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General Description
The RT9362/A is a high efficiency charge pump white LED driver. It supports up to 4 white LEDs with regulated constant current for uniform intensity. The RT9362/A maintains the highest efficiency by utilizing a x1/x1.5/x2 fractional charge pump and low dropout current regulators. User can easily configure each LED current up 30mA by an external resistor. Two digital inputs can be programmable to control white LED On/Off. LED dimming can be achieved by applying a PWM signal to the digital control signals.
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Features
RT9362/A
White LED Driver (120mA Charge Pump with Current Source)
Very High Efficiency Over 90% of Battery Life Support up to 4 WLEDs Support up to 120mA Output Current Soft Start Function Short Circuit Protection Function Three Charge Pump Mode: x1, x1.5, x2 250k/1MHz Fixed Frequency Oscillator RoHS Compliant and 100% Lead (Pb)-Free
Applications
The operating voltage range is 2.5V to 5.5V. Internal softstart circuitry effectively reduces the in-rush current both while start-up and mode change. RT9362/A also provides comprehensive protections such short circuit protection and over-temperature protection. The load is disconnected from VIN while shutdown and the shutdown current is less than 1uA. RT9362/A is available in a QFN-16L 3x3 package.
Mobile Phone White LED Backlighting Camera Flash LED Lighting
Marking Information
Ordering Information
RT9362/A Package Type QV : QFN-16L 3x3 (V-Type)
Operating Temperature Range P : Pb Free with Commercial Standard 250kHz 1MHz
Note :
RichTek Pb-free products are :
CTRL0
CTRL1
EN
ments of IPC/JEDEC J-STD-020. -Suitable for use in SnPb or Pb-free soldering processes. -100%matte tin (Sn) plating.
AGND
-RoHS compliant and compatible with the current require-
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PGND
C2N
12 11 10 9
C1N
8 C1P 7 VIN 6 VOUT 5 ISET 4
LED4 13 LED3 14 LED2 15 LED1 16
1 2 3
C2P
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For marking information, contact our sales representative directly or through a RichTek distributor located in your area, otherwise visit our website for detail.
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Pin Configurations
(TOP VIEW)
GND
QFN-16L 3x3
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RT9362/A
Typical Application Circuit
C1
8 9 11
C2
10
C1P
7
+ Li-ion Battery
CIN 1uF
VIN
C1N C2P C2N 6 VOUT COUT 1uF LED1 15 LED2 14 LED3 13 LED4
16
High Low
1 EN RT9362/A 2 CTRL0 3 CTRL1 4
AGND 5 ISET
RSET
PGND
12
Figure 1. For 2-WLEDs back light.
C1
8 9 11
C2
10
C1P
7
VIN
C1N C2P C2N 6 VOUT COUT 1uF LED1 15 LED2 14 LED3 13 LED4
16
+ Li-ion Battery
CIN 1uF
High Low
1 EN RT9362/A 2 CTRL0 3 CTRL1 4
AGND 5 ISET
20mA 20mA
RSET
PGND
12
RSET =
10mA channel
Figure 2. For 2-WLEDs back light.
C1
8 9 11
C2
10
C1P
7
VIN
C1N C2P C2N 6 VOUT COUT 1uF LED1 15 LED2 14 LED3 13 LED4
16
+ Li-ion Battery
CIN 1uF
High Low
1 EN RT9362/A 2 CTRL0 3 CTRL1 4 5
AGND ISET
RSET
PGND
12
Figure 3. For 3-WLEDs back light.
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RT9362/A
C1
8 9 11
C2
10
C1P
7
VIN
C1N C2P C2N 6 VOUT COUT 1uF LED1 15 LED2 14 LED3 13 LED4
16
+ Li-ion Battery
CIN 1uF
High Low
1 EN RT9362/A 2 CTRL0 3 CTRL1 4 5
AGND ISET
RSET
PGND
12
Figure 4. For 4-WLEDs back light.
VDD
Base Band
GPIO1 GPIO2
RADJ
High : VDD (Movie Mode) Low : 0V (Strobe Mode)
VIN CIN 1uF
VOUT C1P ISET VIN
RSET C1 9 10 C2 C1N C2N 8 7 6 5 AGND 4 3
CTRL1 RT9362/A
11 C2+
LED4
CTRL0 2
LED1
LED3
LED2
12 PGND
EN
1 100k
13
14
15
16
Flash LED COUT 1uF
Figure 5. For 3-WLEDs camera flash module.
