON Threshold
N
Symbol Condition
VFB
IFB
VFB = 0.2V
VVINTH
VVINHYS
Ioff
VEN=0V
VPWM = 0V,
IQ
VFB = 250mV
RDS(ON)
VVIN=80V, VEN=0V,
ISWLK
VPWM=0V, VSW=0V
DMAX
ISYN
fSW SYN
VDIML
VDIMH
IDGD+
Dim Gate Driver Sinking Current
IDGD-
VFB = 5mV
VFB = 200mV
VEN Falling
VEN Rising
VEN = 3.3V
VDGD-VSS=10V,
VDIM=0V
VDGD-VSS=0V
VDIM=2V
1000
µA
Ω
2.5
1.1
0.8
200
1
1.2
0.95
280
1.1
µA
A
1.3
1.2
390
1.2
V
MHz
kHz
V
160
kHz
36
1
0.3
1
VFB = 0.15V,FST
pin open
VSYN = 3.3V
VSYN = 0V
RFST>620kΩ
VDIM Falling
VDIM Rising
VDIM = 3.3V
VDIM = 0V
Units
mV
µA
V
mV
µA
10
1.2
0.39
1.1
1.4
0.47
1.2
V/µs
V
95
%
100
400
-700
ns
0.1
0.6
µA
2
1.7
36
-3.5
100
VADMIN
VADMAX
VENL
VENH
IEN
Dim Gate Driver Sourcing Current
MP4601 Rev. 1.0
1/28/2011
VFB = VOVP = 0V,
FST pin open
VFB = VOVP = 0V,
RFST = 200kΩ
SLOPE pin open
RSLOPE = 200kΩ
3.5
70
10
Max
210
0.1
4.1
0.5
OCP pin open
FST pin open
RFST = 200kΩ
Typ
200
850
tON
DIM Input Current
PWM Dimming Frequency
Minimum Analog Dimming Threshold
Maximum Analog Dimming Threshold
EN OFF Threshold
EN ON Threshold
EN Input Current
Min
190
-0.1
2.7
MHz
V
V
µA
50k
3.8
Hz
V
V
V
V
µA
-25
mA
45
mA
0.7
1.5
0.6
1.7
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MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
4
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
ELECTRICAL CHARACTERISTICS (continued)
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VVIN = 12V, PWM and AD Pins floating, RFST=51kΩ, TA = +25°C, VVSS=VINGND=0V, unless otherwise
noted.
Parameters
LED Open OV Threshold
LED Open OV Hysteresis
LED Short Threshold for Immediate Latch-off
LED Short Delay for Latch-off
Thermal Shutdown
Thermal Shutdown Hysteresis
Symbol Condition
VOVPTH
VOVPHYS
VFBS
300mV < VFBS <
TD_FBS
600mV
Min
Typ
1.2
0.1
600
Max
Units
V
V
mV
480
µs
150
20
°C
°C
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Note:
5) Guaranteed by design.
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
5
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
PIN FUNCTIONS
2
1
3
4
5
6
7
Name
1
VIN
2
FAULT
3
INGND
4
SYN
5
DIM
6
EN
7
FST
8
SLOPE
R
8
Pin #
TSSOP
16-EP
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Pin #
SOIC16
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9
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11
12
MP4601 Rev. 1.0
1/28/2011
9
OCP
10
COMP
11
FB
12
OVP
Description
Positive Voltage Input Pin. A decoupling cap is needed to prevent large voltage
spikes from appearing at the input.
Fault condition output, open drain with reference to INGND. FAULT is high-Z
during normal operation, and pulled to INGND when short LED protection is
triggered.
Input Ground Reference. This pin is the reference for the EN/DIM signal.
Frequency Synchronization Input Pin. The switching frequency can be
synchronized with an external clock, which frequency is higher than the set
frequency with FST resistor. Multiple ICs’ frequencies can also be synchronized
without the external clock by connecting all SYN pins together. They follow the
highest set frequency.
PWM Dimming and Analog Dimming Input Pin.
For digital dimming, apply a 100Hz to 50kHz square wave signal with amplitude
greater than 1.5V to DIM pin.
For analog dimming, apply a voltage between 0.7V and 1.5V to DIM pin. When
DIM voltage changes from 0.7V to 1.5V, the internal reference for FB regulation
changes from 0 to 200mV. A voltage higher than 1.5V at this pin doesn’t modify
the internal reference anymore.
For combined PWM and analog dimming to get a further high dimming ratio,
apply a 100Hz to 50kHz square wave signal with amplitude from 0.7V to 1.5V to
DIM pin.
DIM pin voltage is high (about 3.3V) if it is floating.
Enable Input Pin. A voltage greater than 0.6V will turn on the chip.
