AAT3351IWP-T1

DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump General Description Features The AAT3351 is a low-noise, constant-frequency charge pump DC/DC converter that uses a dual-mode load switch (1x) and fractional (1.5x) charge pump to maximize efficiency for white LED applications. The AAT3351 is capable of driving 4 white LEDs at a total of 120mA from single 2.7V to 5.5V input. The current sinks may be operated individually or in parallel while driving highercurrent LEDs. A low external parts count (two 1µF flying capacitors and two small 1µF capacitors at VIN and VOUT) makes the AAT3351 ideal for small battery-powered applications. • • • • • • • • • Drives up to 4 LEDs at up to 30mA, each Automatic Switching Between 1x and 1.5x Modes 1MHz Switching Frequency Linear LED Output Current Control ▪ Single-wire, S2Cwire Interface ▪ 32-step ±10% LED Output Current Accuracy 3% LED Output Current Matching Low-Current Shutdown Mode Automatic Soft-Start TSOPJW-14 and TDFN33-12 Packages Skyworks' S2Cwire™ serial digital input is used to enable, disable, and set current to one of 32 levels for the LEDs. Applications The AAT3351 is equipped with built-in short-circuit protection. The soft-start circuitry prevents excessive inrush current at start-up and mode transitions. The AAT3351 family is available in Pb-free, space-saving TSOPJW and TDFN33 packages, and operates over the -40°C to +85°C ambient temperature range. • • • • • • Cellular and Smart Phones Digital Still and Video Cameras PDAs Portable Devices Portable Media Players Other White LED Backlighting Typical Application C1 1µF VBATTERY 3.6V C IN 1µF EN/SET S2Cwire Serial Control C1+ C2+ C1- C2- IN OUT C2 1µF C OUT 1µF AAT3351 D1 D2 D3 D4 D1 EN/SET D2 D3 D4 GND Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 1 DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump Pin Descriptions Pin Number TDFN33-12 TSOPJW-14 Name 1 2 D4 2 3 12 11 EN/SET C2- 4 10 C2+ 5 9 OUT 6 8 C1- 7 7 C1+ 8 6 IN 9 5 GND 10 4 D1 11 3 D2 12 1 D3 N/A EP 13, 14 N/A N/C EP Function Backlight LED 4 current sink. D4 controls the current through backlight LED 4. Connect the cathode of backlight LED 4 to D4. If not used, connect D4 to OUT. S2Cwire serial interface control pin. Negative terminal of charge pump capacitor 2. Positive terminal of charge pump capacitor 2. Connect the 1μF charge pump capacitor 2 from C2+ to C2-. Charge pump output. OUT is the output of the charge pump and supplies current to the backlight LEDs. Connect the backlight LED anodes to OUT. Bypass OUT to PGND with a 1μF or larger ceramic capacitor as close to the AAT3351 as possible. Negative terminal of charge pump capacitor 1. Positive terminal of charge pump capacitor 1. Connect the 1μF charge pump capacitor 1 from C1+ to C1-. Power input. Connect IN to the input source voltage. Bypass IN to GND with a 1μF or larger ceramic capacitor as close to the AAT3351 as possible. Ground pin. Backlight LED 1 current sink. D1 controls the current through backlight LED 1. Connect the cathode of backlight LED 1 to D1. If not used, connect D1 to OUT. Backlight LED 2 current sink. D2 controls the current through backlight LED 2. Connect the cathode of backlight LED 2 to D2. If not used, connect D2 to OUT. Backlight LED 3 current sink. D3 controls the current through backlight LED 3. Connect the cathode of backlight LED 3 to D3. If not used, connect D3 to OUT. Not connected. Exposed paddle (bottom). Connect to GND directly beneath package. Pin Configuration TSOPJW-14 (Top View) 2 D3 D4 D2 D1 GND IN C1+ 1 14 2 13 3 12 4 11 5 10 6 9 7 8 N/C N/C EN/SET C2C2+ OUT C1 TDFN33-12 (Top View) D4 EN/SET C2C2+ OUT C1- 1 12 2 11 3 10 4 9 5 8 6 7 D3 D2 D1 GND IN C1+ Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump Absolute Maximum Ratings TA = 25°C unless otherwise noted. Symbol VIN VOUT VEN/SET VEN/SET(MAX) IOUT TJ Description Input Voltage Charge Pump Output EN/SET to GND Voltage Maximum VEN/SET to VIN Voltage (VEN/SET - VIN) Maximum DC Output Current Operating Junction Temperature Range Value Units -0.3 to 6 -0.3 to 6 -0.3 to 6 +0.3 150 -40 to 150 V V V V mA °C Value Units Thermal Information1 Symbol Description PD Maximum Power Dissipation1 θJA Maximum Thermal Resistance TDFN33-122 TSOPJW-143 TDFN33-12 TSOPJW-14 2000 625 50 160 mW °C/W 1. Mounted on 1.6mm thick FR4 circuit board. 