Table 1
C1 (uF) RT9362 RT9362A 0.1 0.47 C2 (uF) 0.1 0.47
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RT9362/A
Functional Pin Description
Pin Number Pin Name 1 2 3 4 5 6 7 8 9 10 11 12 13 to 16 Exposed Pad EN CTRL0 CTRL1 AGND ISET VOUT VIN C1P C1N C2N C2P PGND GND Pin Function Chip Enable (Active High). Note that this pin is high impedance. There should be a pull low 100k resistor connected to GND when the control signal is floating. Output Control Bit 0. (See Table 2) Output Control Bit 1. (See Table 2) Analog Ground LED current is set by the value of the resistor RSET connected from the ISET pin to ground. Do not short the ISET pin. VISET is typically 1.1V. All external capacitance at this pin, including board parasitic capacitance, must be less than or equal to 30pF. Output Voltage Source for connection to the LED anodes. Input Voltage Positive Terminal of Bucket Capacitor 1 Negative Terminal of Bucket Capacitor 1 Negative Terminal of Bucket Capacitor 2 Positive Terminal of Bucket Capacitor 2 Power Ground. Exposed pad should be soldered to PCB board and connected to GND.
LED 4 to 1 Current Sink for LED. (If not in use, pin should be connected to VOUT)
Function Block Diagram
C1N C2P C2N C1P
VIN PGND
x1/x1.5/x2 Charge Pump
250k/1MHz Oscillator
VOUT
AGND Mode Decision I-Setting IS ISET LED1 EN Bandgap VREF LED2 IS LED3 LED4 CTRL0 CTRL1
Decoder
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RT9362/A
Operation
The RT9362/A is a high efficiency charge pump white LED driver. It provides 4 channels low drop-out voltage current source to regulated 4 white LEDs current. For high efficiency, the RT9362/A implements x1/x1.5/x2 mode charge pump. An external RSET is used to set the current of white LED. RT9362/A has an input current regulation to reduce the input ripple. Soft Start The RT9362/A includes a soft start circuit to limit the inrush current at power on and mode switching. Soft start circuit holds the input current level long enough for output capacitor COUT reaching a desired voltage level. When the soft start off, the RT9362/A won' t sink spike current from V IN. Mode Decision The RT9362/A uses a smart mode decision method to select the working mode for maximum efficiency. Mode decision circuit senses the output and LED voltage for up/down selection. Dimming Control CTRL0 and CTRL1 are used to control the on/off of White LED. When an external PWM signal is connected to the control pin, brightness of white LED is adjusted by the duty cycle. LED Current Setting The current of white LED connected to RT9362/A can be set by RSET. Every current flows through the white LED is 440 times greater than the current of RSET. The white LED can be estimated by following equation: VISET ILED = 440 x RSET where VISET = 1.1V, and RSET is the resistance connected from ISET to GND. Thermal Shutdown The RT9362/A provides a high current capability to drive 4 white LEDs. A thermal shutdown circuit is needed to protect the chip from thermal damage. When the chip reaches the shutdown temperature 150C, the thermal shutdown circuit turns off the chip to prevent the thermal accumulation in the chip. Overvoltage Protection The RT9362/A regulates the output voltage by controlling the input current. When the output voltage reaches the designated level, the RT9362/A reduces the input current. And then, the output voltage regulation also serves an over-voltage protection. Short Circuit Protection A current limiting circuit is also included in the RT9362/A for short circuit protection. Whenever output source a dangerously high current, the current limiting circuit takes over the output regulation circuit and reduces the output current at an acceptable level.
