Data Sheets - Skyworks Solutions, Inc.

DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
General Description
Features
The AAT3164 is a low noise, constant frequency charge
pump DC/DC converter that uses a tri-mode load switch
(1X), fractional (1.5X), and doubling (2X) conversion to
maximize efficiency for white LED applications. The
device is capable of driving up to six channels of LEDs at
up to 30mA per channel from a 2.7V to 5.5V input. The
current sinks may be operated individually or in parallel
for driving higher-current LEDs. A low external parts
count (two 1µF flying capacitors and two small 1µF
capacitors at IN and OUT) makes this part ideally suited
for small, battery-powered applications.
•VIN Range: 2.7V to 5.5V
• Tri-Mode (1X/1.5X/2X) Charge Pump Operation
▪ Maximizes Efficiency and LED VF Coverage
▪ 1MHz Constant Switching Frequency
▪ No Inductors, Low Noise Operation
• Drives Six Channels of LEDs up to 30mA/ Channel
▪ User-Programmable RSET Sets Maximum LED
Current
Excellent
LED Channel-to-Channel Current Match
▪
• Digitally Programmable LED Current with Single-Wire
S2Cwire Interface
▪ 16 Current Levels From ILED_MAX to 50µA
• Low IQ (70µA) for Low Current Mode Operation
• True Load Disconnect in Shutdown; IQ < 1µA
• Built-In Thermal Protection
• Built-In Auto-Disable for Open LED Circuit
•Automatic Soft-Start Minimizes Inrush Startup
Current
• Small 3x4mm TDFN34-16 Package
Skyworks' patented single-wire Simple Serial Control
(S2Cwire™) serial digital input is used to enable, disable,
and set current for each LED with 16 levels from a maximum of 40mA down to 50µA. The maximum current
level is programmed via an external resistor. To save
power, the low-current mode supply current can be programmed as low as 70µA.
Each output of the AAT3164 is equipped with built- in
protection for VOUT short-circuit and auto-disable for LED
short-circuit conditions. Built-in soft-start circuitry prevents excessive inrush current during start-up. A lowcurrent shutdown feature disconnects the load from VIN
and reduces quiescent current to less than 1µA.
Applications
• Color (RGB) Lighting
• Programmable Current Sinks
• White LED Backlighting
• White Photo Flash for Digital Still Cameras
The AAT3164 is available in a Pb-free, space-saving,
ultra-thin (3x4x0.75mm), thermally-enhanced 16-pin
TDFN package.
Typical Application
1µF
C1+
1µF
C1- C2+
IN
Li-Ion
Battery
VNOM = 3.6V
C2OUT
AAT3164
CIN
1µF
COUT
1µF
EN/SET
RSET
26.1K
1%
D2
D3
D4
D5
D6
OSRAM
LW M67C
GND
EN/SET
D1
D1
D2
D3
D4
D5
D6
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
1
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Pin Descriptions
Pin #
Symbol
1
2
3
4
5
6
D5
D6
RSET
EN/SET
C1+
C1-
7
OUT
8
9
10, 12
11
13
14
15
16
EP
C2+
C2GND
IN
D1
D2
D3
D4
Function
Current sink input #5.
Current sink input #6.
Connect resistor here to set maximum output current level. 1% resistor is recommended.
Enable Input or S2Cwire serial interface control.
Flying Capacitor 1 positive terminal. Connect a 1µF ceramic capacitor between C1+ and C1-.
Flying Capacitor 1 negative terminal.
Charge pump output to drive load circuit. Requires 1µF ceramic capacitor connected between this pin
and ground.
Flying Capacitor 2 positive terminal. Connect a 1µF ceramic capacitor between C2+ and C2-.
Flying Capacitor 2 negative terminal.
Ground.
Input power supply. Requires 1µF ceramic capacitor connected between this pin and ground.
Current sink input #1.
Current sink input #2.
Current sink input #3.
Current sink input #4.
Exposed paddle; connect to GND directly beneath the package.
Pin Configuration
TDFN34-16
(Top View)
D5
D6
RSET
EN/SET
C1+
C1OUT
C2+
2
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
D4
D3
D2
D1
GND
IN
GND
C2-
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Absolute Maximum Ratings1
Symbol
VIN
VEN/SET
IOUT2
TJ
TLEAD
Description
Input Voltage
EN/SET to GND Voltage
Maximum DC Output Current
Operating Junction Temperature Range
Maximum Soldering Temperature (at leads, 10 sec.)
