AAT AAT3129ITP-60-T1 High efficiency 1x/1.5x/2x charge pump for rgb color led application Datasheet

AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
General Description
Features
The AAT3129 is a high efficiency charge pump
DC/DC converter with tri-mode load switch (1X)
fractional (1.5X) and doubling (2X) conversion for
color LED applications. A single current source output provides a regulated current to drive R, G, and
B LEDs via three internal switches. With a simple
single wire serial bus, the RGB module can be easily controlled to display 4096 colors.
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AnalogicTech's Advanced Simple Serial Control™
(AS2Cwire™) serial digital input is used to enable,
disable, and set the duty cycle of each internal
MOSFET switch. Low external parts count (two
1μF flying capacitors and two small bypass capacitors at VIN and OUT) makes the AAT3129 ideally
suited for small battery-powered applications.
ChargePump™
VIN Range: 2.7V to 5.5V
Common Anode RGB LED Control
4096 Color with Single Wire Digital Control
40mA to 180mA Fixed Current Source
AS2Cwire Digital Brightness Control
Low Noise Constant Frequency Operation
Small Application Circuit
Regulated Output Current
No Inductors
1MHz Switching Frequency
IQ <1μA in Shutdown
12-Pin TSOPJW Package
Applications
The AAT3129 has a thermal management system
to protect the device in the event of a short-circuit
condition on any of the output pins. Built-in softstart circuitry prevents excessive inrush current
during start-up. High switching frequency enables
the use of small external capacitors. A low current
shutdown feature disconnects the load from VIN
and reduces quiescent current to less than 1μA.
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The AAT3129 is available in a Pb-free, 12-pin
TSOPJW package.
Fashion RGBs
Mobile Handsets
MP3 Players
PDAs
Portable Devices
RGB Color LEDs
RGB Photo Flash
Smart Phones
Typical Application
VIN
ISRC
C1+
VBAT
CP
CIN
1μF
CCP
1μF
AAT3129
C1
1μF
R
C1C2+
G
B
C2
1μF
C2EN/SET
EN/SET
DR
DG
DB
GND
3129.2007.01.1.4
1
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Pin Descriptions
Pin #
Symbol
Function
1
C2+
Flying capacitor 2 positive terminal. Connect a 1μF capacitor between C2+ and C2-.
2
CP
Charge pump output. Requires 1μF capacitor connected between this pin and
ground.
3
C1-
Flying capacitor 1 negative terminal.
4
C1+
Flying capacitor 1 positive terminal. Connect a 1μF capacitor between C1+ and C1-.
5
ISRC
Current source output.
6
EN/SET
7
DB
Open drain switch blue diode cathode.
8
DG
Open drain switch green diode cathode.
9
DR
Open drain switch red diode cathode.
10
GND
11
IN
12
C2-
AS2Cwire control pin.
Ground.
Input power supply. Requires 1μF capacitor connected between this pin and ground.
Flying capacitor 2 negative terminal.
Pin Configuration
TSOPJW-12
(Top View)
C2+
CP
C1C1+
ISRC
EN/SET
2
1
12
2
11
3
10
4
9
5
8
6
7
C2IN
GND
DR
DG
DB
3129.2007.01.1.4
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Absolute Maximum Ratings1
Symbol
VIN
VCP
VEN/SET
VEN/SET(MAX)
TJ
TLEAD
Description
Input Voltage
Charge Pump Output
EN/SET to GND Voltage
Maximum EN/SET to Input Voltage
Operating Junction Temperature Range
Maximum Soldering Temperature (at leads, 10 sec)
Value
Units
-0.3 to 6
-0.3 to 6
-0.3 to 6
0.3
-40 to 150
300
V
V
V
V
°C
°C
Value
Units
625
160
mW
°C/W
Thermal Information
Symbol
PD
θJA
Description
Maximum Power Dissipation
Thermal Resistance
2, 3
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. Mounted on an FR4 board.
