ANPEC APW7000

APW7000
1X/1.5X/2x Charge Pump White LED Driver
General Description
Features
±1.5% LED Current Matching
The APW7000 is a high efficiency charge pump white
High Efficiency Up to 90% Over Li-ion Battery
LED driver; the device drives up to four white LEDs with
regulated constant current for uniform intensity. The sup-
Discharge
Output Current Up to 30mA Per LED
1.5x, and 2x charge pump modes and automatically
switches the charge pump modes depend on the input
2.7V to 5.5V Operating Voltage
Allow to Turn On or Off a Combination of LEDs
voltage to maintain the required power for high power
efficiency. The APW7000 provides up to 30mA per LED,
1x/1.5x/2x Charge Pump Modes
for a total of 120mA and allows several methods such as
a PWM signal on the CTRL0 pin for LED dimming. Three
Low Shutdown Current: 2µA Maximum
Low Input Ripple and EMI
control logic pins allow to disable or enable a combination of LEDs. The supply current is only 2mA in 2x mode,
Internal Soft-Start Limits Inrush Current
and the EN pin allows the device to enter shutdown mode
with 2µA quiescent current. The APW7000 switches at
Short Circuit Current Limit
Thermal Shutdown Protection
1MHz frequency and only requires four 1µF ceramic capacitors and one resistor, and ensures low input current
Output Over-Voltage Protection
ripple and EMI.
The APW7000 is available in a 16-pin QFN package.
16-Pin QFN Package
Lead Free and Green Devices Available
(RoHS Compliant)
Cellular Phone White LED Back Light
16 15
PDA, Handheld Computer
DSC
EN
1
CTRL0
2
CTRL1
3
CTRL2
4
ILED4
14 13
12 GND
11 C1-
Metal
GND Pad
(Bottom)
10 C1+
9
ISET
5
6
7
8
C2+
Portable Device
VIN
•
•
•
•
ILED1
Applications
ILED3
Pin Configuration
ILED2
•
•
•
•
•
•
•
•
•
•
•
•
ply voltage ranges from 2.7V to 5.5V and it is optimized for
a Li-ion battery application. The APW7000 operates in 1x,
VOUT
•
•
C2-
QFN4x4-16
(Top View)
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise
customers to obtain the latest version of relevant information to verify before placing orders.
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
1
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APW7000
Ordering and Marking Information
Package Code
QA : QFN4x4-16
Operating Ambient Temperature Range
I : -40 to 85 oC
Handling Code
TR : Tape & Reel
Assembly Material
G : Halogen and Lead Free Device
APW7000
Assembly Material
Handling Code
Temperature Range
Package Code
APW7000 QA :
APW7000
XXXXX
XXXXX - Date Code
Note: ANPEC lead-free products contain molding compounds/die attach materials and 100% matte tin plate termination finish; which
are fully compliant with RoHS. ANPEC lead-free products meet or exceed the lead-free requirements of IPC/JEDEC J-STD-020C for
MSL classification at lead-free peak reflow temperature. ANPEC defines “Green” to mean lead-free (RoHS compliant) and halogen
free (Br or Cl does not exceed 900ppm by weight in homogeneous material and total of Br and Cl does not exceed 1500ppm by
weight).
Absolute Maximum Ratings
Symbol
VOUT
VIN
VC1+, VC1-, VC2+, VC2VILED1-4
VCTRL0/1/2, VEN
VISET
TJ
(Note 1, 2)
Parameter
Rating
Unit
VOUT to GND
-0.3 to +6
V
VIN to GND
-0.3 to +6
V
C1+, C1-, C2+, C2- to GND
-0.3 to +6
V
ILED1-4 to GND
-0.3 to +6
V
CTRL0/1/2, EN to GND
-0.3 to +6
V
ISET to GND
-0.3 to 2
V
Maximum Junction Temperature
TSTG
Storage Temperature
TSDR
Maximum Lead Soldering Temperature, 10 Seconds
+150
°C
-65 ~ 150
°C
260
°C
Note 1: Stresses beyond the absolute maximum rating may damage the device and operating in the absolute maximum rating
conditions for extended periods may affect device reliability.
Note 2: The maximum allowable power dissipation at any TA (ambient temperature) is calculated using: PD(max) = (TJ – TA) / θJA ;TJ=125°C.
Exceeding the maximum allowable power dissipation will result in excessive die temperature.
