Anpec APW7001QAI-TRG 1x/1.5x/2x charge pump white led driver for main and sub-display Datasheet

APW7001
1X/1.5X/2X Charge Pump White LED Driver for Main and Sub-Displays
Features
General Description
•
•
•
The APW7001 is a high efficiency charge pump white
LED driver; the device drives up to four white LEDs in the
±1.5% LED Current Matching
Powers Main and Sub-Display LEDs
main display and up to two white LEDs in the sub-display
with regulated constant current for uniform intensity. The
High Efficiency Up to 90% Over Li-ion Battery
supply voltage ranges from 2.7V to 5.5V and it is optimized for a Li-ion battery application. The APW7001 op-
Discharge
Output Current Up to 30mA per LED
erates in 1x, 1.5x, and 2x charge pump modes and automatically switches the charge pump modes depend on
2.7V to 5.5V Operating Voltage
the input voltage to maintain the required power for high
power efficiency. The APW7001 provides up to 30mA per
1x/1.5x/2x Charge Pump Modes
Low Shutdown Current: 2µA Maximum
LED and allows several methods such as the PWM signals on the ENM pin for main-display dimming and on
Low Input Ripple and EMI
the ENS pin for sub-display dimming. The two control
logic pins, ENM and ENS, allow disabling or enabling the
Internal Soft-Start Limits Inrush Current
Short Circuit Current Limit
main and sub-displays. The supply current is only 2mA in
2x mode, and the ENM and ENS are kept low for 20ms
Thermal Shutdown Protection
will allow the device to enter shutdown mode with 2µA
quiescent current. The APW7001 features current limit
Output Over-Voltage Protection
16-pin QFN Package
and short circuit protection. The APW7001 switches at
1MHz frequency and only requires four 1µF ceramic ca-
Lead Free and Green Devices Available
(RoHS Compliant)
pacitors and one resistor, and ensures low input current
ripple and EMI. The APW7001 is available in a 16-pin
QFN package.
Applications
PDA, Handheld Computer
ILED 1
ILED 2
Portable Device
ILED 3
Pin Configuration
Cellular Phone White LED Back Light
ILED 4
16 15 14 13
1
ILED 6
2
ENM
3
ENS
4
12 GND
Metal
GND Pad
(Bottem)
11 C110 C1+
9
5
6
7
8
C2+
ILED 5
VIN
DSC
VOUT
•
•
•
•
ISET
•
•
•
•
•
•
•
•
•
•
•
C2-
APW7001
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.4 - Oct., 2009
1
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APW7001
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
APW7001
Assembly Material
Handling Code
Temperature Range
Package Code
APW7001 QA :
APW7001
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-020D 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
(Note 1)
Rating
Unit
VOUT to GND
Parameter
-0.3 to +6
V
VIN to GND
-0.3 to +6
V
-0.3 to +6
V
-0.3 to +6
V
-0.3 to +6
V
-0.3 to 2
V
VC1+, VC1-,
C1+, C1-, C2+, C2- to GND
VC2+, VC2VILED1-6
ILED1-6 to GND
VENM, VENS ENM, ENS to GND
VISET
TJ
ISET to GND
Maximum Junction Temperature
TSTG
Storage Temperature
TSDR
Maximum Lead Soldering Temperature, 10 Seconds
+150
°C
-65 ~ 150
°C
260
°C
Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
Thermal Characteristics (Note 2)
Symbol
θJA
Parameter
Thermal Resistance -Junction to Ambient
QFN4x4-16
Typical Value
Unit
40
°C/W
Note 2 : θJA is measured with the component mounted on a high effective thermal conductivity test board in free air.
Recommended Operating Conditions
Symbol
VIN
Parameter
Input Voltage
Rating
Unit
2.8 to 4.5
V
VOUT
Output Voltage
3 to 4
V
ILED
LED Current
5 to 30
mA
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
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APW7001
Recommended Operating Conditions (Cont.)
