MP3399EF-LF [MPS]
LED Driver, 12-Segment, PDSO28, TSSOP-28;
| 型号： | MP3399EF-LF |
| 厂家： | 
MONOLITHIC POWER SYSTEMS |
| 描述： | LED Driver, 12-Segment, PDSO28, TSSOP-28 驱动 光电二极管 接口集成电路 |
| 文件： | 总19页 (文件大小：560K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MP3399
12-String, Cascading White LED Driver
For Extending LED Channels
The Future of Analog IC Technology
DESCRIPTION
The MP3399 is a step-up controller with 12-
channel current sources designed for driving
the WLED arrays for large size LCD panel
FEATURES
12 String, 60mA/String WLED Driver
Cascading Capability with a single Power
Source
backlighting applications.
The MP3399 is
5V to 28V Input Voltage Range
Maximum 60mA for Each String
2.5% Current Matching Accuracy Between
Strings
flexible for extending LED channels with two or
more MP3399s in parallel while operating from
a single Inductor power source.
Programmable Switching Frequency
PWM or DC Input Burst PWM Dimming
Open and Short LED Protection
Programmable Over-voltage Protection
Under Voltage Lockout
The MP3399 uses current mode, fixed frequency
architecture. The switching frequency is
programmable by an external frequency setting
resistor. It drives an external MOSFET to boost
up the output voltage from a 5V to 28V input
supply. The MP3399 regulates the current in
each LED string to the programmed value set by
an external current setting resistor.
Thermal Shutdown
28-pin TSSOP and 28-pin SOIC Package
APPLICATIONS
The MP3399 applies 12 internal current
sources for current balance. And the current
matching can achieve 2.5% regulation accuracy
between strings. Its low 600mV regulation
voltage on LED current sources reduces power
loss and improves efficiency.
Desktop LCD Flat Panel Displays
Flat Panel Video Displays
LCD TVs and Monitors
All MPS parts are lead-free and adhere to the RoHS directive. For MPS green
status, please visit MPS website under Quality Assurance. “MPS” and “The
Future of Analog IC Technology” are Registered Trademarks of Monolithic
Power Systems, Inc.
PWM dimming is implemented with external
PWM input signal or DC input signal. The
dimming PWM signal can be generated internally,
and the dimming frequency is programmed by
an external setting capacitor.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
1
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
TYPICAL APPLICATION
VOUT
D1
M1
L1
String
String
String13
1
12
String
24
VIN
CIN
COUT
5V~28V
VFAULT
CFAULT
RF1
2
3
27
26
24
28
25
23
22
21
20
19
18
17
16
15
VIN
VFAULT
GATE
ISENSE
NC
RF2
VCC
M2
VCC
CVCC
COMP
C
COMP
4
COMP
EN
R
SENSE
5
Enable
8
OSC
PGND
OVP
ROSC
1
NC
10
7
BOSC
GND
DBRT
ISET
LED12
LED11
LED10
LED9
LED1
RBOSC
MP3399
LED2
LED3
LED4
LED5
LED6
LED7
LED8
6
DIMMING
R
SET
9
11
12
13
14
2
27
26
24
28
25
23
22
21
20
19
18
17
16
15
VIN
VFAULT
GATE
ISENSE
NC
VCC
CVCC
3
4
VCC
VOUT
COMP
COMP
EN
RF3
RF4
5
8
OSC
PGND
OVP
ROSC
1
NC
10
7
BOSC
GND
DBRT
ISET
LED12
LED11
LED10
LED9
LED1
RBOSC
MP3399
LED2
LED3
LED4
LED5
LED6
LED7
LED8
6
RSET
9
11
12
13
14
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
2
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
ORDERING INFORMATION
Part Number
MP3399EF*
MP3399EY**
Package
TSSOP28
SOIC28
Top Marking
3399EF
Free Air Temperature (TA)
-40C to +125C
3399EY
-40C to +125C
*For Tape & Reel, add suffix –Z (eg. MP3399EF–Z).