2. Derate 25mW/°C above 25°C ambient temperature. 3. Derate 6.25mW/°C above 25°C ambient temperature. Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 3 DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump Electrical Characteristics VIN = 3.6V; CIN = COUT = 1µF; C1 = C2 = 1µF; TA = -40°C to 85°C unless otherwise noted. Typical values are TA = 25°C. Symbol Description Input Power Supply VIN Input Voltage Range IIN Input Operating Current IIN(SHDN) VIN_(TH) LED Current ID_(MAX) ID_(DATA31) ΔI(D_X)/ID_AVG) VD_(TH) Shutdown Current Charge Pump Mode Hysteresis Sink Outputs D1-D4 Current Accuracy D1-D4 Current Accuracy D1-D4 Current Matching1 Hysteresis for Mode Change IOUT(MAX) Charge Pump Maximum Output Current fOSC Clock Frequency VD_(TH) Charge Pump Mode Transition Threshold tSS Charge Pump Startup Time EN/SET S2Cwire Control VENH EN/SET Input High Threshold Voltage VENL EN/SET Input Low Threshold Voltage IEN(LKG) EN Input Leakage Current tEN/SET(HI_MIN) EN/SET Minimum High Time tEN/SET(HI_MAX) EN/SET Maximum High Time tEN/SET(LOW) EN/SET Input Low Time t EN/SET(OFF) EN/SET Input OFF Timeout tEN/SET(LAT) EN/SET Input Latch Timeout3 Conditions Min -40°C ≤ TA ≤ 85°C 1x Mode, ID1 = ID2 = ID3 = ID4 = OFF EN/SET = IN 1.5x Mode, ID1 = ID2 = ID3 = ID4 = OFF EN/SET = GND 1x to 1.5x Transition at Any IDX 2.7 EN/SET = S2C DATA 1 EN/SET = S2C DATA 31 EN/SET = S2C DATA 1, ID1 = ID2 = ID3 = ID4 = 30mA ID1 = ID2 = ID3 = ID4 = 30mA, 1.5x to 1x Mode VIN = 3.0V, VF = 4.0V 27 Typ Max Units 5.5 V 2 4 6 7.2 µA V 33 mA mA ±3 0.15 % 0.25 150 1 0.15 150 EN/SET = IN; VIN - VF = 1V 1.4 EN/SET = IN = 5V 0.4 1 -1 50 0.3 75 75 500 500 Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 V mA MHz V µs 1. LED current match is defined as 100 (IDX - IAVG)/IAVG. 2. 1x mode output impedance is defined as (VIN - VOUT)/IOUT. 3. If the part has been shut down, the latch time will be 500µs longer for soft start of charge pump. 4 1 0.15 30 0.5 mA V V µA ns µs µs µs µs DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump Typical Characteristics VIN = 3.6V, CIN = COUT = C1 = C2 = 1μF; TA = 25°C, unless otherwise noted. No Load Operating Current vs. Input Voltage (1x Mode) No Load Operating Current vs. Input Voltage (1.5x Mode) 2.5 8 2.45 7 2.4 6 IIN (mA) IIN (mA) 2.35 2.3 2.25 2.2 85°C 25°C 0°C -40°C 2.15 2.1 2.05 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5 4 3 85°C 25°C 0°C -40°C 2 1 0 5.5 2.7 3.1 3.5 Input Voltage (V) 4.7 0.60 100 Efficiency (%) 0.40 0.30 0.20 0.10 VF = 3.3V VF = 3.0V VF = 2.7V -15 10 35 60 85 85 70 55 40 2.7 3.1 Temperature (°C) 3.5 3.9 4.3 4.7 5.1 5.5 Input Voltage (V) 1.5x Output Voltage vs. Load Current 1.5x Mode Operating Characteristics (VIN = 3.3V; 30mA/ch Backlight, 1.5x Mode, COUT = 1µF) 5.5 VOUT (AC coupled) 0 (50mV/div) C1+ (2V/div) 5 4.5 4 VIN = 3.3V VIN = 3.6V VIN = 4.2V 3.5 3 5.5 (DATA = 1, 30mA/ch) 0.50 0.00 -40 5.1 Efficiency vs. Input Voltage (30mA/ch) Current Matching (%) 4.3 Input Voltage (V) Backlight Current Matching vs. Temperature Output Voltage (V) 3.9 0 50 100 Load Current (mA) 150 200 C2+ 0 (2V/div) 0 VIN (AC coupled) 0 (20mV/div) Time (1µs/div) Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 5 DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump Typical Characteristics VIN = 3.6V, CIN = COUT = C1 = C2 = 1μF; TA = 25°C, unless otherwise noted. EN/SET Input Latch Timeout vs. Input Voltage EN/SET Input Off Timeout vs. Input Voltage 490 180 440 390 140 TEN/SET(OFF) (µs) TEN/SET(LAT) (µs) 160 120 100 80 -40°C 25°C 85°C 60 40 2.7 3.1 3.5 3.9 4.3 4.7 5.1 290 240 190 40 2.7 1.10 1.00 1.00 VENL (V) VENH (V) 1.10 0.90 0.80 -40°C 25°C 85°C 0.70 0.60 3.9 4.3 4.7 5.1 Input Voltage(V) 4.7 5.1 5.5 0.80 -40°C 25°C 85°C 0.70 0.60 5.5 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5 Input Voltage (V) Turn-On to 1.5x Mode Backlight (VIN = 3.6V; 30mA/ch) (VIN = 3.3V; 30mA/ch) EN (2V/div) 