Thermal Characteristics
Symbol
R θJA
Parameter
Thermal Resistance-Junction to Ambient
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
QFN4x4-16
2
Typical Value
Unit
40
°C/W
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APW7000
Recommended Operating Conditions
Symbol
VIN
Parameter
Unit
2.8 to 4.5
V
VOUT
Output Voltage
3 to 4
V
ILED
LED Current
5 to 30
mA
IOUT
TA
Input Voltage
Rating
Output Current, VIN>3.5V, VF=3.1V, 1x mode
180
Output Current, 3.5V<VIN>3.1V, VF=3.1V, 1.5x mode
120
Output Current, 3.1V<VIN>2.8V, VF=3.1V, 2x mode
90
Ambient Temperature
mA
°C
-40 to 85
Electrical Characteristics
VIN = 2.85 to 5.5V, CIN = COUT = C1 = C2 = 1µF (ESR = 0.03Ω), ILED = 20mA, T A = -40°C to +85°C, unless otherwise noted. Typical values
are at TA = +25°C.
Symbol
VIN
VUVLO
Parameter
Test Conditions
Input Voltage
Under-voltage Lockout Threshold
VIN falling
Under-voltage Lockout Hysteresis
IQ
ILED-ERR
IISET
VILED-TH
FOSC
ROUT
Quiescent Current
Unit
Min.
Typ.
Max.
2.7
-
5.5
2.2
2.4
2.6
V
-
50
-
mV
V
In 1.5x/2x mode
-
2
4
mA
No switching in 1x mode
-
0.5
1
mA
EN=0
-
0.1
2
µA
LED Current Accuracy
5mA<ILED<30mA
(Note 3)
-
±2
±8
%
Current Matching
5mA<ILED<30mA (Note 4)
-
±1.5
±5
%
5
-
1000
µA
370
400
420
ISET Current
ISET to LED Current Ratio
IILED / (1.2V / REST) 5mA<ILED<30mA,
TA = +25°C
ILED Threshold Voltage
VILED falling
-
100
-
mV
1.5x mode to 1x mode Transition
Hysteresis
VIN rising, VIN-VOUT
-
300
-
mV
2x mode to 1.5x mode Transition
Hysteresis
VIN rising, VOUT-VIN
-
300
-
mV
MHz
Switching Frequency
Open Loop VOUT Resistance
ISHORT
Short Circuit Current Limit
VOVP
OVP Threshold
0.8
1
1.2
1x mode (VIN-VOUT) / IOUT
-
1.6
3
1.5x mode (1.5xVIN-VOUT) / IOUT
-
7
12
2x mode (2xVIN-VOUT) / IOUT
-
16
28
VOUT < 1V
-
40
-
VIH
Logic Pins High Threshold
VIL
Logic Pins Low Threshold
IIH
Logic Pins High Current
VIH = VIN
Logic Pins Low Current
VIL = GND
IIL
APW7000
Ω
mA
5
5.5
6
1.3
0.7
-
-
0.6
0.3
V
-
-
1
µA
V
-
-
1
µA
Thermal Shutdown
-
150
-
°C
Thermal Shutdown Hysteresis
-
20
-
°C
Note 3: LED current accuracy is defined as: ± (ILED-MEASURED - ILED-SET) / ILED-SET
Note 4: LED current matching is defined as: ± (ILED-MAX - ILED-MIN) / (ILED-MAX + ILED-MIN)
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
3
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APW7000
Typical Operating Characteristics
Efficiency vs. Input Voltage
100
90
90
80
80
Efficiency (%)
Efficiency (%)
Efficiency vs. Input Voltage
100
70
60
4 LEDs at 20mA
VF=3.1V
50
70
60
50
40
40
30
30
20
4 LEDs at 15mA
VF=3.1V
20
2.5
3
3.5
4
4.5
2.5
3
Input Voltage (V)
100
90
90
80
80
Efficiency (%)
Efficiency (%)
Efficiency vs. Input Voltage
100
70
60
4 LEDs at 15mA
VF=3.3V
50
Efficiency vs. Input Voltage
60
4 LEDs at 20mA
VF=3.3V
50
40
30
30
20
2.5
3
3.5
4
4.5
2.5
3
Input Voltage (V)
3.5
4
Input Voltage (V)
4.5
Input Current vs. Input Voltage
Input Current vs. Input Voltage
200
260
240
180
4 LEDs at 30mA
Input Current (mA)
220
Input Current (mA)
4.5
70
40
20
3.5
4
Input Voltage (V)
200
180
160
140
4 LEDs at 20mA
160
140
120
100
80
120
100
60
2.5
3
3.5
4
4.5
5
2.5
Input Voltage (V)
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
3
3.5
4
4.5
5
Input Voltage (V)
4
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APW7000
Typical Operating Characteristics (Cont.)