Table 2
Control Inputs CTRL 1 0 0 1 1 CTRL 0 0 1 0 1 LED 4 OFF OFF ON OFF
Output Status LED 3 OFF ON ON OFF LED 2 ON ON ON OFF LED 1 ON ON ON OFF
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RT9362/A
Absolute Maximum Ratings
(Note 1) Input Voltage -------------------------------------------------------------------------------------------------------------- -0.3 to 6V Output Voltage ----------------------------------------------------------------------------------------------------------- -0.3 to 6V Power Dissipation, PD @ TA = 25C QFN-16L 3X3 ------------------------------------------------------------------------------------------------------------- 1.47W Package Thermal Resistance (Note 4) QFN-16L 3x3, JA ------------------------------------------------------------------------------------------------------- 68C/W Junction Temperature --------------------------------------------------------------------------------------------------- 150C Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------------------- 260C Junction Temperature Range ------------------------------------------------------------------------------------------ -40C to 125C Storage Temperature Range ------------------------------------------------------------------------------------------ -65C to 150C ESD Susceptibility (Note 2) HBM (Human Body Mode) -------------------------------------------------------------------------------------------- 2kV MM (Machine Mode) ---------------------------------------------------------------------------------------------------- 200V
Recommended Operating Conditions Electrical Characteristics
(Note 3)
Ambient Temperature Range ------------------------------------------------------------------------------------------ -40C to 85C
(VIN = 2.85V to 5.5V, C1 = C2 = 1.0F (ESR = 0.03, TA = 25C, unless otherwise specified)
Parameter Input Supply Voltage Undervoltage Lockout Threshold Undervoltage Lockout Hysteresis
Symbol VIN
Test Conditions
Min 2.5
Typ -2.2 50 20 5 --3 1.5 1 2 1 3.8 2.8 1.0 250 --
Max 5.5 2.4 ---20 30 --7 7.5 5 --1.2 300 850
Units V V mV mA mA mA mA mA mA uA % % V V MHz kHz mA
VIN rising or falling
1.8 --
RSET = 24.0K Current into LEDs 1, 2, 3 and 4 ILED RSET = 91.0K 2.7V < VIN < 5.5V 3.1V < VIN < 5.5V RT9362 Quiescent Current RT9362A RT9362/A ILED Accuracy Current Matching x1 mode to x1.5 mode Transition Voltage (VIN falling) x1.5 mode to x2 mode Transition Voltage (VIN falling) Oscillator Frequency Input Current Limit ILED-ERR IQ FOSC =1MHz, EN = High, No Load FOSC =250kHz, EN = High, No Load VIN = 4.2V, EN = Low 2mA < ILED < 30mA ILED-LED-ERR 2mA < ILED < 30mA VLED= 3.6V, IOUT= 80mA ILED1 = ILED2 = ILED3 = ILED4 = 20mA VLED= 3.6V, IOUT= 80mA VTRANS1.5X ILED1 = ILED2 = ILED3 = ILED4 = 20mA VTRANS1X FOSC FOSC ILIM RT9362 RT9362A Short Circuit applied from VOUT to GND
--2 2 -------0.8 200 450
To be continued
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RT9362/A
Parameter Output Over Voltage Protection Symbol VOVP VIH VIL IIH IIL Test Conditions Open circuit at any LED that is programmed to be in the ON state Input high logic threshold (EN, CTRL0, CTRL1) Input low logic threshold (EN, CTRL0, CTRL1) VIH = VIN VIL = GND Min -Typ 5.5 Max 6 Units V
Input High Threshold Input Low Threshold Input High Current Input Low Current Thermal Shutdown Threshold Thermal Shutdown Hysteresis
1.5 ------
----150 10
-0.4 1 1 ---
V V uA uA C C
Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2. Devices are ESD sensitive. Handling precaution recommended. Note 3. The device is not guaranteed to function outside its operating conditions. Note 4. JA is measured in the natural convection at T A = 25C on a low effective thermal conductivity test board of JEDEC 51-3 thermal measurement standard. Note 5.
ILED Accuracy =
ILED(MEASURED) - ILED (SET) x 100% ILED(SET)
Note 6. Current Matching refers to the difference in current from on LED to the next.