0 EN (4V/div) VOUT (2V/div) 0 VOUT (4V/div) VBL 0 (2V/div) VBL (4V/div) 0 IIN (200mA/div) 0 IIN (400mA/div) 0 6 4.3 0.90 Turn-On to 1x Mode Backlight Time (100µs/div) 3.9 EN Input Low Threshold Voltage vs. Input Voltage 1.20 3.5 3.5 Input Voltage (V) 1.20 3.1 3.1 EN Input High Threshold Voltage vs. Input Voltage 2.7 -40°C 25°C 85°C 140 90 5.5 Input Voltage (V) 340 0 0 Time (40µs/div) Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump Typical Characteristics VIN = 3.6V, CIN = COUT = C1 = C2 = 1μF; TA = 25°C, unless otherwise noted. Turn-Off from 1.5x Mode Backlight (VIN = 3.3V; 30mA/ch) EN (2V/div) VOUT (4V/div) 0 0 VBL (4V/div) 0 IIN (200mA/div) 0 Time (20ms/div) Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 7 DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump Functional Block Diagram IN C1+ C1C2+ Dual-mode Charge Pump 1x/1.5x OUT C24 EN/SET 32-step S2Cwire Backlight Control D1 D2 Control Logic D3 D4 GND Functional Description Application Information The AAT3351 is a high efficiency charge pump white LEDs driver for portable applications which can drive 4 channels at up to 30mA each. Current Level Settings The current sink magnitude is controlled by the EN/SET serial data S2Cwire interface. The interface records rising edges of the EN/SET pin and decodes them into 32 individual current level settings. LED Drivers The AAT3351 is a fractional charge pump and can multiply the input voltage by 1 or 1.5 times. The charge pump switches at a fixed frequency of 1MHz. The internalmode-selection-circuit automatically switches the mode between 1x and 1.5x mode based on the input voltage, LED forward voltage, and load current. This mode switching maximizes the efficiency throughout the entire load range. When the input voltage is high enough, the AAT3351 operates in 1x mode to provide maximum efficiency. If the input voltage drops too low to supply programmed LED current when the battery discharges and the voltage decays, 1.5x mode is automatically enabled. When the battery is connected to a charger and the input voltage increases sufficiently, the device will switch back to 1x mode. LED current level is set via Skyworks' Simple Serial Control (S2Cwire) interface in a linear scale. The LED current decreases linearly with each increasing code in steps of approximately 1mA as shown in Table 1 and Figure 1. S2Cwire Data LED Current (mA) S2Cwire Data LED Current (mA) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 30 29 28 27.1 26.1 25.2 24.2 23.2 22.3 21.3 20.3 19.4 18.4 17.4 16.5 15.5 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 14.5 13.5 12.6 11.6 10.6 9.7 8.7 7.7 6.8 5.8 4.8 3.9 2.9 1.9 1 0.5 Table 1: S2Cwire Data vs. LED Current. 8 Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com 202166A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 12, 2012 DATA SHEET AAT3351 High Efficiency 1x/1.5x Charge Pump 35 LED Current (mA) 30 25 20 15 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 S2Cwire Data Figure 1: S2Cwire Data vs. LED Current. EN/SET Serial Interface edge of EN/SET enables the charge pump, which reaches full capacity after the soft-start time tSS. and initially sets the output LED current to full scale. Once EN/SET has been held in the logic high state for time tLAT, the programmed current is seen at the current sink outputs. The LED current magnitude is controlled by the EN/SET pin using the S2Cwire interface. The interface records rising edges of the EN/SET pin and decodes them into 32 individual current level settings. Code 1 is full scale, and Code 32 is the lowest setting equal to 500µA. The interface resets back to state 1 after the 32nd clock. The EN/ SET counter can be clocked at speeds up to 1MHz, so intermediate states are not visible, but is designed to accommodate a wide range of data rates. The first rising When EN/SET is held low for an amount of time greater than tOFF, the AAT3351 enters into shutdown mode and draws less than 1µA from IN. The internal data register is reset to 0 during shutdown. The EN/SET timing diagram is shown on Figure 2. THI TLO TOFF TLAT EN/SET 1 Data Reg 2 n-1 n