For RoHS compliant packaging, add suffix –LF (eg. MP3399EF–LF–Z)
**For Tape & Reel, add suffix –Z (eg. MP3399EY–Z).
For RoHS compliant packaging, add suffix –LF (eg. MP3399EY–LF–Z)
PACKAGE REFERENCE
TOP VIEW
1
28
27
26
25
24
23
22
21
20
19
18
17
16
15
NC
NC
2
VFAULT
GATE
VIN
3
VCC
4
PGND
ISENSE
OVP
COMP
5
EN
6
DBRT
7
LED1
LED2
LED3
LED4
LED5
GND
8
OSC
9
ISET
10
BOSC
11
LED12
12
LED11
LED6
LED7
LED8
13
LED10
14
LED9
TSSOP28
SOIC28
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance (4)
θJA
θJC
VIN .................................................-0.3V to +30V
TSSOP28................................32 ....... 6....C/W
SOIC28 ..................................60 ...... 30...C/W
VGATE ..............................................-0.5V to 6.8V
VVCC................................................-0.5V to 6.8V
VLED1 to VLED12 ..................................-1V to +50V
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 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.
All Other Pins...............................-0.3V to +6.3V
(2)
Continuous Power Dissipation (TA = +25°C)
TSSOP28…………………………………...3.9 W
SOIC28………………………………………2.1W
Junction Temperature...............................150C
Lead Temperature ....................................260C
Storage Temperature............... -65C to +150C
3) The device is not guaranteed to function outside of its
operation conditions.
4) Measured on JESD51-7, 4-layer PCB.
Recommended Operating Conditions (3)
Supply Voltage VIN ..............................5V to 28V
LED Current (Backlight) .............10mA to 60mA
Operating Junction Temp.(TJ).... -40C ~+125C
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
3
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
ELECTRICAL CHARACTERISTICS
VIN =12V, VEN = 5V, TA = +25C, unless otherwise noted.
Parameters
Symbol
VIN
Condition
Min
Typ
Max
Units
V
Operating Input Voltage
Supply Current (Quiescent)
4.5
28
VIN=12V, VEN=5V, no load with
switching
IQ
4
mA
Supply Current (Shutdown)
LDO Output Voltage
IST
VEN=0V, VIN=12V
2
μA
VEN=5V,
0<IVCC<10mA
7V<VIN<28V,
VCC
5.5
3.4
6
6.5
4.3
V
Input UVLO Threshold
Input UVLO Hysteresis
EN High Voltage
VIN_UVLO
Rising Edge
3.9
V
mV
V
200
VEN_HIGH
VEN_LOW
VEN Rising
VEN Falling
1.8
EN Low Voltage
0.6
V
STEP-UP CONVERTER
Gate Driver Impedance
(Sourcing)
Gate Driver Impedance
(Sinking)
VCC=6V,VGATE=6V
4
2
Ω
Ω
VCC=6V,IGATE=10mA
GATE Voltage
VGATE
fSW
6
V
R
OSC= 115kΩ
510
150
1.18
570
170
1.23
630
190
1.28
kHz
kHz
V
Switching Frequency
ROSC= 374kΩ
OSC Voltage
VOSC
TON_MIN
DMAX
PWM Mode,
when no pulse skipping happens
Minimum On Time
100
ns
Maximum Duty Cycle
ISENSE Limit
90
%
mV
μA
μA
Max Duty Cycle
175
220
65
265
COMP Source Current Limit
COMP Sink Current Limit
PWM DIMMING
ICOMP SOLI
ICOMP SILI
15
DBRT Leakage Current
BOSC Frequency
IDBRT_LK
FBOSC
IBOSC
-5
5
2
μA
kHz
uA
CBOSC=2.2nF
1.2
1.6
7.5
BOSC Output Current
LED CURRENT REGULATION
ISET Voltage
6.37
8.63
VISET
ILED
1.20
29.6
1.22
30.5
1.245
31.4
2.5
V
mA
%
LEDX Average Current
Current Matching (5)
RISET=40kꢀ
ILED=30.5mA
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
4
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
ELECTRICAL CHARACTERISTICS (continued)
VIN =12V, VEN = 5V, TA = +25C, unless otherwise noted.