ILED Current Matching =
ILED(MAX) - ILED (MIN) x 100% ILED(MAX) + ILED (MIN)
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RT9362/A
Typical Operating Characteristics
For RT9362, TA = 25C,unless otherwise specified. UVLOInput Voltage vs. Temperature Threshold Voltage vs. Temperature
Quiescent Current vs. Input Voltage
5
UVLO Threshold Voltage (V) Input Voltage (V)
2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5
POR
Quiescent Current (mA)
4
X1.5 Mode
3
POF
2
X1 Mode
1
0
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
2.5
3
3.5
4
4.5
5
5.5
Temperature (C)
Input Voltage (V)
Logic Threshold Voltage vs. Input Voltage
1.4 1.3
23 22
LED Current vs. Input Voltage
Logic Threshold (V)
LED Current (mA)
1.2 1.1 1.0 0.9 0.8 0.7 2.5 3.0 3.5 4.0
VIH
T = 25C
21 20 19 18 17
T = 85C
VIL
T = -40C
4.5
5.0
5.5
5.5
5.0
4.5
4.0
3.5
3.0
2.5
Input Voltage (V)
Input Voltage (V)
Efficiency vs. Input Voltage (LED)
95 90 85
Efficiency vs. InputInput Voltage Efficiency vs. Voltage (Converter)
100 98 96 94
IOUT = 80mA, VF = 3.2V
IOUT = 80mA, VF = 3.2V
Efficiency (%)
Efficiency (%)
5.5 5 4.5 4 3.5 3 2.5 2
80 75 70 65 60 55 50
92 90 88 86 84 82 80 5.5 5 4.5 4 3.5 3 2.5 2
Input Voltage (V)
Input Voltage (V)
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RT9362/A
Inrush Current (EN High)
(100mV/Div)
Inrush Current (EN High)
VIN
(100mV/Div)
VIN
(5V/Div)
VOUT
(2V/Div)
VOUT
(5V/Div)
EN
EN
(2V/Div)
I IN
(200mA/Div)
I IN
VIN = 3.0V, ILED = 20mA
(200mA/Div) VIN = 4.3V, ILED = 20mA
Time (20s/Div)
Time (20s/Div)
Mode Change Inrush Current ( x1 to x1.5)
VOUT VIN
(2V/Div) (100mV/Div)
Normal Operation (x2 Mode)
VIN C1P
(2V/Div) (2V/Div)
C1P
(2V/Div)
C2P
(2V/Div)
I LED
(10mA/Div)
I IN
(200mA/Div) ILED = 20mA VIN = 2.5V, ILED = 20mA
Time (10s/Div)
Time (1s/Div)
Normal Operation (x1.5 Mode)
VIN VOUT C1P
(2V/Div) (2V/Div)
Normal Operation (x1 Mode)
VIN VOUT C1P
(2V/Div) (2V/Div) (2V/Div)
(2V/Div)
I LED
(10mA/Div)
I LED
(10mA/Div)
VIN = 2.7V, ILED= 20mA
VIN = 5.5V, ILED= 20mA
Time (1s/Div)
Time (1s/Div)
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RT9362/A
Normal Operation
(2V/Div)
Normal Operation
VIN VOUT I LED C1P
(2V/Div) (2V/Div) (10mA/Div) (2V/Div)
VIN VOUT I LED C1P
(2V/Div) (10mA/Div)
(2V/Div)
VIN = 3.1V, ILED= 30mA
VIN = 5.5V, ILED= 30mA
Time (1s/Div)
Time (1s/Div)
Dimming Operation
(2V/Div)
Dimming Operation
CTRL0 VOUT C1P
(2V/Div) (2V/Div) (2V/Div)
CTRL0 VOUT C1P
(2V/Div) (2V/Div)
I LED
(10mA/Div)
I LED
VIN = 3.0V, Duty = 20%
(10mA/Div)
VIN = 3.0V, Duty = 80%
Time (400s/Div)
Time (400s/Div)
Dimming Operation
(2V/Div)
Dimming Operation
CTRL0 VOUT C1P
(2V/Div) (2V/Div) (2V/Div)
CTRL0 VOUT C1P
(2V/Div) (2V/Div)
I LED
(10mA/Div)
I LED
VIN = 4.3V, Duty = 20%
(10mA/Div)
VIN = 4.3V, Duty = 80%
Time (400s/Div)
Time (400s/Div)
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RT9362/A
Applications Information
Selecting Capacitors To get the better performance of RT9362/A, the selecting of peripherally appropriate capacitor and value is very important. These capacitors determine some parameters such as input and output ripple, power efficiency, maximum supply current by charge pump, and start-up time. To reduce the input and output ripple effectively, the low ESR ceramic capacitors are recommended. Generally, to reduce the output ripple, increasing the output capacitance COUT is necessary. However, this will increase the start-up time of output voltage. For LED driver applications, the input voltage ripple is more important than output ripple. Input ripple is controlled by input capacitor C IN , increasing the value of input capacitance can further reduce the ripple. Practically, the input voltage ripple depends on the power supply's impedance. If a single input capacitor CIN cannot satisfy the requirement of application, it is necessary to add a low-pass filter as shows in Figure 1.