LED Current vs. Input Voltage
LED Current vs. Input Voltage
32
21
31
LED Current (mA)
LED Current (mA)
20
19
4 LEDs at 20mA
18
30
29
4 LEDs at 30mA
28
27
17
26
16
25
2.5
3
3.5
4
4.5
5
5.5
2.5
3
3.5
Logic Threshold Voltage vs. Input Voltage
4.5
5
5.5
Switching Frequency vs. Input Voltage
1200
1.2
in 2x mode
ILED=20mA
1150
1.1
Switching Frequency (kHz)
Logic Threshold Voltage(V)
4
Input Voltage (V)
Input Voltage (V)
high threshold
1
0.9
low threshold
0.8
1100
1050
1000
950
900
850
800
0.7
2.5
1200
3
3.5
4
4.5
Input Voltage (V)
2.5
5.5
3
3.5
4
4.5
Input Voltage (V)
Switching Frequency vs. Temperature
LED Current vs. Temperature
21
4 LEDs at 20mA
VIN=4V
in 2x mode
VIN=4V
1100
1000
LED Current (mA)
Switching Frequency (kHz)
5
900
800
700
20
19
18
600
500
17
-40 -20
0
20
40
60
-40
80 100 120 140
Temperature (°C)
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
-20
0
20
40
60
80
100 120 140
Temperature (°C)
5
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APW7000
Typical Operating Characteristics (Cont.)
LED Current vs. Temperature
LED Current vs. Temperature
22
22
4 LEDs at 20mA
VIN=2.7V
4 LEDs at 20mA
VIN=3.3V
21
LED Current (mA)
LED Current (mA)
21
20
19
20
19
18
18
17
17
-40
-20
0
20
40
60
80
-40
100 120 140
-20
0
40
60
80
100 120 140
Temperature (°C)
Temperature (°C)
Quiescent Current vs. Temperature
Quiescent Current vs. Input Voltage
400
3
2.75
in 1x mode
VIN=4V
4 LEDs at 20mA
VF=3.3V
2.5
350
Quiescent Current (mA)
Quiescent Current (mA)
20
300
250
2.25
2
1.75
1.5
1.25
1
0.75
0.5
0.25
0
200
-40 -20
0
20
40
60
80
2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5
100 120 140
Temperature (°C)
Input Voltage(V)
StartUp in 1x Mode
IIN (100mA/div)
StartUp in 1.5x Mode
4 LEDs at 20mA
VF=3.1V, VIN=4V
IIN (100mA/div)
4 LEDs at 20mA
VF=3.1V, VIN=3.3V
VOUT (2V/div)
V OUT (2V/div)
EN (5V/div)
EN (5V/div)
ILED (10mA/div)
ILED (10mA/div)
TIME (0.1ms/div)
TIME (0.1ms/div)
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
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APW7000
Typical Operating Characteristics (Cont.)
StartUp in 2x Mode
Dimming in 1x Mode
ILED (10mA/div)
4 LEDs at 20mA
VF=3.1V, VIN=2.7V
IIN (100mA/div)
V OUT (2V/div)
VOUT (1V/div)
EN (5V/div)
4 LEDs at 20mA
VF=3.1V, VIN=4V
f=200Hz
CTRL0 (2V/div)
ILED (10mA/div)
TIME (0.1ms/div)
TIME (2ms/div)
Dimming in 1.5x Mode
Dimming in 2x Mode
ILED (10mA/div)
ILED (10mA/div)
V OUT (1V/div)
VOUT (1V/div)
CTRL0 (1V/div)
4 LEDs at 20mA, VF=3.1V
VIN=3.3V, f=200Hz
4 LEDs at 20mA, VF=3.1V,
VIN=2.7V, f=200Hz
CTRL0 (1V/div)
TIME (2ms/div)
TIME (2ms/div)
OVP Even with LED Open Circuit
Line Transient Response in 1x to 1.5x Mode
VIN (1V/div)
ILED (10mA/div)
4 LEDs at 20mA, VF=3.1V
VIN=3.2V to 3.8V
V OUT (1V/div)
VOUT (1V/div)
V IN (1V/div)
4 LEDs at 20mA
VF=3.1V, VIN=4V
LED1 is open
ILED (20mA/div)
TIME (0.1ms/div)
TIME (0.2ms/div)
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
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APW7000
Typical Operating Characteristics (Cont.)