Parameters
Symbol Condition
VLEDX ILED=30.5mA
Min
Typ
Max Units
LEDX Regulation Voltage
PROTECTION
600
mV
OVP Over Voltage Threshold
OVP UVLO threshold
VOVP_OV Rising Edge
1.17
50
1.23
70
1.3
90
V
mV
mV
V
VOVP_UV Step-up Converter Fails
LEDX UVLO Threshold
LEDX Over Voltage Threshold
Thermal Shutdown Threshold
VFAULT Pull Down Current
VLEDX_UV
VLEDX_OV
TST
156
5.8
196
6.3
150
55
236
6.8
℃
IFAULT
40
70
μA
VFAULT Blocking-Off Voltage
(with Respect to VIN)
VFAULT
VIN =12V, VIN-VFAULT
5.3
5.8
6.3
V
Notes:
5) Matching is defined as the difference of the maximum to minimum current divided by 2 times average currents.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
5
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
PIN FUNCTIONS
Pin #
Name
Description
1
NC
No Connect.
Supply Input. VIN supplies the power to the chip, as well as the step-up converter switch.
Drive VIN with a 5V to 28V power source. Must be locally bypassed.
2
3
VIN
The Internal 6V Linear Regulator Output. VCC provides power supply for the internal
MOSFET switch gate driver and the internal control circuitry. Bypass VCC to GND with a
ceramic capacitor.
VCC
Step-up Converter Compensation Pin. This pin is used to compensate the regulation
control loop. Connect a ceramic capacitor from COMP to GND.
4
5
COMP
EN
Enable Control Input. Do not let this pin float. It is recommended TO locally filter WITH a
0.1 μF ceramic capacitor.
Brightness Control Input. To use external PWM dimming mode, apply a PWM signal on
this pin for brightness control. To use DC input PWM dimming mode, apply a DC voltage
range from 0.2V to 1.2V on this pin linearly to set the internal dimming duty cycle from 0%
to 100%. The MP3399 has positive dimming polarity on DBRT.
6
7
8
DBRT
GND
OSC
Analog Ground.
Switching Frequency Set. Connect a resistor between OSC and GND to set the step-up
converter switching frequency. The voltage at this pin is regulated to 1.23V. The clock
frequency is proportional to the current sourced from this pin.
LED Current Set. Tie a current setting resistor from this pin to ground to program the
current in each LED string. The MP3399 regulates the voltage across the current setting
resistor. The regulation voltage is 1.22V. The proportion of the current through the ISET
resistor and the LED current is 1:1000.
9
ISET
Dimming Repetition Set. This is the timing pin for the oscillator to set the dimming
frequency. To use DC input PWM dimming mode, connect a capacitor from this pin to
GND to set the internal dimming frequency. A saw-tooth waveform is generated on this
pin. To use external PWM dimming mode, connect a resistor from this pin to GND, and
apply the PWM signal on DBRT pin.
10
BOSC
LED String 12 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 12 cathode to this pin.
11
12
13
14
15
LED12
LED11
LED10
LED9
LED String 11 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 11 cathode to this pin.
LED String 10 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 10 cathode to this pin.
LED String 9 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 9 cathode to this pin.
LED String 8 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 8 cathode to this pin.
LED8
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
6
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
PIN FUNCTIONS (continued)
Pin #
Name
Description
LED String 7 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 7 cathode to this pin.
16
LED7
LED String 6 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 6 cathode to this pin.
17
18
19
20
LED6
LED5
LED4
LED3
LED String 5 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 5 cathode to this pin.
LED String 4 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 4 cathode to this pin.
LED String 3 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 3 cathode to this pin.
LED String 2 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 2 cathode to this pin.
21
22
LED2
LED1
LED String 1 Current Input. This pin is the open-drain output of an internal dimming
control switch. Connect the LED String 1 cathode to this pin.
Over-voltage Protection Input. Connect a resistor divider from output to this pin to
program the OVP threshold. When this pin voltage reaches 1.23V, the MP3399 triggers
OV Protection mode.
23
24
OVP
Current Sense Input. During normal operation, this pin senses the voltage across the
external inductor current sensing resistor for peak current mode control and also to limit
the inductor current during every switching cycle. If this pin is not used in extending
application with other master MP3399, tie this pin to GND, do not let this pin floating.
ISENSE
25
26
PGND
GATE
Step-up Converter Power Ground.
Step-up Converter Power Switch Gate Output. This pin drives the external power N-MOS
device.