3. Derate 6.25mW/°C above 25°C.
3129.2007.01.1.4
3
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Electrical Characteristics1
VIN = 3.5V, CIN = CCP = C1 = C2 = 1μF; TA = -40°C to +85°C. Unless otherwise noted, typical values are TA = 25°C.
Symbol
Description
Input Power Supply
VIN
Operation Range
ICC
Operating Current
ISHDN
ISRC
Charge Pump
TS
FCLK
η
Switches
RDS(ON)
EN/SET
VEN(L)
VEN(H)
TEN/SET LO
TEN/SET HI MIN
TOFF
TLAT
IEN/SET
Shutdown Current
Output Current Accuracy
Conditions
Min
Typ
Max
Units
1
5.5
3
V
mA
1
5
μA
%
2.7
3.0 ≤ VIN ≤ 5.5, CP = 1.5X,
No Load Current
EN = 0
3.0 ≤ VIN ≤ 5.5
Start-Up Delay Time
Clock Frequency
Efficiency
VIN = 3.5V
Switch On Resistance
VIN = 3.5V, TA = 25°C
Enable Threshold Low
Enable Threshold High
EN/SET Low Time
Minimum EN/SET High Time
EN/SET Off Timeout
EN/SET Latch Timeout
EN/SET Input Leakage
VIN = 2.7V
VIN = 5.5V
-5
200
1
93
1.4
0.3
μs
MHz
%
1.5
Ω
0.4
V
V
μs
ns
μs
μs
μA
75
50
VEN/SET = 5.5V, VIN = 5.5V
-1
500
500
1
1. The AAT3129 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.
4
3129.2007.01.1.4
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Typical Characteristics
Turn-On to 1X Mode
Turn-On to 1.5X Mode
(VIN = 4.2V; ISRC = 60mA)
(VIN = 3.6V; ISRC = 60mA)
EN/SET
(2V/div)
EN/SET
(2V/div)
CP
(2V/div)
CP
(2V/div)
IISRC
(50mA/div)
IISRC
(50mA/div)
μs/div
100μ
μs/div
100μ
Turn-On to 2X Mode
Turn-Off from 1.5X Mode
(VIN = 2.8V; ISRC = 60mA)
(VIN = 3.6V; Addr = 2; Data = 16)
EN/SET
(2V/div)
EN/SET
(2V/div)
VISRC
(2V/div)
CP
(2V/div)
IISRC
(50mA/div)
IISRC
(50mA/div)
μs/div
100μ
3129.2007.01.1.4
μs/div
100μ
5
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Typical Characteristics
Operating Characteristics
Operating Characteristics
(VIN = 4.2V; DR, DB, and DG in 1X Mode)
(VIN = 3.9V; DR and DG in 1X Mode; DB in 1.5X Mode)
4.1V
CP
(1V/div)
CP
(1V/div)
VISRC
(1V/div)
VISRC
(1V/div)
IISRC
(50mA/div)
IISRC
(50mA/div)
μs/div
100μ
5.2V
3.8V
μs/div
100μ
Operating Characteristics
Line Response
(VIN = 3.6V; DR in 1X Mode; DG and DB in 1.5X Mode)
(1X Mode; IISRC = 60mA)
5.3V
CP
(1V/div)
VISRC
(1V/div)
3.5V
VIN
(1V/div)
VCP
(1V/div)
3.7V
4.2V
VISRC
(1V/div)
IISRC
(50mA/div)
IISRC
(50mA/div)
μs/div
100μ
1ms/div
Line Response
(1X, 1.5X Mode; IISRC = 60mA)
VIN
(1V/div)
VCP
(1V/div)
3.5V
3.9V
VISRC
(1V/div)
IISRC
(50mA/div)
1ms/div
6
3129.2007.01.1.4
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Typical Characteristics
Oscillator Frequency vs. Temperature
Shutdown Current vs. Temperature
1
1.5
Shutdown Current (μA)
1.4
FOSC (MHz)
1.3
1.2
1.1
1
0.9
0.8
0.7
0.6
0.5
-40
-20
0
20
40
60
80
0.1
0.01
0.001
-40
100
-20
0
20
Temperature (°°C)
60
80
100
Temperature (°°C)
IISRC vs. VIN
IISRC vs. VF
(VF = 3.5V)
(VIN = 3.5V)
64
64
63
63
+25°C
62
62
61
+25°C
61
IISRC (mA)
IISRC (mA)
40
60
+85°C
59
58
57
60
+85°C
59
58
57
-40°C
56
56
55
55
54
-40°C
54
2.7
3.0
3.3
3.5
3.8
4.1
4.4
4.7
4.9
5.2
1.0
5.5
1.5
2.0
2.5
VIN (V)
3.0
3.5
4.0
VF (V)
TLAT vs. VIN
TOFF vs. VIN
450
350
400
-40°C
300
350
TOFF (μ
μs)
TLAT (μ
μs)
300
250
+85°C
+25°C
200
150
100
-40°C
250
200