Line Transient Response in 1.5x to 2x Mode
VIN (1V/div)
4 LEDs at 20mA, VF=3.1V
VIN=2.8V to 3.4V
VOUT (1V/div)
ILED (20mA/div)
TIME (0.1ms/div)
Pin Description
PIN
FUNCTION
NO.
NAME
1
EN
2
CTRL0
LED On/Off Control Pin. Allow disabling or enabling a combination of LEDs.
3
CTRL1
LED On/Off Control Pin. Allow disabling or enabling a combination of LEDs.
4
CTRL2
LED On/Off Control Pin. Allow disabling or enabling a combination of LEDs.
Enable Input Pin. The EN pin is an active high Control. Pull EN pin above 1.3V to enable the device; pull EN
pin below 0.3V to disable the device.
5
ISET
LED Current Set Input. Connect a resistor from ISET to GND to set the LED current. VISET is typically 1.2V.
6
VOUT
Output Voltage Pin. Connect VOUT to the LED anode. Connect a 1µF capacitor from VOUT to GND.
7
VIN
Supply Voltage Input Pin. Connect a 1µF capacitor from VIN to GND.
8
C2+
Bucket Capacitor1 Positive Terminal. Connect a 1µF capacitor from C2+ to C2-.
9
C2-
Bucket Capacitor1 Negative Terminal. Connect a 1µF capacitor from C2+ to C2-.
10
C1+
Bucket Capacitor1 Positive Terminal. Connect a 1µF capacitor from C1+ to C1-.
Bucket Capacitor1 Negative Terminal. Connect a 1µF capacitor from C1+ to C1-.
11
C1-
12
GND
Device Ground Pin.
13
ILED4
LEDs Cathode Connection. The LED current flows from VOUT through LED into ILED_ pin. The charge
pump regulates the lowest VILED to 180mV. Connect ILED_ pin to VOUT if the LED is not used.
14
ILED3
LEDs Cathode Connection. The LED current flows from VOUT through LED into ILED_ pin. The charge
pump regulates the lowest VILED to 180mV. Connect ILED_ pin to VOUT if the LED is not used.
15
ILED2
LEDs Cathode Connection. The LED current flows from VOUT through LED into ILED_ pin. The charge
pump regulates the lowest VILED to 180mV. Connect ILED_ pin to VOUT if the LED is not used.
16
ILED1
LEDs Cathode Connection. The LED current flows from VOUT through LED into ILED_ pin. The charge
pump regulates the lowest VILED to 180mV. Connect ILED_ pin to VOUT if the LED is not used.
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
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APW7000
Block Diagram
C1+
C2-
VOUT
1x/1.5x/2x MODE CHARGE PUMP AND
GATE CONTROL LOGIC
VIN
EN
C2+
C1-
POR &
SOFT-START
CURRENT LIMIT
CTRL1
LED ON/OFF
CONTROL
-
+
-
+
-
1MHz
OSCILLATOR
-
+
+
0.18V
CTRL0
0.1V
1.2V
MODE SELECT
AND
MIN ILED SELECT
CTRL2
ILED1
ILED2
CONTROLLED
CURRENT
MIRROR
ILED3
ILED4
+
-
Error
Amp
1.2V
+
+
+
+
-
-
-
-
ISET
GND
Typical Application Circuit
COUT
1µF
Digital
Inputs
16
15
14
13
ILED1 ILED2 ILED3 ILED4
EN
GND 12
1
2
3
4
CTRL0
C1- 11
APW7000
CTRL1
C1+ 10
CTRL2
ISET VOUT VIN
5
6
7
C2C2+
8
9
C2
1µF
C1
1µF
Battery
RSET
CIN
1µF
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
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APW7000
Function Description
where VF is the forward voltage of LED
Soft-Start
IOUT is the output current
ROUT1X is the output impedance in 1x mode = 1.6Ω
The APW7000 provides the soft-start function to limit the
inrush current during startup. When the input voltage is
supplied to the device and exceeds the UVLO voltage,
ROUT1.5X is the output impedance in 1.5x mode = 7Ω
the output capacitor is charged directly from input with a
limited current source. Approximate 100µs after the out-
Control Logic Pins
The APW7000 provides three logic input pins to enable
put voltage approaches the input voltage, the device starts
to provide the programmed LED current and determines
or disable a combination of LEDs. Table1 shows the truth
table of the logic pins. If the LED channels are not used,
which of 1x, and 1.5x, or 2x mode is required. When the
programmed LED current can be reached with 1x mode,
connecting the ILED pins to VOUT to turn off the respective LED channels.