Fault Disconnection Switch Gate Output. When the system starts up normally, this pin
smoothly turns on the external PMOS. When the MP3399 is disabled, the external
27
28
VFAULT PMOS is turned off to disconnect the input and output. A ceramic cap is recommended to
add from this pin to GND to control the PMOS turn on speed so as to control the inrush
current at system start up.
NC
No Connect.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
7
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
TYPICAL PERFORMANCE CHARACTERISTICS
VIN =12V, 12 LEDs in series, 24 strings parallel, 20mA/string, unless otherwise noted.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
8
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
FUNCTION DIAGRAM
Figure 1—MP3399 Function Block Diagram
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
9
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
greater than 50 percent, a stabilizing ramp is
added to the output of the current sense amplifier
and the result is fed into the PWM comparator.
When this result voltage reaches the output
voltage of the error amplifier (VCOMP) the external
MOSFET is turned off.
OPERATION
The MP3399 employs a programmable constant
frequency, peak current mode step-up converter
and 12-channels regulated current sources to
regulate the array of 12 strings white LEDs. The
operation of the MP3399 can be understood by
referring to the block diagram of Figure 1.
The voltage at the output of the internal error
amplifier is an amplified signal of the difference
between the 600mV reference voltage and the
feedback voltage. The converter automatically
chooses the lowest active LEDX pin voltage for
providing enough bus voltage to power all the
LED arrays.
Internal 6V Regulator
The MP3399 includes an internal linear regulator
(VCC). When VIN is greater than 6.5V, this
regulator offers a 6V power supply for the internal
MOSFET switch gate driver and the internal
control circuitry. The VCC voltage drops to 0V
when the chip shuts down. In the application of
VIN smaller than 6.5V, tie VCC and VIN together.
The MP3399 features Under Voltage Lockout.
The chip is disabled until VCC exceeds the
UVLO threshold. And the hysteresis of UVLO is
approximately 200mV.
If the feedback voltage drops below the 600mV
reference, the output of the error amplifier
increases. It results in more current flowing
through the power FET, thus increasing the
power delivered to the output. In this way it forms
a close loop to make the output voltage in
regulation.
System Startup
At light-load or Vout near to Vin operation, the
converter runs into the pulse-skipping mode, the
FET is turned on for a minimum on-time of
approximately 100ns, and then the converter
discharges the power to the output in the remain
period. The external MOSFET will keep off until
the output voltage needs to be boosted again.
When the MP3399 is enabled, the chip checks
the topology connection first. The VFAULT pin
drives the external Fault Disconnection PMOS to
turn on slowly. Then the chip monitors the OVP
pin to see if the Schottky diode is not connected
or the boost output is short to GND. If the OVP
voltage is lower than 70mV, the chip will be
disabled and the external PMOS is turned off
together. The MP3399 will also check other
safety limits, including UVLO and OTP after the
OVP test is passed. If they are all in function, it
then starts boosting the step-up converter with an
internal soft-start.
Dimming Control
The MP3399 provides two PWM dimming
methods: external PWM signal or DC input PWM
Dimming mode (see Figure 2). Both methods
results in PWM chopping of the current in the
LEDs for all 12 channels to provide LED control.
DPWM
Comparator
Ex-PWM Input
DPWM Output
It is recommended on the start up sequence that
the enable signal comes after input voltage and
PWM dimming signal established.
-
+
DBRT
Step-up Converter
The
converter
operation
frequency
is
DPWM
Oscillator
programmable (from 150kHz to 500kHz) with a
external set resistor on OSC pin, which is helpful
for optimizing the external components sizes and
improving the efficiency.
BOSC
C
BOSC
At the beginning of each cycle, the external
MOSFET is turned with the internal clock. To
prevent sub-harmonic oscillations at duty cycles
Figure 2—PWM Dimming Method
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
10
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
When bias the BOSC pin to a DC level by a
The MP3399 always tries to light at least one
string and if all strings in use are open, the
MP3399 shuts down the step-up converter. The
part will maintain mark-off information until the
part shuts down.
resistor, applying an external PWM signal to the
DBRT pin to achieve the PWM dimming. A DC
analog signal can be directly applied to the DBRT
pin to modulate the LED current. And the DC
signal is then converted to a DPWM dimming
signal at the setting oscillation frequency.