Value
Units
-0.3 to 6
-0.3 to VIN + 0.3
300
-40 to 150
300
V
V
mA
°C
°C
Value
Units
2
50
W
°C/W
Thermal Information3
Symbol
PD
qJA
Description
Maximum Power Dissipation4
Maximum Thermal Resistance
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions
specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
2. Based on long-term current density limitation.
3. Mounted on an FR4 board.
4. Derate 20mW/°C above 25°C.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
3
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Electrical Characteristics1
CIN = COUT = C1 = C2 = 1µF; TA = -40°C to +85°C, unless otherwise noted. Typical values are TA = 25°C, VIN = 3.6V.
Symbol
Description
Conditions
Input Power Supply
VIN
Operation Range
ICC
Operating Current
ISHDN
Shutdown Current
IDX
ISINK Average Current
Accuracy
Current Matching2
1X to 1.5X or 1.5X to 2X
VTH
Transition Threshold at Any
ISINK Pin
ISET
Current Set Ratio
VRSET
RSET Pin Voltage
Charge Pump Section
TSS
Soft-Start Time
FCLK
Clock Frequency
EN/SET
VEN(L)
Enable Threshold Low
VEN(H)
Enable Threshold High
TEN/SET LO
EN/SET Low Time
TEN/SET HI(MIN) Minimum EN/SET High Time
TEN/SET HI(MAX) Maximum EN/SET High Time
TOFF
EN/SET Off Timeout
TLAT
EN/SET Latch Timeout
IEN/SET
EN/SET Input Leakage
Min
Typ
2.7
1X Mode, 3.0V ≤ VIN ≤ 5.5V, Active, No Load Current
1.5X Mode, 3.0V ≤ VIN ≤ 5.5V, Active, No Load Current
2X Mode, 3.0V ≤ VIN ≤ 5.5V, Active, No Load Current
50µA LED Current Setting, 1X Mode
EN/SET = 0
TA = -20°C to +85°C, RSET = 26.1kW, Data = 1 (100%)
TA = -40°C to +85°C, RSET = 26.1kW, Data = 1 (100%)
TA = -40°C to +85°C, RSET = 26.1kW, Data = 12 (14%)
TA = 25°C, Data = 14 (1mA)
0.3
1
1
70
-7
-8
-20
-10
I(D-Match)
±2
±2
0.5
ISINK/IRSET
Output Ramp Up Time
Max
Units
5.5
1
3
3
V
1
7
8
20
10
1
µA
µA
%
%
150
mV
870
0.6
A/A
V
100
1000
µs
kHz
0.4
1.4
0.3
75
50
VEN/SET = 5V
mA
-1
75
500
500
1
V
V
µs
ns
µs
µs
µs
µA
1. The AAT3164 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls.
2. Current matching is defined as the deviation of any sink current from the average of all active channels.
4
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Typical Characteristics
CIN = COUT = C1 = C2 = 1.0µF; TA = 25°C, RSET = 26.1kW, VIN = 3.6V, unless otherwise noted.
Efficiency vs. Supply Voltage
100
Efficiency (%)
90
5.0mA/ch
VF = 2.9V
10.2mA/ch
VF = 3.1V
Turn-On to 1X Mode
(VIN = 4.2V; 20mA/Channel; Data 1)
20mA/ch
VF = 3.4V
EN
(2V/div)
CP
(2V/div)
VSINK
(500mV/div)
80
70
60
IIN
(200mA/div)
50
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
Supply Voltage (V)
Time (100µs/div)
Turn-On to 1.5X Mode
Turn-On to 2X Mode
(VIN = 3.8V; 20mA/Channel; Data 1)
(VIN = 2.8V; 20mA/Channel; Data 1)
EN
(2V/div)
EN
(2V/div)
CP
(2V/div)
VSINK
(500mV/div)
CP
(2V/div)
VSINK
(500mV/div)
IIN
(200mA/div)
IIN
(200mA/div)
Time (100µs/div)
Time (100µs/div)
Current Matching vs. Temperature
Turn-Off from 1.5X Mode
(VIN = 3.5V; 20mA/Channel; Data 1)
20.2
EN
(2V/div)
Channel 1
Channel 2
Current (mA)
20.0
VF
(1V/div)
IIN
(100mA/div)
19.8
Channel 5
19.6
Channel 3
19.4
Channel 4
Channel 6
19.2
-40
Time (100µs/div)
-20
0
20
40
60
80
Temperature (°C)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
5
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Typical Characteristics
CIN = COUT = C1 = C2 = 1.0µF; TA = 25°C, RSET = 26.1kW, VIN = 3.6V, unless otherwise noted.