Symbol
IOUT
Parameter
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
TA
Unit
mA
90
Ambient Temperature
°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
Quiescent Current
LED Current Accuracy
Current Matching
IISET
VILED-TH
FOSC
ROUT
APW7001
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
5mA<ILED<30mA (Note 3)
-
±2
±8
%
5mA<ILED<30mA
(Note 4)
ISET Current
-
±1.5
±5
%
5
-
1000
µA
370
400
420
ISET to LED Current Ratio
ILED / (1.2V/RSET)
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
Output Over Voltage Protection
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
Ω
-
40
-
mA
5
5.5
6
V
VIH
Logic Pins High Threshold
1.3
0.7
-
V
VIL
Logic Pins Low Threshold
-
0.6
0.3
V
IIH
Logic Pins High Current
VIH=VIN
-
-
1
µA
IIL
Logic Pins Low Current
VIL=GND
-
-
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.4 - Oct., 2009
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APW7001
Typical Operating Characteristics
Efficiency vs. Input Voltage
100
90
90
80
80
70
70
Efficiency (%)
Efficiency (%)
Efficiency vs. Input Voltage
100
60
6 LEDs at 20mA
VF=3.1V
50
60
40
40
30
30
20
6 LEDs at 15mA
VF=3.1V
50
20
2.5
3
3.5
4
4.5
2.5
3
Input Voltage (V)
4.5
Efficiency vs. Input Voltage
100
100
90
90
80
80
Efficiency (%)
Efficiency (%)
4
Input Voltage (V)
Efficiency vs. Input Voltage
70
60
6 LEDs at 20mA
VF=3.3V
50
3.5
70
60
6 LEDs at 15mA
VF=3.3V
50
40
40
30
30
20
20
2.5
3
3.5
Input Voltage (V)
4
2.5
4.5
3
3.5
4
4.5
Input Voltage (V)
Input Current vs. Input Voltage
Input Current vs. Input Voltage
300
200
6 LEDs at 20mA
175
6 LEDs at 15mA
Input Current (mA)
Input Current (mA)
250
200
150
150
125
100
75
50
100
2.5
3
3.5
4
4.5
2.5
5
Input Voltage (V)
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Rev. A.4 - Oct., 2009
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3.5
4
4.5
5
Input Voltage (V)
4
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APW7001
Typical Operating Characteristics (Cont.)
LED Current vs. Input Voltage
LED Current (mA)
LED Current (mA)
20
19
18
16
15
14
17
13
16
12
2.5
3
3.5
4
4.5
Input Voltage (V)
5
2.5
5.5
3
3.5
4
4.5
5
5.5
Input Voltage (V)
LED Current vs. Temperature
21
6 LEDs at 15mA
17
6 LEDs at 20mA
21
LED Current vs. Input Voltage
18
22
LED Current vs. Temperature
22
6 LEDs at 20mA
VIN=3.3V, 1.5x mode
6 LEDs at 20mA
VIN=4V, 1x mode
21
LED Current (mA)
LED Current (mA)
20
19
18
20
19
18
17
17
-40
-20
0
20
40
60
80
-40
100 120 140
-20
0
20
Temperature (°C)
LED Current vs. Temperature
60
80
100 120 140
Quiescent Current vs. Input Voltage
22
3
6 LEDs at 20mA
VIN=3V, 2x mode
6 LEDs at 15mA
VF=3.3V
2.5
Quiescent Current (mA)
21
LED Current (mA)
40
Temperature (°C)
20
19
18
2
1.5
1
0.5
0
2.5
17
-40
-20
0
20
40
60
80
100 120 140
Temperature (°C)
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
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3.5
4
4.5
Input Voltage(V)
5
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APW7001
Typical Operating Characteristics (Cont.)
Quiescent Current vs. Temperature
Logic Threshold Voltage vs. Input Voltage
700
1.2
in 1x mode
VIN=4V
Logic Threshold Voltage (V)
Quiescent Current (mA)
600
500
400
300
1.1
high threshold
1
0.9
low threshold
0.8
0.7
200
-40 -20
0
20
40
60
80
2.5
100 120 140
3
3.5
4
4.5
Input Voltage (V)
Temperature (°C)
Switching Frequency vs. Input Voltage
5.5
Switching Frequency vs. Temperature
1200
1200
in 2x mode
VIN=4V
in 2x mode
1150
1100
Switching Frequency (kHz)
Switching Frequency (kHz)
5
1100
1050
1000
950
900
1000
900
800
700
600
850
500
800
2.5
3
3.5
4
-40 -20
4.5
Input Voltage (V)
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
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20
40
60
80 100 120 140
Temperature (°C)
6
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APW7001
Typical Operating Characteristics (Cont.)