Short String Protection
The MP3399 monitors the LEDX pin voltage to
judge if the short string occurs. If one or more
strings are short, the respective LEDX pins will
be pulled up to the boost output and tolerate high
voltage stress. If the LEDX pin voltage is higher
than 6.5V, the short string condition is detected
on the respective string. When the short string
fault (LEDX over-voltage fault) continues for
greater than 2048 switching clocks, the string is
marked off and disabled. Once a string is marked
off, its current regulation is forced to disconnect
from the output voltage loop regulation. The
marked-off LED strings will be shut off totally until
the part restarts. If all strings in use are short, the
MP3399 will shut down the step-up converter.
The brightness of the LED array is proportional to
the duty cycle of the DPWM signal. The DPWM
signal frequency is set by the cap at the BOSC
pin.
Open String Protection
The open string protection is achieved through
the over voltage protection. If one or more strings
are open, the respective LEDX pins are pulled to
ground and the IC keeps charging the output
voltage until it reach OVP threshold. Then the
part will mark off the open strings whose LEDX
pin voltage is less than 180mV. Once the mark-
off operation completes, the remaining LED
strings will force the output voltage back into tight
regulation. The string with the highest voltage
drop is the ruling string during output regulation.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
11
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
VOUT ILOAD(MAX)
APPLICATION INFORMATION
I
IN(MAX)
V η
IN
Selecting the Switching Frequency
I (30%~40%)I
IN(MAX)
The switching frequency of the step-up converter
is programmable from 150kHz to 500kHz. A
oscillator resistor on OSC pin sets the internal
oscillator frequency for the step-up converter
according to the equation:
Where VIN is the minimum input voltage, fSW is the
switching frequency, ILOAD(MAX) is the maximum
load current, ꢁI is the peak-to-peak inductor
ripple current and η is the efficiency.
fSW = 67850 / ROSC（kꢀ）
The switch current is usually used for the peak
current mode control. In order to avoid hitting the
current limit, the voltage across the sensing
resistor RSENSE should be less than 80% of the
worst case current limit voltage, 220mV.
For ROSC=191kꢀ, the switching frequency is set
to 355 kHz.
Setting the LED Current
The LED string currents are identical and set
through the current setting resistor on the ISET
pin.
0.80.22V
RSENSE
IL(PEAK)
ILED = 1000 x 1.22V / RSET
Where IL(PEAK) is the peak value of the inductor
current.
For RSET=60.4kꢀ, the LED current is set to 20mA.
The ISET pin can not be open.
Selecting the Power MOSFET
Selecting the Input Capacitor
The MP3399 is capable of driving a wide variety
of N-Channel power MOSFETS. The critical
parameters of selection of a MOSFET are:
The input capacitor reduces the surge current
drawn from the input supply and the switching
noise from the device. The input capacitor
impedance at the switching frequency should be
less than the input source impedance to prevent
high frequency switching current from passing
through the input. Ceramic capacitors with X5R
or X7R dielectrics are highly recommended
because of their low ESR and small temperature
coefficients. For most applications, a 4.7μF
ceramic capacitor paralleled a 220uF electrolytic
capacitor is sufficient.
1. Maximum drain to source voltage, VDS(MAX)
2. Maximum current, ID(MAX)
3. On-resistance, RDS(ON)
4. Gate source charge QGS and gate drain
charge QGD
5. Total gate charge, QG
Selecting the Inductor and Current Sensing
Resistor
Ideally, the off-state voltage across the MOSFET
is equal to the output voltage. Considering the
voltage spike when it turns off, VDS(MAX) should be
greater than 1.5 times of the output voltage.
The inductor is required to force the higher output
voltage while being driven by the input voltage. A
larger value inductor results in less ripple current,
resulting in lower peak inductor current and
reducing stress on the internal N-Channel
MOSFET. However, the larger value inductor has
a larger physical size, higher series resistance,
and lower saturation current.