Load Characteristics
Load Characteristics
(VIN = 3.8V; 1.5X Mode; 14.2mA/Channel; Data 3)
(VIN = 2.9V; 2X Mode; 14.2mA/Channel; Data 3)
VIN
(40mV/div)
VIN
(40mV/div)
CP
(40mV/div)
CP
(40mV/div)
VSINK
(40mV/div)
VSINK
(40mV/div)
Time (500ns/div)
Time (500ns/div)
Load Characteristics
Load Characteristics
(VIN = 4.0V; 1.5X Mode; 20mA/Channel; Data 1)
(VIN = 3.1V; 2X Mode; 20mA/Channel; Data 1)
VIN
(40mV/div)
VIN
(40mV/div)
CP
(40mV/div)
CP
(40mV/div)
VSINK
(40mV/div)
VSINK
(40mV/div)
Time (500ns/div)
Time (500ns/div)
TLAT vs. VIN
TOFF vs. VIN
350
400
350
300
-40°C
-40°C
300
TOFF (µs)
TLAT (µs)
250
200
150
25°C
85°C
100
200
25°C
150
85°C
100
50
50
0
0
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
VIN (V)
6
250
VIN (V)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Typical Characteristics
CIN = COUT = C1 = C2 = 1.0µF; TA = 25°C, RSET = 26.1kW, VIN = 3.6V, unless otherwise noted.
Maximum LED Current vs. RSET
Input Ripple vs. VIN
20
40
18
35
16
Amplitude (mV)
45
ID (mA)
30
25
20
15
10
5
12
10
8
6
10.2mA/ch
4
2
0
0
10
15
20
25
30
35
40
45
50
55
60
65
70
75
2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2
RSET (kΩ)
VIN (V)
VIH vs. VIN
VIL vs. VIN
1.2
1.2
1.1
1.1
1
-40°C
1
0.9
0.9
0.8
0.8
0.7
25°C
0.6
85°C
VIL (V)
VIH (V)
20mA/ch
14
0.7
0.6
0.5
0.5
0.4
0.4
0.3
0.3
0.2
-40°C
25°C
85°C
0.2
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
VIN (V)
VIN (V)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
7
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Functional Block Diagram
C1+
C1- C2+
C2-
1x, 1.5x and 2x
Charge Pump
IN
OUT
Soft-Start
Control
1MHz
Oscillator
Voltage
Reference
EN/SET
S2Cwire
Interface
6 x 16 bit
ROM
D/A
D1
D/A
D2
D/A
D3
D/A
D4
D/A
D5
D/A
D6
Maximum
Current
Adjustment
GND
Functional Description
The AAT3164 is a tri-mode load switch (1X) and high
efficiency (1.5X or 2X) charge pump device intended for
white LED backlight applications. To maximize power
conversion efficiency, an internal sensing circuit monitors the voltage required on each constant current sink
input and sets the load switch and charge pump modes
based on the input battery voltage and the current sink
input voltage. As the battery discharges over time, the
AAT3164 charge pump is enabled when any of the six
current sink inputs near dropout. The charge pump initially starts in 1.5X mode. If the charge pump output
droops enough for any current sink input to become
close to dropout, the charge pump will automatically
transition to 2X mode. The AAT3164 requires only four
external components: two 1µF ceramic capacitors for the
charge pump flying capacitors (C1 and C2), one 1µF
8
RSET
ceramic input capacitor (CIN), and one 0.33µF to 1µF
ceramic charge pump output capacitor (COUT).
The S2Cwire serial interface enables the AAT3164 and
sets the current sink magnitudes. Since all current sinks
are truly independent constant current sinks, the voltage
observed on any single given input will be determined by
the actual forward voltage (VF) for the LED being driven.
Unused sink inputs must be connected to OUT, otherwise
the part will operate in 2X charge pump mode only.
Constant Current Output Level Settings
The current sink magnitude is controlled by Skyworks'
S2Cwire serial digital input. The maximum current is programmed by an external resistor at the RSET pin. Since
each current sink is programmable, no PWM (pulse width
modulation) or additional control circuitry is needed to
control LED brightness. This feature greatly reduces the
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
burden on a microcontroller or system IC to manage LED
or display brightness, allowing the user to “set it and
forget it.” With its high-speed serial interface (1MHz data
rate), the input sink current can be changed quickly and
easily. The code settings for the AAT3164 are listed in
Table 1.
