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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • 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 • [email protected] • www.skyworksinc.com 202155A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012 13