the soft-start is completed and the device operates in 1x
mode. When the programmed LED current cannot be
Control Logic Pin
LED Status
CTRL2 CTRL1 CTRL0 LED4 LED3 LED2 LED1
0
0
0
OFF OFF OFF
ON
0
0
1
OFF OFF
ON
OFF
0
1
0
OFF
ON
OFF OFF
0
1
1
ON
OFF OFF OFF
1
0
0
OFF OFF
ON
ON
1
0
1
OFF
ON
ON
ON
1
1
0
ON
ON
ON
ON
1
1
1
OFF OFF OFF OFF
reached, the charge pump goes into 1.5x mode. If the
1.5x mode charge pump cannot suffice for the LED current need, the charge pump will switch to 2x mode.
Mode Transition
The APW7000 operates in 1x, 1.5x and 2x charge pump
modes and automatically switches the charge pump
modes depend on the input voltage to main tain the required power for high power efficiency. If the APW7000
Table1. The Truth Table of Control Logic Pins
operates in 1x mode, the VOUT is pulled up to VIN. When
VIN decreases, the VILED will decease to maintain the
LED Current Setting
regulated LED current. Until VILED is below 100mV, the
device will switch to 1.5x mode. In 1.5x mode, the VILED
Connect a resistor from ISET pin to GND to set the LED
current. The ISET voltage is typically 1.2V, and the LED
current is typically 400 times the current through the ISET
is regulated to 0.18V, and the output voltage is VF+0.18V.
If VIN continues to decrease until VILED is below 100mV
resistor. The LED current is given by:
again, the device will switch to 2x mode. When the VIN
rises and reaches by approximately VOUT-300mV, the
RSET =
400 × 1.2V
ILED
APW7000 switches back to 1.5x mode. If the VIN continues to rise and reaches by approximately VOUT+300mV,
The APW7000 provides up to 30mA of LED current per
the APW7000 switches back to 1x mode. The 2x charge
pump is enough to suffice the White LED for a Li-ion
LED and the device has a max current matching of ±5%
between any two LED currents and a max current accu-
battery application. The APW7000 ensures that in the 1x
mode for as long as possible to increase the efficiency
racy of ±8%. If high accuracy is required, using a 1% precision surface mount resistor for the need.
and extend the operating range by using the 2x mode.
The transition voltages from 1x to 1.5x and 1.5x to 2x are
ILED (mA)
5
10
15
20
30
given by:
VTRANS1X = VF + 0.1V + (IOUT x ROUT1X)
VTRANS1.5X = [VF + 0.1V + (IOUT x ROUT1.5X)] / 1.5
RSET (kΩ)
92
47
32
24
16.5
Table2. RSET Value Selection
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
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APW7000
Function Description (Cont.)
LED Current Setting (Cont.)
400
350
300
RSET (Ohm)
250
200
150
100
50
0
0
5
10
15
20
25
30
ILED (mA)
Figure 1. RSET Value vs. LED Current
Shutdown/Enable
Pull the EN above 1.3V to enable the device and pull EN
pin below 0.3V to disable the device. In shutdown mode,
all internal control circuits are turned off and the quiescent current is below 2µA. When the device exits shutdown mode, the output has soft-start function as the input voltage startup.
Over-Voltage Protection
If any of LEDs is failed or unused LED channel is not
connected to the VOUT, the charge pump mode will go
into 2x mode and the output voltage will be pumped to 2
times the input voltage. If the output voltage is over 5.5V,
the over-voltage protection circuit will limit the output voltage to approximately 5.5V.
Copyright  ANPEC Electronics Corp.