Start Up in 1.5x Mode
Start Up in 1x Mode
6 LEDs at 20mA
V F=3.1V, VIN =4V
IIN (100mA/div)
6 LEDs at 20mA
VF=3.1V, VIN=3.3V
IIN (200mA/div)
V OUT (2V/div)
VOUT (2V/div)
ENS=ENM (5V/div)
ENS=ENM (5V/div)
ILED (20mA/div)
ILED (20mA/div)
TIME (0.1ms/div)
TIME (0.1ms/div)
Start Up in 2x Mode
Dimming in 1x Mode
ILED (20mA/div)
IIN (200mA/div)
6 LEDs at 20mA
VF =3.1V, VIN =2.7V
6 LEDs at 20mA, VF =3.1V,
VOUT (1V/div)
VIN =4V f=200Hz, ENS=high
VOUT (2V/div)
ENM (2V/div)
ENS=ENM (5V/div)
ILED (20mA/div)
TIME (0.1ms/div)
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
TIME (2ms/div)
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APW7001
Typical Operating Characteristics (Cont.)
Dimming in 2x Mode
Dimming in 1.5x Mode
ILED (20mA/div)
ILED (20mA/div)
6 LEDs at 20mA, VF =3.1V,
6 LEDs at 20mA, VF=3.1V,
VOUT (1V/div)
VIN=3.3V, f=200Hz, ENS=high
VIN =2.7V, f=200Hz, ENS=high
VOUT (1V/div)
ENM (1V/div)
ENM (1V/div)
TIME (2ms/div)
TIME (2ms/div)
OVP Even with LED Open Circuit
Line Transient Response in 1x to 1.5x Mode
6 LEDs at 20mA, V F =3.1V
VIN =3.2V to 3.8V
ILED (10mA/div)
VIN (1V/div)
VOUT (1V/div)
VOUT (1V/div)
V IN (1V/div)
6 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.4 - Oct., 2009
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APW7001
Typical Operating Characteristics (Cont.)
Line Transient Response in 1.5x to 2x Mode
6 LEDs at 20mA, VF =3.1V
V IN =2.8V to 3.4V
VIN (1V/div)
VOUT (1V/div)
ILED (20mA/div)
TIME (0.1ms/div)
Pin Description
PIN
FUNCTION
NO.
NAME
1
ILED5
2
ILED6
3
ENM
On/Off and Dimming Control for LED1-4 (Main-Display).
4
ENS
On/Off and Dimming Control for LED5-6 (Sub-Display).
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 anodes. 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-.
11
C1-
Bucket Capacitor1 Negative Terminal. Connect a 1µF capacitor from C1+ to C1-.
12
GND
13
ILED1
14
ILED2
15
ILED3
16
ILED4
Sub-Display 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.
Device Ground Pin.
Main-Display 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.
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APW7001
Block Diagram
C1+
C2+
C1-
C2-
VOUT
1x/1.5x/2x MODE CHARGE PUMP AND
GATE CONTROL LOGIC
VIN
POR &
SOFT-START
CURRENT
LIMIT
-
+
-
-
+
-
+
+
ENM
SUB CONTROL
ENS
MAIN CONTROL
0.18V
1MHz
OSCILLATOR
0.1V
1.2V
MODE SELECT
AND
MIN ILED SELECT
CONTROLLED
CURRENT
MIRROR
ILED1
ILED2
+
1.2V
ILED3
-
Error
Amp
ISET
ILED4
ILED5
ILED6
+
+
+
+
+
+
-
-
-
-
-
-
GND
Typical Application Circuit
COUT
1µF
16
15
14
13
ILED4 ILED3 ILED2 ILED1
ILED5
GND 12
1
2
3
Digital
Inputs
4
ILED6
C1- 11
APW7001
ENM
C1+ 10
ENS
ISET VOUT VIN
5
C2
1µF
6
7
C29
C2+
8
C1
1µF
Battery
RSET
CIN
1µF
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Rev. A.4 - Oct., 2009
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APW7001
Function Description
Soft-Start
The APW7001 provides the soft-start function to limit the
VF is the forward voltage of LED
IOUT is the output current
inrush current during startup. When the input voltage is
supplied to the device and exceeds the UVLO voltage, the
ROUT1X is the output impedance in 1x mode = 1.6Ω
ROUT1.5X is the output impedance in 1.5x mode = 7Ω
output capacitor is charged directly from input with a limited current source. Approximate 100µs after the output
ENM/ENS Control Logic Pins
The APW7001 provides two logic input pins to enable or
disable the main-display and sub-display. When the ENM
voltage approaches the input voltage, the device starts to
provide the programmed LED current and determines
or ENS is high, the VOUT is supplied and the respective
LEDs are enabled. When ENM or ENS is low, the respec-
which of 1x, and 1.5x, or 2x mode is required. When the
programmed LED current can be reached with 1x mode,
tive LEDs are disabled. If both logic pins are kept low for
more than 20ms, the APW7001 enters shutdown mode.
the soft-start is completed and the device operates in 1x
mode. When the programmed LED current cannot be
In shutdown mode, all internal control circuits are turned
off and the quiescent current is below 2µA. When the
reached, the charge pump goes into 1.5x mode. If the
1.5x mode charge pump cannot suffice for the LED cur-
device exits shutdown mode, the output has the soft-start
function as the input voltage startup.
rent need, the charge pump will switch to 2x mode.