1 2.2uF RT9362/A VIN
Figure 2 shows the typical value of RSET versus average LED current and Table 3 shows the values of RSET for a fixed LED current.
100 90 80 70
R SET (k)
60 50 40 30 20 10 0 0 5 10 15 20 25 30
LED average current (mA)
Figure 2. The typical curve of RSET vs. LED's average current. Table 3. RSET Value Selection
ILED (mA) 5 10 15 20 25 30 RSET (k) 91.0 47.9 32.7 24.0 19.6 16.4 Nearest Standard Values for RSET (k) 91.0 47.5 32.4 24.0 19.6 16.5
VIN 2.2uF
Frgure1. C-R-C filter used to reduce input ripple The flying capacitor C1 and C2 determine the supply current capability of the charge pump and to influence the overall efficiency of system. The lower value will improve efficiency, but it will limit the LED' s current at low input voltage. Setting the LED Current The RT9362/A can be set a fixed LEDs current by a resister RSET connected from ISET to GND. RSET establishes the reference current and mirrors the current into LED1, LED2, LED3, and LED4. The current into LED is about 440 times of the current flows through the RSET, the approximate setting formula is given as follows:
If maximum accuracy is required, a precision resister is needed. Equation (2) shows how to calculate the error ILED(ERR).
ILED(ERR) =
ILED(MEA) - ILED(SET) ILED(SET)
x 100%
(2)
Where ILED(MEA) is practical LED current ILED(SET) is LED current which is determined by the RSET.
ILED (A) =
484 (V) RSET ()
(1)
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RT9362/A
LED current setting with NMOS LED current setting control can also be achieved by using the external NMOS to change equivalent resister of ISET pin. Figure 3 shows this application circuit of method. For this example, a 3 bit signals can set 8 kinds of different equivalent resister of ISET pin, i.e. produce 8 kinds of LED current level. Table 4 shows the relation between equivalent resister of ISET pin and control signal.
RT9362/A ISET R4 R2 S2 R3 S3 S1 R1
CTRLx and 4 LED's current states. For an example, as the CTRL1 is pulled logical high and CTRL0 receives a PWM signal, then, four LEDs will be dimmed synchronously. Here, the PWM signal setting the LED's current ON/OFF can achieve the average LED's current which in design. The application circuit is shown in Figure 4. Figure 5, and Figure 6 show 3WEDs and 2WLEDs PWM dimming application circuit, respectively. During the time of PWM signal logical low, the current is a fixed value and setting by RSET resistor. So the average LEDs current can be approximated as Equation (3).
ILED(AVG) = TOFF x ILED(ON) TPWM
(3)
Where: TPWM is the period of PWM dimming signal TOFF is the time of PWM signal at low. ILED(ON) is LED on state current. Table 5. The relation between CTRLx and 4 LED's current states
Control Inputs CTRL1 0 0 1 1 CTRL0 0 1 0 1 LED4 O FF O FF ON O FF O utput Status LED3 O FF ON ON O FF LED2 ON ON ON O FF LED1 ON ON ON O FF
Figure 3. The application circuit of setting LED current which using a NMOS to set RSET. Table 4. The relation between control signal and equivalent resister of ISET pin
S1 0 0 0 0 1 1 1 1 S2 0 0 1 1 0 0 1 1 S3 0 1 0 1 0 1 0 1 Equivalent Resister of ISET pin (RSET) RSET = R4 RSET = R3//R4 RSET = R2//R4 RSET = R2//R3//R4 RSET = R1//R4 RSET = R1//R3//R4 RSET = R1//R2//R4 RSET = R1//R2//R3//R4
RT9362/A CTRL1 CTRL0 EN VIN PWM GPIO LED LED ON OFF
Figure 4. The PWM dimming application circuit for 4WLEDs
LED Dimming Control Methods The RT9362/A can use two methods to achieve the LED dimming control. These methods are detailed described as following:
(1). Dimming using PWM signal into CTRL0 and CTRL1
RT9362/A CTRL1 CTRL0 EN PWM VIN GPIO
LED LED ON OFF
LED current can be controlled by applying a PWM signal to CTRL0 or CTRL1. Table 5 shows the relation between
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Figure 5. The PWM dimming application circuit for 3WLEDs
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RT9362/A
RT9362/A CTRL1 CTRL0 EN GPIO PWM LED LED ON OFF
(2). The PWM dimming by GPIO
Figure 6. The PWM dimming application circuit for 2WLEDs Besides, RT9362/A has 100us delay time between mode transfer. This delay time makes different dimming frequency corresponds to different maximum duty of CTRLX pin. When the duty cycle of dimming frequency excess maximum duty, the RT9362/As can't transfer the mode normally. Equation (4) shows the relation between maximum duty of CTRLX pin and PWM dimming frequency. Table 6 is shown the common dimming frequency and its corresponding maximum duty. For better performance consideration, the maximum PWM dimming frequency is recommended below 1kHz.