The maximum current through the power
MOSFET happens when the input voltage is
minimum and the output power is maximum. The
maximum RMS current through the MOSFET is
given by
Choose an inductor that does not saturate under
the worst-case load conditions. A good rule for
determining the inductance is to allow the peak-
to-peak ripple current to be approximately 30% to
40% of the maximum input current. Calculate the
Where:
IRMS(MAX) IIN(MAX) DMAX
VOUT V
IN(MIN)
DMAX
VOUT
required inductance value by the equation:
The current rating of the MOSFET should be
greater than 1.5 times IRMS
V (VOUT V )
IN
IN
L
VOUT fSW ∆I
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
12
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
The on resistance of the MOSFET determines
Setting the Over Voltage Protection
the conduction loss, which is given by:
The open string protection is achieved through
the over voltage protection (OVP). In some cases,
an LED string failure results in the feedback
voltage always zero. The part then keeps
boosting the output voltage higher and higher. If
the output voltage reaches the programmed OVP
threshold, the protection will be triggered.
2
Pcond IRMS RDS (on) k
Where k is the temperature coefficient of the
MOSFET.
The switching loss is related to QGD and QGS1
which determine the commutation time. QGS1 is
the charge between the threshold voltage and
the plateau voltage when a driver charges the
gate, which can be read in the chart of VGS vs. QG
of the MOSFET datasheet. QGD is the charge
during the plateau voltage. These two
parameters are needed to estimate the turn on
and turn off loss.
To make sure the chip functions properly, the
OVP setting resistor divider must be set with a
proper value. The recommended OVP point is
about 1.2 times higher than the output voltage for
normal operation.
VOVP=1.23V*(R1+R2)/R2
Selecting Dimming Control Mode
The MP3399 provides 2 different dimming
methods
QGS1 RG
PSW
VDS IIN fSW
VDS IIN fSW
VDR VTH
QGD RG
VDR VPLT
1. Direct PWM Dimming
An external PWM dimming signal is employed to
achieve PWM dimming control. Connect a 100kꢀ
resistor from BOSC pin to GND and apply the
100Hz to 2kHz PWM dimming signal to DBRT
pin. The minimum recommended amplitude of
the PWM signal is 1.2V (See Figure 3).
Where VTH is the threshold voltage, VPLT is the
plateau voltage, RG is the gate resistance, VDS is
the drain-source voltage. Please note that the
switching loss is the most difficult part in the loss
estimation. The formula above provides a simple
physical expression. If more accurate estimation
is required, the expressions will be much more
complex.
For extended knowledge of the power loss
estimation, readers should refer to the book
“Power MOSFET Theory and Applications”
written by Duncan A. Grant and John Gowar.
Figure 3—Direct PWM Dimming
The total gate charge, QG, is used to calculate
the gate drive loss. The expression is
2. DC Input PWM Dimming
PDR QG VDR fSW
To apply DC input PWM dimming, apply an
analog signal (range from 0 V to 1.2V) to the
DBRT pin to modulate the LED current directly. If
the PWM is applied with a zero DC voltage, the
PWM duty cycle will be 0%. If the DBRT pin is
applied with a DC voltage>1.2V, the output will
be 100% (See Figure 4). The capacitor on BOSC
pin set the frequency of internal triangle
waveform according to the equation,:
Where VDR is the drive voltage.
Selecting the Output Capacitor
The output capacitor keeps the output voltage
ripple small and ensures feedback loop stability.
The output capacitor impedance should be low at
the switching frequency. Ceramic capacitors with
X7R dielectrics are recommended for their low
ESR characteristics. For most applications, a
4.7μF ceramic capacitor paralleled 10uF
electrolytic capacitor will be sufficient.
F
UNITE = 3.5μF / CUNITE
The dimming frequency is recommended set
from 100Hz to 2kHz.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
13
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
Layout Considerations
Careful attention must be paid to the PCB board
layout and components placement. Proper layout
of the high frequency switching path is critical to
prevent noise and electromagnetic interference
problems. The loop of external MOSFET (M2),
output diode (D1), and output capacitor (C5) is
flowing with high frequency pulse current. It must
be as small as possible (See Figure 5).
Figure 4—DC input PWM Dimming
Extending LED Channels applications
The MP3399 is flexible for extending LED
channels with two or more MP3399s in parallel.
For the connection of two MP3399s extending 24
strings LEDs, please see the typical application
diagram in page 2. Tie the VCC pins of the
master IC and the slave IC together to provide
the power of the slave IC internal logic circuitry.