Frequency Setting Pin. A resistor from FST to VSS setting the switching
frequency if there is no SYN input. If left open, switching frequency will be set to
internal default value.
Programmable Slope Compensation pin. Connect a resistor from SLOPE pin to
VSS sets slope compensation peak amplitude. If left open, slope compensation
will be set internal default value.
Over Current Protection Pin. Connect a resistor ROCP from OCP pin to VSS sets
the cycle-by-cycle current limit of the inside power FET. If left open, the current
limit is the default value of 2.5A.
Output of error amplifier. Connect a 1nF or larger capacitor on COMP pin to VSS
to improve the stability and to provide a soft on at start up or PWM dimming.
LED Current Feedback Input. MP4601 regulates the voltage across the current
sensing resistor between FB and VSS with 200mV. If FB voltage is higher than
300mV for 480us or FB voltage is higher than 600mV, it triggers the LED short
protection.
Over Voltage Protection Pin. Use one external resistor voltage divider across
INGND and VSS to program OVP threshold. Its voltage is referred to VSS.
When the OVP pin voltage reaches 1.2V threshold, the switch is turned off and
will recover when OVP voltage decreases below 1.1V. When the OVP pin
voltage is lower than 0.4V and FB pin voltage is lower than 0.1V, the chip
frequency will be folded back. Program the OVP pin voltage from 0.4V to 1.2V
for normal operation.
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
6
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
PIN FUNCTIONS (continued)
13
14
15
Name
Description
13
DGD
14
VSS
15
SW
16
BST
LED Dimming Switch Gate Drive Output Pin.
Negative Voltage Output Pin. This pin is the voltage reference for OVP, FB,
COMP, SC, DGD and FST pins. This node should be placed away from
switching noise sources.
Switch Output. SW is the source of the internal MOSFET switch. Connect to the
power inductor and cathode of the Schottky rectifier.
Bootstrap. A capacitor is connected between SW and BST pins to form a floating
supply across the power switch driver.
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16
Pin #
TSSOP
16-EP
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Pin #
SOIC16
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
7
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
TYPICAL PERFORMANCE CHARACTERISTICS
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VIN=12V, VOUT=20V, ILED=200mA, fPWM=200Hz, OVP point=25V, TA=+25°C, unless otherwise
noted.
Efficiency vs. VIN
1
EFFICIENCY (%)
0 .8
0 .6
0 .4
0 .2
0
PWM Dimming Curve
Analog Dimming Curve
200
180
200
180
160
160
140
140
120
120
100
100
80
80
60
60
40
40
20
20
0
15
25
35
VIN (V)
45
55
0
0.2
0.4
0.6
0.8
PWM DIMMING DUTY
1
0
0.6
0.8
1
1.2 1.4 1.6
ANALOG DIMMING VOLTAGE (V)
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5
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
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© 2011 MPS. All Rights Reserved.
8
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
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VIN=12V, VOUT=20V, ILED=200mA, fPWM=200Hz, OVP point=25V, TA=+25°C, unless otherwise
noted.
Steady State
VSW
20V/div.
VOUT
20V/div.
ILED
200mA/div.
IL
500mA/div.
PWM Dimming
VSW
20V/div.
VEN
2V/div.
ILED
200mA/div.
VEN
2V/div.
ILED
200mA/div.
IL
1A/div.
ILED
200mA/div.
IL
1A/div.
2ms/div.
1ms/div.
OVP
Short LED+ to LED(short recover)
VSW
20V/div.
VSW
20V/div.
VOUT
20V/div.
VOUT
20V/div.
ILED
100mA/div.
ILED
100mA/div.
IL
1A/div.
IL
500mA/div.
2ms/div.
1ms/div.
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IL
1A/div.
VSW
20V/div.
VPWM
5V/div.
EN OFF
VSW
20V/div.
EN ON
VSW
10V/div.
Short LED+ to VSS
VIN
10V/div.
ISHORT
2A/div.
IL
1A/div.
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
9
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
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BLOCK DIAGRAM
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Figure 1—Functional Block Diagram
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
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© 2011 MPS. All Rights Reserved.
10
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
OPERATION
Dimming Control
The MP4601 allows both Analog and PWM
dimming. For analog dimming, when the
voltage on DIM is from 0.7V to1.5V, the LED
current will change from 0% to 100% of the
maximum LED current. If the voltage on DIM
pin is higher than 1.5V or DIM pin is floated,
maximum LED current will be generated.
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The MP4601 is a current mode regulator. The
sensing resistor senses the LED current and
feeds it back to an error amplifier, which
regulates it to 200mV with an inside
compensation network. The COMP pin is the
output of the error amplifier. The inductor peak
current is proportional to the COMP pin voltage.