+85°C
+25°C
150
100
50
50
0
2.7
3.0
3.3
3.5
3.8
4.1
4.4
Input Voltage (V)
3129.2007.01.1.4
4.7
4.9
5.2
5.5
2.7
3.0
3.3
3.5
3.8
4.1
4.4
4.7
4.9
5.2
5.5
Input Voltage (V)
7
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Typical Characteristics
Switch Resistance vs. Supply Voltage
VIH vs. VIN
1050
1000
1.2
+85°C
950
1.0
VIH (mV)
Switch Resistance (Ω
Ω)
1.4
0.8
0.6
850
800
750
+85°C
+25°C
700
-40°C
+25°C
-40°C
900
650
0.4
600
0.2
550
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
Supply Voltage (V)
2.7
3.0
3.3
3.5
3.8
4.1
4.4
4.7
4.9
5.2
5.5
Input Voltage (V)
VIL vs. VIN
1050
1000
VIL (mV)
950
900
-40°C
850
800
750
700
+25°C
650
+85°C
600
550
2.7
3.0
3.3
3.5
3.8
4.1
4.4
4.7
4.9
5.2
5.5
Input Voltage (V)
8
3129.2007.01.1.4
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Functional Block Diagram
VIN
Soft Start
1MHz
Oscillator
C1+
1X
1.5X
2X
Charge
Pump
Voltage
Reference
C1C2+
C2CP
ISRC
DR
EN/SET
AS2Cwire
Interface
DG
Control
DB
GND
Functional Description
become close to dropout, the charge pump will
automatically transition to 2X mode.
The AAT3129 is a tri-mode load switch (1X) and
high efficiency (1.5X or 2X) charge pump device
intended for fashion color LED lighting applications.
To maximize power conversion efficiency, an internal sensing circuit monitors the voltage required on
the constant current source output and sets the
load switch and charge pump modes based on the
input battery voltage and the current source output
voltage. As the battery discharges over time, the
AAT3129 charge pump is enabled when the current
source output nears dropout. The charge pump initially starts in 1.5X mode. If the charge pump output drops enough for the current source output to
The AAT3129 requires only four external components: two 1μF ceramic capacitors for the charge
pump flying capacitors (C1 and C2), one 1μF
ceramic input capacitor (CIN), and one 0.33μF to
1μF ceramic output capacitor (CP).
3129.2007.01.1.4
The color and brightness of an RGB color LED is
maintained by PWM signals, which are programmed via the AS2Cwire interface. The control
block generates three gate drive PWM signals for
the N-channel MOSFET switches. Please refer to
the interface description and timing in the following
section for details.
9
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Applications Information
pin has been held high for time TLAT. Address or
data is differentiated by the number of EN/SET rising
edges. Since the data registers are 4 bits each, the
differentiating number of pulses is 24 or 16, so that
address 1 is signified by 17 rising edges, address 2
by 18 rising edges, and so forth. Data is set to any
number of rising edges between 1 and including 16.
A typical write protocol is a burst of EN/SET rising
edges, signifying a particular address, followed by a
pause with EN/SET held high for the TLAT timeout
period, a burst of rising edges signifying data, and a
TLAT timeout for the data registers. Once an address
is set, then multiple writes to the corresponding data
register are allowed.