Also tie the COMP pins of the slave IC and the
master IC together to regulate the voltage of all
24 strings LEDs. The MOS driving signals of the
slave IC are not used, the boost converter can be
only driven by the master IC. Do not let the
Isense pin of the slave IC floating, tie it to GND.
The EN and Dimming signals should be applied
to both ICs. It is recommended to use external
PWM dimming mode to achieve the accurate
dimming synchronization of both parts.
Figure 5—Layout Consideration
The IC exposed pad is internally connected to
GND pin, and all logic signals are refer to the
GND. The PGND should be externally connected
to GND and is recommended to keep away from
the logic signals.
External MOSFET for Short Protection
When output voltage is higher than rating of
LED1-12 pins, external MOSFET is needed for
each LED channel to avoid destroying LED1 -12
pins. (See Figure 8 for 4 channels application)
The rating of MOSFET must be higher than 1.2*
VOUT t and more than 1.2* ILED.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
14
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
TYPICAL APPLICATION CIRCUIT
L1
M1
D1
8V-28V
VIN
14S 12P 20mA
C3
C13
C16
AM4499P
B180
F1
LED+
C1
C2
NC
C10
NC
R26
NC
LED1
LED2
LED3
LED4
LED5
LED6
LED7
LED8
LED9
LED10
LED11
LED12
C17
5.6nF
R51
499k
C15
R20
10
R11
0
C12
NC
GND
GND
GND
GND
M2 AM4490N
GND
GND
GND
U1
2
3
27
26
24
28
25
23
22
21
20
19
18
17
16
15
R54
10k
R22
0
VIN
VFAULT
C14
100pF
R53
10k
VCC
GATE
ISENSE
NC
C9
R15
4
COMP
EN
R1
2k
C4
GND
GND
R24
0.05
R25
NC
220nF
0
5
EN
8
R4
20k
C18
OSC
PGND
OVP
R13
GND
340k
1
NC
GND
R27
R28
R29
R30
R31
R32
R33
R34
R35
R36
R37
R38
0
0
0
0
0
0
0
0
0
0
0
0
GND
10
7
BOSC
GND
LED1
LED2
LED3
LED4
LED5
LED6
LED7
LED8
R8
100k
C6
NC
MP3399
R2
2k
GND
6
NET00016
DBRT
ISET
DIMMING
R16
9
R5
20k
60.4k
GND
11
12
13
14
LED12
LED11
LED10
LED9
GND
Figure 6—Drive 14 LEDs in Series, 12 Strings 20mA/string
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
15
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
L1
M1
AM4499P
D1
B180
8V-28V
VIN
12S 12/24 P 20mA
C1 C2
NC
C3
VIN
C13
C16
F1
LED+
R51
357k
C10
NC
R26
NC
LED1
LED2
LED3
LED4
LED5
LED6
C17
VCC
5.6nF
OVP1
C15
R11
0
GND
R20
10
VFAULT
C12
NC
GND
GND
GND
R52
1k
GND
GND
GND
U1
M2 AM4490N
2
27
26
24
28
25
23
22
21
20
19
18
17
16
15
LED7
R54
10k
VIN
VFAULT
GATE
ISENSE
NC
R22
0
LED8
VCC
R53
10k
3
C14
100pF
LED9
VCC
R23
NC
C9
LED10
LED11
LED12
COMP
4
GND
COMP
R15
GND
R1
2k
C4
220nF
R25
NC
0
GND
5
R24
0.05
EN
EN
8
OSC
PGND
OVP
C18
R4
20k
R13
340k
GND
1
NC
GND
R27
R28
R29
R30
R31
R32
R33
R34
R35
R36
R37
R38
0
0
0
0
0
0
0
0
0
0
0
0
GND
10
BOSC
LED1
LED2
LED3
LED4
LED5
LED6
LED7
LED8
R8
100k
C6
NC
MP3399
7
GND
R2
2k
GND
6
DBRT
DIMMING
R16
9
R5
20k
ISET
60.4k
GND
11
LED12
GND
12
LED11
13
LED10
14
LED9
VCC
VIN
VFAULT