Data
All Outputs D1~D6
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
100%
84%
71%
60%
51%
43%
35%
30%
25%
21%
17%
14%
1.8mA
1mA
530µA
50µA
The built-in S2Cwire interface records rising edges of the
EN/SET pin and decodes them into these current level
settings. S2Cwire latches data after the EN/SET pin has
been held high for time TLAT. A separate mode is available
for ultra-low LED current operation. This mode is enabled
by setting Data 13 to 16. While the AAT3164 is operating
in low current and 1X mode, the total quiescent current
is reduced to typically 70µA. When EN/SET is held low for
an amount of time longer than TOFF (500µs), the AAT3164
enters shutdown mode and draws less than 1µA from IN.
Data register is reset to 0 during shutdown.
Auto-Disable Feature
The AAT3164 is equipped with an auto-disable feature
for each LED channel. After the IC is enabled, a test current of 150µA (typical) is forced through each sink channel. The LED must develop a forward voltage of 0.8V for
the channel to turn on. This allows individual channels to
be disabled by connecting the respective sink pin to OUT.
This feature is convenient for disabling an unused channel or protecting against an LED fail short event.
Table 1: Current Level Settings as a Percentage
of the Maximum Level Set by RSET.
Thermal Protection
The AAT3164 has a built-in thermal protection circuit
that will shut down the charge pump if the die temperature rises above the thermal limit, as is the case during
a short-circuit of the OUT pin.
T HI
T LO
TOFF
TLAT
EN/SET
1
Data Reg
2
n-1
1
n ≤ 16
n
0
Figure 1: S2Cwire Serial Interface Timing Diagram.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
9
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Applications Information
Brightness Control Using the RSET Pin
LED Selection
Although the AAT3164 is specifically designed to drive
white LEDs, the device can also be used to drive most
types of LEDs with forward voltage specifications ranging
from 2.0V to 4.7V. LED applications may include LCD
display backlighting, camera photo-flash applications,
color (RGB) LEDs, infrared (IR) diodes for remotes, and
other loads benefiting from a controlled output current
generated from a varying input voltage. Since the D1 to
D6 input current sinks are matched with negligible voltage dependence, the LED brightness will be matched
regardless of the specific LED forward voltage (VF) levels.
In some instances (e.g., in high luminous output applications such as photo flash), it may be necessary to drive
high-VF type LEDs. The low dropout (~0.1V @ 20mA ILED)
current sinks in the AAT3164 make it capable of driving
LEDs with forward voltages as high as 4.7V from an
input supply as low as 3.0V. Outputs can be paralleled to
drive high-current LEDs without complication.
Determining the Maximum
LED Current Level
The value of RSET determines the maximum LED current
level. In the typical application, selecting RSET = 26.1kW
results in 20mA/channel LED current. From this reference point, the RSET value required for other current
levels can be calculated as:
RSET =
20mA · 26.1kΩ
ILED(MAX)
A visual representation of the maximum LED current per
Maximum
LEDisCurrent
vs.Figure
RSET 2.
channel versus
RSET value
shown in
45
40
35
Additional methods of brightness control can be achieved
with the RSET pin. For example, using an additional
resistor to connect the RSET pin with a digital output
provides a HI/LO control. Figure 3 illustrates a configuration of the RSET pin utilizing two resistors.
AAT3164
HI/LO
or
VDAC
R2
RSET
R1
Figure 3: RSET Configuration Using
Two Resistors.
When the digital output is asserted high, the resulting
brightness level is LO and the individual LED currents
are:
 0.6
VIO
ILED(LO) = 870  R // R - R 
1
2
2
When the digital output is asserted low, the resulting
brightness level is HI and the individual LED currents
are:
 0.6 
ILED(HI) = 870  R // R 
1
2
Additionally, a digital-to-analog converter can be used
with the RSET pin to control the brightness level. The
result is like the equation above, where VIO is replaced
with VDAC:
ID (mA)
30
25
 0.6
VDAC
ILED(LO) = 870  R // R - R 
1
2
2
20
15
10
5
0
10
15
20
25
30
35
40
45
50
55
60
65
70
75
RSET (kΩ)
Figure 2: Maximum LED Current vs. RSET.
10
For cases where PWM dimming is preferred, the PWM
signal can be applied directly to the RSET resistor, as
shown in Figure 4. In order for the LED current to go to
zero, the voltage level of the PWM signal must exceed
the RSET pin voltage level of 0.6V.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
to the LEDs. Further, the low resistance bypass switch
introduces negligible voltage drop from input to output.