An increase of 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 will increase until VOVPVVSS reaches the shutdown threshold. The top
switch will turn off until the voltage VOVP-VVSS
decreases sufficiently. System enjoys autorecovery for the LED open protection.
LED Short Protection
If the FB voltage is higher than 600mV,
immediately IC is latched off and DGD is pulled
low. If FB voltage is higher than 300mV for
480µs, IC is also latched off and DGD is pulled
low. The EN needs reset to restart the IC. The
Fault pin is pulled low when IC is latched off.
For PWM dimming, a PWM signal with 100Hz
to 50kHz frequency, amplitude over 1.5V
should be applied to DIM pin.
For combined PWM and analog dimming to get
a further high dimming ratio, apply a 100Hz to
50kHz PWM signal with its amplitude from 0.7V
to 1.5V to DIM pin.
DIM pin floated will deliver the maximum LED
current.
At PWM dimming off interval, an internal switch
disconnects the COMP pin capacitor from the
output of the error amplifier. Therefore, the
COMP voltage is hold at PWM off interval. This
feature improves the response speed of the
LED current and helps to achieve high dimming
ratio.
N
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Digital dimming can achieve over 1:1000
dimming ratio with DIM frequency less than
200Hz.
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
11
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
APPLICATION INFORMATION
Setting the LED Current
An external resistor RFB is used to set the
maximum LED current through the use of the
equation:
RFB
0.200V
=
ILED
Setting the Switching Frequency
An external resistor RFST can be used to set the
switching frequency fS through the use of the
equation:
fS = 0.95MHz ⋅
60k
RFST
The equation is effective only for 200kHz to
2MHz frequency programming range.
If FST pin is floating or RFST is larger than
500kΩ, the setting frequency is the default
value 0.95MHz.
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Setting the Current Limit
An external resistor ROCP can be used to set the
cycle-to-cycle current limit ILIM through the use
of the equation:
ILIM = 4.1A ⋅
100k
− 1.1A
ROCP
The equation is effective only for a range from
30k to 500k for the programming resistor ROCP.
O
N
VL
⋅ 0.4 V/µs
L
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MP4601 is a Buck-boost mode LED driver. Its
novel power leverage control technology
provides a high efficiency, low cost solution for
TV LED driver. With a high bus voltage VINH and
a low supply voltage VINL (typical 12V or 24V,
not recommend higher than 60V), MP4601 can
drive over 60 inch or larger size panel for over
350V LED string voltage.
relationship, one can estimate the sense
current ramp down slope as:
If OCP pin is floating or ROCP is larger than
500kΩ, the current limit is the default value of
2.5A.
Setting the Slope Compensation
MP4601 employs peak current mode control,
which will need slope compensation to avoid
sub-harmonic oscillation when duty cycle
exceeds 50%.
SDOWN =
Where VL is the voltage across the inductor,
and L is the inductor value.
To
ensure
current
loop
stability,
a
compensation slope of at least half of the ramp
down slope is needed:
SSC >=
1
SDOWN
2
An external resistor RSLOPE can be used to set
the slope compensation for the current loop
through the use of the equation:
SSC = 1.2 V
60k
⋅
µs R
SLOPE
The equation is effective only for a range from
20k to 500k for the programming resistor
RSLOPE.
If SLOPE pin is floating or RSLOPE is larger than
500kΩ, the slope compensation is set to default
value of 1.2V/µs.
FAULT condition output
MP4601 has an open drain output to indicate
FAULT condition. During normal operation,
FAULT is high-Z output and user can pull it up
to any desired voltage with an external resistor.
However, if for some reason, FB is greater than
600mV above VSS, or FB is greater than
300mV above VSS for a pre-determined time of
~480µs, FAULT will be pulled low to INGND
level. The Rdson for this pull down switch is
~100Ω.
Selecting the Inductor
Inductor selection is related to the input voltage,
output voltage, and LED current. Select the
inductor to make the circuit always operate in
continuous current mode (CCM). The
inductance is designed as:
L=
VIN ⋅ VOUT
fS ⋅ (VIN + VOUT ) ⋅ ∆IL
The current loop has effective sense resistor of
0.4Ω. Given a desired input, output voltage
MP4601 Rev. 1.0
1/28/2011
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© 2011 MPS. All Rights Reserved.
12
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
PC Board Layout
The high current paths (VSS, VDD and SW)
should be placed very close to the device with
short, direct and wide traces. The input
capacitor needs to be as close as possible to
the VDD and VSS pins. The external feedback
resistors should be placed next to the FB pin.
Keep the switch node traces short and away
from the feedback network.