R19
NC
R21
NC
R12
0
U2
2
27
26
24
28
25
23
22
21
20
19
18
17
16
15
VIN
VFAULT
GATE
ISENSE
NC
LED13
LED14
LED15
LED16
LED17
LED18
3
VCC
COMP
C7
NC
R17
NC
GND
4
COMP
R7
0
5
EN
OVP1
LED19
LED20
LED21
LED22
LED23
LED24
8
OSC
PGND
OVP
R14
340k
C11
100pF
GND
1
NC
R39
R40
R41
R42
R43
R44
R45
R46
R47
R48
R49
R50
0
0
0
0
0
0
0
0
0
0
0
0
GND
GND
10
BOSC
LED1
LED2
LED3
LED4
LED5
LED6
LED7
LED8
R9
100k
C8
NC
MP3399
7
GND
GND
6
DBRT
R18
9
ISET
60.4k
GND
11
LED12
12
LED11
13
LED10
14
LED9
Figure 7—Drive 12 LEDs in Series, 24 Strings 20mA/string
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
16
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
L1
M1
D1
8V-28V
VIN
C3
C13
C16
18S 4P 60mA
AM4499P
B180
F1
LED+
C1
C2
NC
C10
NC
R26
NC
C17
5.6nF
R51
499k
C15
R11
0
R20
10
C12
NC
GND
GND
GND
GND
M2 AM4490N
GND
GND
GND
U1
2
3
27
26
24
28
25
23
22
21
20
19
18
17
16
15
R54
10k
R22
0
VIN
VFAULT
C14
100pF
R53
10k
VCC
GATE
ISENSE
NC
C9
R15
4
COMP
EN
R1
2k
C4
GND
GND
R24
0.05
R25
NC
220nF
0
5
EN
LED1
LED2
LED3
LED4
8
R4
20k
C18
OSC
PGND
OVP
R13
340k
GND
1
NC
GND
R27
R28
R29
R30
R31
R32
R33
R34
R35
R36
R37
R38
0
0
0
0
0
0
0
0
0
0
0
0
GND
10
7
BOSC
GND
LED1
LED2
LED3
LED4
LED5
LED6
LED7
LED8
M3
M4
R8
100k
C6
NC
MP3399
R2
2k
GND
6
NET00016
DBRT
ISET
DIMMING
R16
9
R5
20k
60.4k
GND
11
12
13
14
LED12
LED11
LED10
LED9
GND
M3-M6: AM3490N 100V/1A TSOP6
M5
M6
VIN
R39
0
R40
NC
GND
Figure 8 – Drive 18LEDs in Series, 4 strings 60mA/string
Note: For Vin>15V application, use R139 and R40(10kΩ) divider to make a 15V bias voltage for M3-M6.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
17
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
PACKAGE INFORMATION
PACKAGE OUTLINE DRAWING FOR 28-TSSOP w/ EXPOSED PADDLE
5.90
TYP
0.65
BSC
9.60
9.80
0.40
TYP
28
15
1.60
TYP
4.30
4.50
3.20 5.80
TYP TYP
6.20
6.60
PIN 1 ID
14
1
TOP VIEW
RECOMMENDED LAND PATTERN
0.80
1.05
1.20 MAX
SEATING PLANE
0.09
0.20
0.19
0.30
0.00
0.15
0.65 BSC
SEE DETAIL "A"
FRONT VIEW
SIDE VIEW
GAUGE PLANE
0.25 BSC
5.70
6.10
0.45
0.75
0o-8o
DETAIL “A”
2.60
3.10
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 AET.
6) DRAWING IS NOT TO SCALE.
BOTTOM VIEW
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
18
MP3399-12-STRING, CASCADING WHITE LED DRIVER WITH STEP-UP CONTROLLER
PACKAGE INFORMATION
SOIC28
NOTICE: The information in this document is subject to change without notice. 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.
MP3399 Rev. 1.1
5/23/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
19
相关型号：
MP3410DJ-LF-Z
Switching Regulator, Current-mode, 1.5A, 690kHz Switching Freq-Max, PDSO5, ROHS COMPLIANT, MO-193AA, TSOT-23, 5 PIN
MPS
MP3410DJ-Z
Switching Regulator, Current-mode, 1.5A, 690kHz Switching Freq-Max, PDSO5, MO-193AA, TSOT-23, 5 PIN
MPS
©2020 ICPDF网 联系我们和版权申明