AAT3164
PWM
R1
RSET
Figure 4: RSET Configuration for PWM Dimming
Control.
Device Power Efficiency
The AAT3164 power conversion efficiency depends on
the charge pump mode. By definition, device efficiency
is expressed as the output power delivered to the LEDs
divided by the total input power consumed.
η=
POUT
PIN
When the input voltage is sufficiently greater than the
LED forward voltages, the device optimizes efficiency by
operating in 1X mode. In 1X mode, the device is working
as a bypass switch and passing the input supply directly
to the output. By simplifying the conditions such that the
LEDs have uniform VF, the power conversion efficiency
can be approximated by:
η=
V
VF · ILED
≈ F
VIN · IIN
VIN
Due to the very low 1X mode quiescent current, the input
current nearly equals the total output current delivered
The AAT3164 further maintains optimized performance
and efficiency by detecting when the input voltage is not
sufficient to sustain LED drive current. The device automatically switches to 1.5X mode when the input voltage
drops too low in relation to the LED forward voltages.
In 1.5X mode, the output voltage can be boosted to 3/2
the input voltage. The 3/2 conversion ratio introduces a
corresponding 1/2 increase in input current. For ideal
conversion, the 1.5X mode efficiency is given by:
η=
VF
VF · ILED
≈
VIN · 1.5IIN 1.5 · VIN
Similarly, when the input falls further, such that 1.5X
mode can no longer sustain LED drive current, the
device will automatically switch to 2X mode. In 2X
mode, the output voltage can be boosted to twice the
input voltage. The doubling conversion ratio introduces
a corresponding doubling of the input current. For ideal
conversion, the 2X mode efficiency is given by:
η=
VF
VF · ILED
≈
VIN · 2IIN
2 · VIN
Additional Applications
The current sinks of the AAT3164 can be combined to
drive higher current levels through a single LED. As an
example, each LED of a three-die arrangement can be
driven at 80mA each, or 240mA total (see Figure 5).
Other applications that require constant current can also
be accommodated by combining constant current channels to achieve the necessary current levels.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
11
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
1µF
C1+
1µF
C1- C2+
IN
VBAT
C2OUT
3 LED pack
AAT3164
CIN
1µF
COUT
1µF
GND
EN/SET
EN/SET
RSET
D1
D2
D3
D4
D5
D6
80mA
each
26.1K
Figure 5: Configuration for a Typical Three-LED Application.
Device Switching Noise Performance
The AAT3164 operates at a fixed frequency of approximately 1MHz to control noise and limit harmonics that
can interfere with the RF operation of cellular telephone
handsets or other communication devices. Back-injected
noise appearing on the input pin of the charge pump is
20mV peak-to-peak, typically ten times less than inductor-based DC/DC boost converter white LED backlight
solutions. The AAT3164 soft-start feature prevents noise
transient effects associated with inrush currents during
start-up of the charge pump circuit.
Capacitor Selection
Careful selection of the four external capacitors CIN, C1,
C2, and COUT is important because they will affect turn-on
time, output ripple, and transient performance. Optimum
performance will be obtained when low Equivalent Series
Resistance (ESR) ceramic capacitors are used. In general, low ESR may be defined as less than 100mW. A
value of 1µF for all four capacitors is a good starting
point when choosing capacitors. If the LED current
sources are only programmed for light current levels,
then the capacitor value may be decreased.
polarized. Low ESR ceramic capacitors help maximize
charge pump transient response. Since ceramic capacitors are non-polarized, they are not prone to incorrect
connection damage.
Equivalent Series Resistance
ESR is an important characteristic to consider when
selecting a capacitor. ESR is a resistance internal to a
capacitor that is caused by the leads, internal connections, size or area, material composition, and ambient
temperature. Capacitor ESR is typically measured in milliohms for ceramic capacitors and can range to more
than several ohms for tantalum or aluminum electrolytic
capacitors.
Ceramic Capacitor Materials
Capacitor Characteristics
Ceramic capacitors less than 0.1µF are typically made
from NPO or C0G materials. NPO and C0G materials generally have tight tolerance and are very stable over temperature. Larger capacitor values are usually composed
of X7R, X5R, Z5U, or Y5V dielectric materials. Large
ceramic capacitors (i.e., greater than 2.2µF) are often
available in low-cost Y5V and Z5U dielectrics, but capacitors greater than 1µF are not typically required for
AAT3164 applications.