Mode Transition
The APW7001 operates in 1x, 1.5x, and 2x charge pump
modes and automatically switches the charge pump
modes depend on the input voltage to maintain the required power for high power efficiency. If the APW7001
operates in 1x mode, the VOUT is pulled up to VIN. When
VIN decreases, the VILED will decease to maintain the regulated LED current. Until VILED is below 100mV, the device
ENM
ENS
0 (for more
than 20ms)
0 (for more
than 20ms)
1
0
0
1
1
1
LED Status
IC enters shutdown
LED1, 2, 3, 4 are turned on /
LED5, 6 are turned off
LED1, 2, 3, 4 are turned off /
LED5, 6 are turned on
LED1, 2, 3, 4 are turned on /
LED5, 6 are turned on
Table 1. The Truth Table of ENM and ENS
will switch to 1.5x mode. In 1.5x mode, the VILED is regulated to 0.18V, and the output voltage is VF+0.18V. If VIN
LED Current Setting
Connect a resistor from ISET pin to GND to set the LED
continues to decrease until VILED is below 100mV again,
the device will switch to 2x mode. When the VIN rises and
current. The ISET voltage is 1.2V, and the LED current is
typically 400 times the current through the ISET resistor.
reaches by approximately VOUT-300mV, the APW7001
switches back to 1.5x mode. If the VIN continues to rise
The LED current is given by:
and reaches by approximately VOUT+300mV, the
APW7001 switches back to 1x mode. The 2x charge pump
RSET =
is enough to suffice the White LED for a Li-ion battery
application. The APW7001 ensures that in the 1x mode
400 × 1.2V
ILED
The APW7001 provides up to 30mA of LED current per
LED and the device has a max current matching of ±5%
between any two LED currents and a max current accu-
for as long as possible to increase the efficiency and
extend the operating range by using the 2x mode. The
racy of ±8%. If high accuracy is required, using a 1% precision surface mount resistor for the need.
transition voltages from 1x to 1.5x, and 1.5x to 2x are given
by:
ILED (mA)
5
10
15
20
30
VTRANS1X = VF + 0.1V + (IOUT x ROUT1X)
VTRANS1.5X = [VF + 0.1V + (IOUT x ROUT1.5X)] / 1.5
where
RSET (kΩ)
92
47
32
24
16.5
Table 2. RSET Value Selection
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APW7001
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
Over-Voltage Protection
If any of LEDs is failed or unused, LED channel is not
connected to 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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APW7001
Application Information
Capacitor Selection
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
will increase the soft-start time. The lower charge pump
flying capacitors values and ESR improve the efficiency,
12
LED=20mA
in 2x mode
LED Current (mA)
14
but lower capacitor values may limit the LED’s currents at
low input voltage.
It is recommended that the low ESR and low variation
over temperature, such as the ceramic capacitors with
f=100Hz
10
8
f=10kHz
6
f=40kHz
4
2
X7R or X5R and the value is 1µF for the input capacitor,
output capacitor, and the charge pump flying capacitors.
f=50kHz
0
0
10
20
30
Brightness Control
70
80
90
100
ENM
tional to the PWM signal duty cycle. Note that the frequency
of PWM signal will affect the minimum dimming duty.