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APW7000
Application Information
20
For lower input and output voltage ripples, both input and
18
output capacitors should be larger values and lower ESR
capacitors. However, the larger output capacitor values
16
LED Current (mA)
Capacitor Selection
will increase the soft-start time. The lower charge pump
flying capacitors values and ESR improve the efficiency,
but lower capacitor values may limit the LED’s currents at
low input voltage.
LED=20mA
VIN=2.7V, 2x mode
14
f=100Hz
12
10
8
f=10kHz
6
It is recommended that the low ESR and low variation
over temperature, such as the ceramic capacitors with
4
X7R or X5R and the value is 1µF for the input capacitor,
output capacitor, and the charge pump flying capacitors.
0
f=40kHz
2
f=50kHz
0
10
20 30
40
50
60
70 80
90 100
Dimming Duty (%)
Brightness Control
Figure 3. PWM Dimming Frequency vs. LED Current
1. PWM dimming using CTRL0, CTRL1, CTRL2
The first method for dimming the LEDs is to apply a PWM
signal into the CTRL0, CTRL1, and CTRL2 pins. Figure2
2. Analog dimming with analog voltage
The second method for dimming the LEDs is to apply a
shows the application circuit. The average LED current is
proportional to the PWM signal duty cycle. Note that the
voltage through a resistor into the ISET pin. The variation
of LED current is proportional to the variation of the ana-
frequency of PWM signal will affect the minimum dimming duty. Figure3 shows the LED current vs. dimming
log voltage. If the resistor values are chosen correctly, the
analog control voltage varies the output current from 0mA
frequency and dimming duty, the recommend dimming
frequency is below 10kHz. The average LED current is
to full LED current. Figure 4 shows the application circuit.
See the table2 and choose the required maximum LED
current and the corresponsive RSET value, using the be-
calculated by the following equation:
ILED( avg) =
low equation to calculate the values of R1 and R2, note
that the VADJ will need to be greater than 1.2V.
toff × ILED(max)
ton + toff
VADJ ( VADJ − VISET ) VADJ
=
+
R1
R2
R SET
Where:
ILED(max) is programmed LED current by ISET pin
toff is the off time of the PWM signal
Where: VISET = 1.2V
VADJ = the analog voltage for dimming the LEDs
RSET = the equivalent RSET resistance (see table 2).
ton is the on time of the PWM signal
VIN
APW7000
ISET
APW7000
OFF
ON
PWM
1
2
3
4
R2
EN
5
VADJ
CTRL0
R1
CTRL1
CTRL2
Figure 4. Analog Voltage Dimming Application Circuit
Figure 2. PWM Dimming Application Circuit
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
12
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APW7000
Application Information (Cont.)
Brightness Control (Cont.)
Layout Consideration
3. Digital dimming with external NMOS transistors
The third method for dimming the LEDs is to change the
The APW7000 is a high frequency charge pump for white
LED driver and requires some care when laying out the
equivalent resistance for RSET with the external NMOS
transistors. The equivalent resistance is the parallel
printed circuit board. The metal GND pad of the bottom of
the package must be soldered to the PCB and connected
combinations of the R1, R2, R3, and R4. R4 is always
connected and selected for the minimum LED current.
to the GND plane on the backside through several thermal vias. Place the CIN, COUT, C1, and C2 as close to IC
Figure 5 shows the application circuit.
as possible for reducing the switching noise.
APW7000
ISET
5
R1
R2
R3
R4
Figure 5. Digital Dimming Application Circuit
4. PWM dimming with EN pin
Another method for dimming the LEDs is to apply a PWM
signal into the EN pin. The average LED current is proportional to the PWM signal duty cycle. Note that the frequency of PWM signal will affect the minimum dimming
duty. The recommend dimming frequency is between
100Hz and 1kHz. The average LED current is calculated
by the following equation:
ILED(avg ) =
ton × ILED(max)
ton + toff
Where:
ILED(max) is programmed LED current by ISET pin
toff is the off time of the PWM signal
ton is the on time of the PWM signal
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
13
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APW7000
Package Information
QFN4x4-16
D
b
E
A
Pin 1
A1
D2
A3
L K
E2
Pin 1 Corner
e
S
Y
M
B
O
L
QFN4x4-16
MILLIMETERS
INCHES
MIN.
MAX.
MIN.
MAX.