EC
R NE O
EF W M
ER D ME
E
N
TO SI D
ED
G
M N
P4 S FO
60
R
3
Where ∆IL is the inductor peak-to-peak current
ripple. Design ∆IL as about 40% to 60% of the
inductor average current, which is:
IL _ AVG = ILED ⋅ (1 +
VOUT
).
VIN
Make sure the inductor is not saturated at the
maximum peak current, which is:
IL _ PK = IL _ AVG + 0.5 ⋅ ∆IL .
Selecting the Input Capacitor
The input capacitor reduces the surge current
drawn from the input supply and the switching
noise from the device. Ceramic capacitors with
X5R
or
X7R
dielectrics
are
highly
recommended because of their low ESR and
small
temperature
coefficients.
Enough
capacitance is required for limited input voltage
ripple ∆VIN, which should be normally less than
5~10% of the DC value.
CIN >
IL _ AVG ⋅ VOUT
fs ⋅ ∆VIN ⋅ (VIN + VOUT )
Selecting the Output Capacitor
R
The output capacitor keeps the output voltage
ripple ∆VOUT small (normally less than 1~5% of
the DC value) and ensures feedback loop
stable. The output capacitor impedance should
be low at the switching frequency. Ceramic
capacitors with X5R or X7R dielectrics are
recommended for their low ESR characteristics.
N
O
T
COUT >
MP4601 Rev. 1.0
1/28/2011
ILED ⋅ VOUT
fs ⋅ ∆VOUT ⋅ (VIN + VOUT )
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© 2011 MPS. All Rights Reserved.
13
MP4601 – WHITE LED DRIVER FOR LARGE SIZE BACKLIGHTING
EC
R NE O
EF W M
ER D ME
E
N
TO SI D
ED
G
M N
P4 S FO
60
R
3
TYPICAL APPLICATION CIRCUITS
VIN
FAULT
INGND
VSS
SYN
OVP
DIM
DGD
EN
RSC
60K
SW
BST
FB
FST
COM
SLOPE
OCP
ROCP
100K
N
O
T
R
Figure 2—White LED Driver Application for TV Applications
MP4601 Rev. 1.0
1/28/2011
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© 2011 MPS. All Rights Reserved.
14
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
PACKAGE INFORMATION
EC
R NE O
EF W M
ER D ME
E
N
TO SI D
ED
G
M N
P4 S FO
60
R
3
TSSOP16-EP
3.30
TYP
0.40
TYP
4.90
5.10
16
9
1.60
TYP
4.30
4.50
PIN 1 ID
1
0.65
BSC
2.80
TYP
6.20
6.60
5.80
TYP
8
TOP VIEW
RECOMMENDED LAND PATTERN
0.80
1.05
1.20 MAX
SEATING PLANE
0.19
0.30
0.65 BSC
0.00
0.15
0.09
0.20
SEE DETAIL "A"
SIDE VIEW
FRONT VIEW
R
GAUGE PLANE
0.25 BSC
N
O
T
0o-8o
MP4601 Rev. 1.0
1/28/2011
0.45
0.75
DETAIL
A
NOTE:
1) ALL DIMENSIONS ARE IN MILLIMETERS.
2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH,
PROTRUSION OR GATE BURR.
3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH
OR PROTRUSION.
4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING)
SHALL BE 0.10 MILLIMETERS MAX.
5) DRAWING CONFORMS TO JEDEC MO-153, VARIATION ABT.
6) DRAWING IS NOT TO SCALE.
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15
MP4601 – WHITE LED DRIVER FOR LARGE SIZE TV BACKLIGHTING
SOIC16
EC
R NE O
EF W M
ER D ME
E
N
TO SI D
ED
G
M N
P4 S FO
60
R
3
0.386( 9.80)
0.394(10.00)
9
16
PIN 1 ID
0.024(0.61)
0.050(1.27)
0.063
(1.60)
0.150
(3.80)
0.157
(4.00)
0.228
(5.80)
0.244
(6.20)
0.213
(5.40)
8
1
TOP VIEW
RECOMMENDED LAND PATTERN
0.053(1.35)
0.069(1.75)
SEATING PLANE
0.050(1.27)
BSC
0.013(0.33)
0.020(0.51)
0.004(0.10)
0.010(0.25)
SEE DETAIL "A"
SIDE VIEW
FRONT VIEW
0.010(0.25)
x 45o
0.020(0.50)
N
O
T
R
GAUGE PLANE
0.010(0.25) BSC
0o-8o
0.016(0.41)
0.050(1.27)
0.0075(0.19)
0.0098(0.25)
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.
DETAIL "A"
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.
MP4601 Rev. 1.0
1/28/2011
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2011 MPS. All Rights Reserved.
16
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