ILED
(main)
Figure 3 shows the LED current vs. dimming frequency
and dimming duty, the recommend dimming frequency
Bright ness
(main)
100%
25%
is below 10kHz. The PWM signal can either be applied to
ENM or ENS, or both inputs can be tied together and the
ENS
PWM signal can be applied to both pins. Table 3 shows
the truth table of ENM and ENS dimming control. The
ILED
(sub)
Bright ness
(sub)
average LED current is calculated by the following
equation:
100%
75%
50%
20ms
ton × ILED(max)
ton + toff
Shutdown
Figure 4. ENM/ENS Timing
Where:
ILED(max) is programmed LED current by ISET pin
ENM
toff is the off time of the PWM signal
ton is the on time of the PWM signal
ON
APW7001
OFF
3
ENM
ON
OFF
PWM
60
VOUT
signal into the ENM or/and ENS pins. Figure 2 shows the
application circuit. The average LED current is propor-
PWM
50
Figure 3. PWM Dimming Frequency vs. LED Current
1. PWM dimming using ENM, or/and EMS
The first method for dimming the LEDs is to apply a PWM
ILED(avg ) =
40
Dimming Duty (%)
4
ENS
0
PWM
PWM
0
1
PWM
PWM
1
PWM
PWM
LED Status
LED1, 2, 3, 4 are turned off
LED5, 6 are PWM dimming
LED1, 2, 3, 4 are PWM dimming
LED5, 6 are turned off
LED1, 2, 3, 4 are turned on
LED5, 6 are PWM dimming
LED1, 2, 3, 4 are PWM dimming
LED5, 6 are turned on
LED1, 2, 3, 4 are PWM dimming
LED5, 6 are PWM dimming
Table 3. The Truth Table of ENM and
ENS
ENS Dimming Control
Figure 2. PWM Dimming Application Circuit
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
13
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APW7001
Application Information (Cont.)
Brightness Control (Cont.)
4. PWM dimming with EN pin
Another method for dimming the LEDs is to apply a PWM
2. Analog Dimming With Analog Voltage
signal into the EN pin. The average LED current is proportional to the PWM signal duty cycle. Note that the fre-
The second method for dimming the LEDs is to apply a
voltage through a resistor into the ISET pin. The variation
quency of PWM signal will affect the minimum dimming
duty. The recommend dimming frequency is between
of LED current is proportional to the variation of the analog voltage. If the resistor values are chosen correctly, the
100Hz and 1kHz. The average LED current is calculated
by the following equation:
analog control voltage varies the output current from 0mA
to full LED current. Figure 5 shows the application circuit,
and the LED current is calculated by the following
equation:
I
=
ton × ILED(max)
ton + toff
Where:
ILED(max) is programmed LED current by ISET pin
 1.2V − VADJ 1.2V 
ILED = 400 × 
+

R2
R1 

toff is the off time of the PWM signal
ton is the on time of the PWM signal
APW7001
ISET
R2
LED(avg)
Layout Consideration
5
The APW7001 is a high frequency charge pump for white
LED driver and requires some care when laying out the
VADJ
R1
printed circuit board. The metal GND pad of the bottom of
the package must be soldered to the PCB and connected
to the GND plane on the backside through several ther-
Figure 5. Analog Voltage Dimming Application Circuit
mal vias. Place the CIN, COUT, C1, and C2 as close to IC
as possible for reducing the switching noise.
3. Digital dimming with external NMOS transistors
The third method for dimming the LEDs is to change the
equivalent resistance for RSET with the external NMOS
transistors. The equivalent resistance is the parallel combinations of the R1, R2, R3, and R4. R4 is always connected and selected for the minimum LED current. Figure 6 shows the application circuit.
APW7001
ISET
5
R1
R2
R3
R4
Figure 6. Digital Dimming Application Circuit
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
14
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APW7001
Package Information
QFN4x4-16
D
b
E
A
Pin 1
D2
A1
A3
L
K
E2
Pin 1 Corner
e
S
Y
M
B
O
L
A
A1
QFN4x4-16
MILLIMETERS
INCHES
MIN.
MAX.
MIN.
MAX.
0.80
1.00
0.031
0.039
0.05
0.000
0.002
0.00
A3
0.20 REF
0.008 REF
b
0.25
0.35
0.010
0.014
D
3.90
4.10
0.154
0.161
D2
2.50
2.80
0.098
0.110
0.161
0.110
E
3.90
4.10
0.154
E2
2.50
2.80
0.098
e
0.65 BSC
L
0.30
K
0.20
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
0.026 BSC
0.012
0.50
0.020
0.008
15
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APW7001
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
4.0±0.10
8.0±0.10
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
(mm)
Devices Per Unit
Package Type
Unit
Quantity
QFN4x4-16
Tape & Reel
3000
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
16
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APW7001
Taping Direction Information
QFN4x4-16
USER DIRECTION OF FEED
Classification Profile
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
17
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APW7001
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
HBM
MM
Latch-Up
Method
JESD-22, B102
JESD-22, A108
JESD-22, A102
JESD-22, A104
MIL-STD-883-3015.7
JESD-22, A115
JESD 78
Copyright  ANPEC Electronics Corp.
Rev. A.4 - Oct., 2009
18
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
www.anpec.com.tw
APW7001
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.4 - Oct., 2009
19
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