D(MAX) = (1- 100 x 10 -6 x FD )
The PWM dimming by GPIO is shown as Figure 7. DZ shall be a Schottky diode with forward voltage less than 0.3V at IF = 1mA. C3 is a capacitor to keep the enable pin voltage is higher than the threshold voltage. R1 is discharge resister and it should be not too high to prevent the off time too long while turned-off. The recommended conditions are shown as following. 1. The recommended value for R1 and C3 are 200k (5%) and 0.22uF (X7R, 10%). 2. The forward voltage of the Schottky diode shall be less than 0.3V at 1mA. 3. The output voltage of GPIO should be greater than 2.8V and keep the voltage on EN pin is higher than 1.5V. 4. The PWM frequency should be in the range of 500Hz~1.5kHz or 20kHz~30kHz for audio noise consideration. 5. The PWM duty cycle shall be in the range of 30% to 95%. 6. The driving capability of the GPIO should be greater than 2mA @ 2.8V. 7. The LED current can be obtained by the equation, VISET ILED = 440 x x (1 - DPWM ) R SET (The typical value of VISET is 1.1V)
(4)
Where : DMAX is Maximum Duty of CTRLX FD is PWM Dimming Frequency Table 6. The common dimming frequency and its corresponding maximum duty.
Dimming Frequency (Hz) 1K 900 800 700 600 500 400 300 200 CTRLX Maximum Duty 0.90 0.91 0.92 0.93 0.94 0.95 0.96 0.97 0.98 ILED Minimum Duty 0.10 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02
PWM Signal VDD 2.8V GPIO RSET VIN DZ
VEN>1.5V C3 R1
RT9362/A ISET CTRL1 CTRL0 EN
Figure 7. The GPIO PWM dimming application circuit
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RT9362/A
20 18 16
LED Current (mA)
14 12 10 8 6 4 2 0 30 40 50 60 70 80 90 100
GPIO PWM Duty (%)
Figure 8. GPIO PWM dimming duty v.s. ILED current (RSET = 19k)
PCB Board Layout The RT9362/A is a high-frequency switched-capacitor converter. For best performance, place all of the components as close to IC as possible. Besides a solid ground plane is recommended on the bottom layer of the PCB. The ground should be connected CIN and COUT together and as close to the IC as possible. Figure 9 shows the typical layout of RT9362/A' s EVB board.
Top Layer
Bottom Layer Figure 11. Typical layout of RT9362/A' s EVB board
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RT9362/A
Outline Dimension
D
D2 L
1
E
E2
e A A1 A3
b
Symbol A A1 A3 b D D2 E E2 e L
Dimensions In Millimeters Min 0.800 0.000 0.175 0.180 2.950 1.500 2.950 1.500 0.500 0.350 0.450 Max 1.000 0.050 0.228 0.300 3.050 1.750 3.050 1.750
Dimensions In Inches Min 0.031 0.000 0.007 0.007 0.116 0.059 0.116 0.059 0.020 0.014 0.018 Max 0.039 0.002 0.009 0.012 0.120 0.069 0.120 0.069
V-Type 16L QFN 3x3 Package
RICHTEK TECHNOLOGY CORP.
Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611
RICHTEK TECHNOLOGY CORP.
Taipei Office (Marketing) 8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek.com
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