AS2Cwire Serial Interface
The Advanced Simple Serial Control digital interface
is used to set the color, overall intensity, and method
of update for the R, G, and B channels. The intensity for each channel is set by dedicated 4-bit registers
giving each channel 16 levels of brightness and
resulting in 4096 possible color combinations. In
addition to the three color registers, there is an intensity register and a mode register. The intensity register sets the overall intensity and provides 16 global brightness levels. The mode register toggles the
method of update between two possibilities.
Depending on the mode register setting, the
AAT3129 will update the R, G, and B channels
immediately or update them only when the intensity
register is updated.
When EN/SET is held low for an amount of time
greater than TOFF, the AAT3129 enters into shutdown mode and draws less than 1μA from the supply. Address 1 is the default address on the first rising edge after the AAT3129 has been disabled.
When shutdown mode is entered, the Address and
Data registers are reset to 1.
AS2Cwire relies on the number of rising edges of the
EN/SET pin to address and load the registers.
AS2Cwire latches data or address after the EN/SET
AS2Cwire Serial Interface Timing
Address
Data
THI
TLO
T LAT
T LAT
EN/SET
1
2
17
18
1
2...
1
Address
n <= 16
2
G
1
R, B, T, M
1
n
AS2Cwire Serial Interface Addressing
10
Address
EN/SET Rising Edges
Data Register
Description
1
2
3
4
5
17
18
19
20
21
R
G
B
T
M
Red
Green
Blue
Intensity
Mode
3129.2007.01.1.4
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Color Registers R, G, and B
Intensity Register T
The individual color brightness is set using the
three R, G, and B registers. The data register contents determine the on-time for each color channel
during a PWM cycle. The first level is 0, or off, and
is set with a single EN/SET rising edge. This setting
eliminates a given color from the spectrum. The
remaining 15 levels progressively increase the
brightness for a particular color by increasing that
channel’s on-time. Using the red channel as an
example, the resulting on-time is
The overall intensity level is set by the T register.
Once a particular mixing of colors is set to produce
the desired color, the overall intensity can be
adjusted while keeping constant the ratio of colors
to one another. The brightest level is set by programming the T register with 1 edge. Programming
the T register with 16 edges produces the dimmest
setting. The T register adjusts the overall intensity
by controlling the PWM off-time. Under the
dimmest setting, the off-time is the longest. The offtime that results from the data in the T register is
on-time = (R - 1) · 128μs
off-time = (T - 1) · 512μs
where R is the data setting (from 1 to 16). The
same applies to G and B.
Diode Current Timing
(R - 1) · 128μs
Red
ISRC
128μs
(T - 1) · 512μs
ISRC
(G - 1) · 128μs
Green
ISRC
128μs
(B - 1) · 128μs
Blue
Mode Register M
The mode register determines the method of
update for the R, G, and B channels. When the
mode register is set to 1, the addressed color
updates immediately. When the mode register is
set to 2, the colors will update when the T register
is written (synchronized updating).
Under immediate updating, an addressed channel
will update as soon as new data has latched for it.
Under synchronized updating, the channels that
have been assigned new data will not update until
data for the T register latches.
3129.2007.01.1.4
ISRC
128μs
By using synchronized updating, discrete changes
in color can be achieved. Synchronized updating
allows the intensity for all three colors to be updated simultaneously. All three color registers can be
loaded with new data prior to the update. Then,
upon loading the T register, all three colors will
change to their new states together. This allows a
user to transition from one mixed color to another
without having to traverse intermediate colors.
Under immediate updating color changes can only
be achieved serially, or one color at a time.