A
0.80
1.00
0.031
0.039
A1
0.00
0.05
0.000
0.002
0.35
0.010
0.014
0.161
A3
0.20 REF
0.008 REF
b
0.25
D
3.90
4.10
0.154
D2
2.10
2.50
0.083
0.098
0.161
0.098
E
3.90
4.10
0.154
E2
2.10
2.50
0.083
0.50
0.012
e
0.65 BSC
L
0.30
K
0.20
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
0.026 BSC
0.020
0.008
14
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APW7000
Carrier Tape & Reel Dimensions
P0
P2
P1
A
B0
W
F
E1
OD0
K0
A0
A
OD1 B
B
T
SECTION A-A
SECTION B-B
H
A
d
T1
Application
QFN4x4-16
A
H
T1
C
d
D
W
E1
F
330.0±2.00
50 MIN.
12.4+2.00
-0.00
13.0+0.50
-0.20
1.5 MIN.
20.2 MIN.
12.0±0.30
1.75±0.10
5.5±0.05
P0
P1
P2
D0
D1
T
A0
B0
K0
2.0±0.05
1.5+0.10
-0.00
1.5 MIN.
0.6+0.00
-0.40
4.30±0.20
4.30±0.20
1.30±0.20
4.0±0.10
8.0±0.10
(mm)
Devices Per Unit
Package Type
Unit
Quantity
QFN4x4-16
Tape & Reel
3000
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
15
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APW7000
Taping Direction Information
QFN4x4-16
USER DIRECTION OF FEED
Classification Profile
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
16
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APW7000
Classification Reflow Profiles
Profile Feature
Sn-Pb Eutectic Assembly
Pb-Free Assembly
100 °C
150 °C
60-120 seconds
150 °C
200 °C
60-120 seconds
3 °C/second max.
3°C/second max.
183 °C
60-150 seconds
217 °C
60-150 seconds
See Classification Temp in table 1
See Classification Temp in table 2
Time (tP)** within 5°C of the specified
classification temperature (Tc)
20** seconds
30** seconds
Average ramp-down rate (Tp to Tsmax)
6 °C/second max.
6 °C/second max.
6 minutes max.
8 minutes max.
Preheat & Soak
Temperature min (Tsmin)
Temperature max (Tsmax)
Time (Tsmin to Tsmax) (ts)
Average ramp-up rate
(Tsmax to TP)
Liquidous temperature (TL)
Time at liquidous (tL)
Peak package body Temperature
(Tp)*
Time 25°C to peak temperature
* Tolerance for peak profile Temperature (Tp) is defined as a supplier minimum and a user maximum.
** Tolerance for time at peak profile temperature (tp) is defined as a supplier minimum and a user maximum.
Table 1. SnPb Eutectic Process – Classification Temperatures (Tc)
Package
Thickness
<2.5 mm
≥2.5 mm
Volume mm
<350
235 °C
220 °C
3
Volume mm
≥350
220 °C
220 °C
3
Table 2. Pb-free Process – Classification Temperatures (Tc)
Package
Thickness
<1.6 mm
1.6 mm – 2.5 mm
≥2.5 mm
Volume mm
<350
260 °C
260 °C
250 °C
3
Volume mm
350-2000
260 °C
250 °C
245 °C
3
Volume mm
>2000
260 °C
245 °C
245 °C
3
Reliability Test Program
Test item
SOLDERABILITY
HOLT
PCT
TCT
ESD
Latch-Up
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
Method
JESD-22, B102
JESD-22, A108
JESD-22, A102
JESD-22, A104
MIL-STD-883-3015.7
JESD 78
17
Description
5 Sec, 245°C
1000 Hrs, Bias @ 125°C
168 Hrs, 100%RH, 2atm, 121°C
500 Cycles, -65°C~150°C
VHBM≧2KV, VMM≧200V
10ms, 1tr≧100mA
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APW7000
Customer Service
Anpec Electronics Corp.
Head Office :
No.6, Dusing 1st Road, SBIP,
Hsin-Chu, Taiwan, R.O.C.
Tel : 886-3-5642000
Fax : 886-3-5642050
Taipei Branch :
2F, No. 11, Lane 218, Sec 2 Jhongsing Rd.,
Sindian City, Taipei County 23146, Taiwan
Tel : 886-2-2910-3838
Fax : 886-2-2917-3838
Copyright  ANPEC Electronics Corp.
Rev. A.2 - Feb., 2009
18
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