Ceramic composition capacitors are highly recommended
over all other types of capacitors for use with the
AAT3164. Ceramic capacitors offer many advantages
over their tantalum and aluminum electrolytic counterparts. A ceramic capacitor typically has very low ESR, is
lowest cost, has a smaller PCB footprint, and is non-
Capacitor area is another contributor to ESR. Capacitors
that are physically large will have a lower ESR when
compared to an equivalent material smaller capacitor.
These larger devices can improve circuit transient
response when compared to an equal value capacitor in
a smaller package size.
12
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
DATA SHEET
AAT3164
AAT3164 High Efficiency 1x/1.5x/2x Charge Pump
for Six-Channel White LED Applications
Ordering Information
Package
Marking1
Part Number (Tape and Reel)2
TDFN34-16
QBXYY
AAT3164IRN-T1
Skyworks Green™ products are compliant with
all applicable legislation and are halogen-free.
For additional information, refer to Skyworks
Definition of Green™, document number
SQ04-0074.
Package Information
TDFN34-16
1.600 ± 0.050
0.35 REF
0.25 REF
1.600 ± 0.050
0.750 ± 0.050
Top View
0
+ 0.100
-0.000
All dimensions in millimeters.
R0.15 (REF)
Pin 1 ID
0.450 ± 0.050
0.230 ± 0.050
4.000 ± 0.050
Index Area
2.350 ± 0.050
0.700 ± 0.050
3.000 ± 0.050
0.430 ± 0.050
Bottom View
0.230 ± 0.050
Side View
1. XYY = assembly and date code.
2. Sample stock is generally held on part numbers listed in BOLD.
Copyright © 2012 Skyworks Solutions, Inc. All Rights Reserved.
Information in this document is provided in connection with Skyworks Solutions, Inc. (“Skyworks”) products or services. These materials, including the information contained herein, are provided by Skyworks as a
service to its customers and may be used for informational purposes only by the customer. Skyworks assumes no responsibility for errors or omissions in these materials or the information contained herein. Skyworks may change its documentation, products, services, specifications or product descriptions at any time, without notice. Skyworks makes no commitment to update the materials or information and shall have no
responsibility whatsoever for conflicts, incompatibilities, or other difficulties arising from any future changes.
No license, whether express, implied, by estoppel or otherwise, is granted to any intellectual property rights by this document. Skyworks assumes no liability for any materials, products or information provided hereunder, including the sale, distribution, reproduction or use of Skyworks products, information or materials, except as may be provided in Skyworks Terms and Conditions of Sale.
THE MATERIALS, PRODUCTS AND INFORMATION ARE PROVIDED “AS IS” WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, INCLUDING FITNESS FOR A PARTICULAR
PURPOSE OR USE, MERCHANTABILITY, PERFORMANCE, QUALITY OR NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHT; ALL SUCH WARRANTIES ARE HEREBY EXPRESSLY DISCLAIMED. SKYWORKS DOES
NOT WARRANT THE ACCURACY OR COMPLETENESS OF THE INFORMATION, TEXT, GRAPHICS OR OTHER ITEMS CONTAINED WITHIN THESE MATERIALS. SKYWORKS SHALL NOT BE LIABLE FOR ANY DAMAGES, INCLUDING BUT NOT LIMITED TO ANY SPECIAL, INDIRECT, INCIDENTAL, STATUTORY, OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUES OR LOST PROFITS THAT MAY RESULT FROM
THE USE OF THE MATERIALS OR INFORMATION, WHETHER OR NOT THE RECIPIENT OF MATERIALS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Skyworks products are not intended for use in medical, lifesaving or life-sustaining applications, or other equipment in which the failure of the Skyworks products could lead to personal injury, death, physical or environmental damage. Skyworks customers using or selling Skyworks products for use in such applications do so at their own risk and agree to fully indemnify Skyworks for any damages resulting from such improper
use or sale.
Customers are responsible for their products and applications using Skyworks products, which may deviate from published specifications as a result of design defects, errors, or operation of products outside of published parameters or design specifications. Customers should include design and operating safeguards to minimize these and other risks. Skyworks assumes no liability for applications assistance, customer product
design, or damage to any equipment resulting from the use of Skyworks products outside of stated published specifications or parameters.
Skyworks, the Skyworks symbol, and “Breakthrough Simplicity” are trademarks or registered trademarks of Skyworks Solutions, Inc., in the United States and other countries. Third-party brands and names are for
identification purposes only, and are the property of their respective owners. Additional information, including relevant terms and conditions, posted at www.skyworksinc.com, are incorporated by reference.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
13