11
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Mode Register Settings - Address 5
M Setting
1
2
Action
R, G, B, T Registers Latched Independently
R, G, B Registers Synchronized to T Register Latch
LED Current
The resulting DC current for each of the R, G, and B channels depends on the overall system settings. Using the
overall settings, the current for a particular channel is calculated as
R-1
IR = ISRC · 4 · (T - 1) + (R - 1) + (G - 1) + (B - 1) + CHLS_ON
G-1
IG = ISRC · 4 · (T - 1) + (R - 1) + (G - 1) + (B - 1) + CHLS_ON
B-1
IB = ISRC · 4 · (T - 1) + (R - 1) + (G - 1) + (B - 1) + CHLS_ON
where ISRC is the factory programmed current and
CHLS_ON is the number of channels programmed
to operate. Whenever a channel is programmed to
Data = 1, that channel is programmed to off and
must be removed from the CHLS_ON count.
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 100mΩ. For best
overall performance, 1μF capacitors are recommended. Depending on ripple requirements, the
input and output capacitor values can be increased
or decreased accordingly. If lower ripple is desired,
increase the capacitor value. The peak-to-peak ripple seen at the input or output increases or
decreases with capacitor size.
12
Capacitor Characteristics
Ceramic composition capacitors are highly recommended over all other types of capacitors for use
with the AAT3129. 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-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.
3129.2007.01.1.4
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Ceramic Capacitor Materials
Layout Considerations
Ceramic capacitors less than 0.1μF are typically
made from NPO or C0G materials. NPO and C0G
materials typically have tight tolerance and are stable over temperature. Larger capacitor values are
typically composed of X7R, X5R, Z5U, or Y5V
dielectric materials. Large ceramic capacitors, typically greater than 2.2μF, are often available in lowcost Y5V and Z5U dielectrics, but capacitors
greater than 1μF are typically not required for
AAT3129 applications.
The AAT3129 is a high-performance device that
operates with a high switching frequency. To ensure
optimal device performance and accommodate the
fast transients generated by the AAT3129 special
attention should be given to the board layout.
The recommended layout is illustrated in Figure 1.
The traces connecting C1 and C2 experience fast
current transients. As a result, the trace lengths for
C1 and C2 should be minimized by placing the
components as closely as possible to the IC. This
will minimize path resistance and reduce ringing
due to the inductance associated with trace length.
For best IC performance, CIN and COUT are placed
as closely as possible to the IN and CP pins and
are connected to a solid ground.
Capacitor area is another contributor to ESR.
Capacitors that are physically large will have a
lower ESR when compared to a smaller capacitor
made from an equivalent material. These larger
devices can improve circuit transient response
when compared to an equal value capacitor in a
smaller package size.
GND
C2
COUT
CIN
C1
GND
Figure 1: Optimal PCB Layout.
3129.2007.01.1.4
13
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
Ordering Information
Output Current
Package
Marking1
Part Number (Tape and Reel)2
60mA
TSOPJW-12
NNXYY
AAT3129ITP-60-T1
All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means
semiconductor products that are in compliance with current RoHS standards, including
the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more
information, please visit our website at http://www.analogictech.com/pbfree.
Package Information
2.85 ± 0.20
+ 0.10
- 0.05
2.40 ± 0.10
0.20
0.50 BSC 0.50 BSC 0.50 BSC 0.50 BSC 0.50 BSC
7° NOM
0.04 REF
0.055 ± 0.045
0.15 ± 0.05
+ 0.10
1.00 - 0.065
0.9625 ± 0.0375
3.00 ± 0.10
4° ± 4°
0.45 ± 0.15
0.010
2.75 ± 0.25
All dimensions in millimeters.
1. XYY = assembly and date code.
2. Sample stock is held on part numbers listed in BOLD.
14
3129.2007.01.1.4
AAT3129
High Efficiency 1X/1.5X/2X Charge Pump
for RGB Color LED Applications
© Advanced Analogic Technologies, Inc.
AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights,
or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice.
Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. AnalogicTech
warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with AnalogicTech’s standard warranty. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed.
AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders.
Advanced Analogic Technologies, Inc.
830 E. Arques Avenue, Sunnyvale, CA 94085
Phone (408) 737- 4600
Fax (408) 737- 4611
3129.2007.01.1.4
15
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