AAT1501_3

Advanced Analog Technology, Inc. AAT1501/A Details are subject to change without notice REGULATED CHARGE PUMP DC/DC CONVERTERS FEATURES Monitored Output Voltage (AAT1501: VO = 5V ± 4% ) (AAT1501A: VO = 4.5V ± 4% ) Output Current: 120mA ( VDD = 3.3V) 150mA ( VDD = 3.6V) Input Voltage Range: 2.7V to 5.0V A Power-Saving Shutdown Current of less than 1µA Internal Oscillation Frequency : 750kHz Compact SOT-23-6 Package GENERAL DESCRIPTION The AAT1501/A is a charge pump DC/DC converter mainly used for white LED backlighting. It operates with an input voltage ranging from 2.7V to 5.0V to generate constant 5.0V (AAT1501) or 4.5V (AAT1501A) output. The regulated output is produced by using an internal feedback switched capacitor voltage doublers. The AAT1501/A requires no external inductor when operating. By using a flying capacitor, the AAT1501/A can deliver up to 120mA ( VDD = 3.3V) output current for the system. The AAT1501/A’s typical ultra low operating current, and compact external parts make it an ideal component for small, portable, battery-powered applications. AAT1501/A comes in a compact 6-pin SOT-23 package to offer users optimal and economical PIN CONFIGURATION VO C F+ power management solution. GND VDD SHDN C F− – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 1 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A PIN DESCRIPTION PIN NAME I/O DESCRIPTION NO. 1 VO O Output Voltage 2 GND - Ground 3 SHDN I Shutdown Input Pin 4 C F− O Flying Capacitor Negative Terminal 5 VDD - Supply Voltage 6 C F+ I Flying Capacitor Positive Terminal ABSOLUTE MAXIMUM RATINGS CHARACTERISTICS Supply Voltage Output Voltage ( VO , VCF+ , VCF− ) Input Voltage ( VSHDN ) SYMBOL VDD VO VALUE 6 6 UNIT V V VI Tstorage TC 6 − 45 to + 125 − 40 to + 85 V o o Storage Temperature Range Operating Temperature Range C C – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 2 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A ELECTRICAL CHARACTERISTICS, TC = −40° C to + 85° C , VDD =3.3V (Unless Otherwise Specified) OPERATING CONDITION PARAMETER Supply Voltage Supply Current Shutdown Current Oscillation Frequency Thermal Shutdown Thermal Shutdown Hysteresis SYMBOL TEST CONDITION MIN 2.7 TYP MAX UNIT 5.0 1.5 0.01 750 160 20 2.0 1.00 V mA VDD I DD I SHDN f OSC TSHDN THYS VDD =2.7V to 5.0V, I O =0 , SHDN = VDD - VDD =2.7V to 5.0V, I O =0 , SHDN = 0V µA kHz ο C C ο OUTPUT PERFORMANCE PARAMETER Output Voltage Output Current Short Current Output Ripple SYMBOL VOUT TEST CONDITION AAT1501 AAT1501A MIN TYP MAX UNIT 4.8 4.3 80 5.0 4.5 150 50 18 83 93 5.2 4.7 % V V mA IO VOR VDD =3V, SHDN = VDD VDD =3V, I O =50mA VDD =3V, I O =30mA VDD =2.7V, I O =30mA VDD =3V, VO =5V / I O =10 mA mV Efficiency η CONTROL INPUT PARAMETER Input Current SYMBOL TEST CONDITION I SHDN SHDN = 0 ~ VDD MIN 1.1 - TYP MAX UNIT ±0.1 ±1 A V 0.5 V SHDN High Voltage SHDN Low Voltage VIH VIL – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 3 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A BLOCK DIAGRAM CF+ VDD CF− VO SHDN VREF – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 4 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A TYPICAL OPERATING CHARACTERISTICS – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 5 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A TYPICAL OPERATING CHARACTERISTICS – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 6 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A TYPICAL OPERATING CHARACTERISTICS APPLICATION CIRCUIT 1. Heavy Load Circuit VDD CIN 10µF C F− C FLY GND 1µF C F+ VDD VO CO 10µF VO SHDN – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 7 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A APPLICATION CIRCUIT 2. Light Load Circuit VDD CIN 2.2µF C F− C FLY GND 0.22 µF C F+ VO CO 2.2 µF VO V DD DD SHDN APPLICATION CIRCUIT FOR LEDS – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 8 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A APPLICATION CIRCUIT FOR BACKLIGHT DIMMING APPLICATION INFORMATION Operation AAT1501 is a simple white LED driver. It uses charge pump to generate output voltage 2 times larger than input voltage and keeps the output voltage stable by using the comparator of the device. The current of the white LED could be set by an external resistor. Short Circuit Protection AAT1501/A includes a current-limit circuit. Whenever excessive current is generated, the mechanism takes over the output regulation circuit and reduces output current to a typical level of 150mA. LED Current Setting A LED current ( I LED _ ) is set by a resistor, as follows: R_ = VO − VF I LED _ – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 9 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A where: VO is the Monitored Output Voltage (AAT1501:5V, AAT1501A:4.5V). VF is the LED Forward Voltage. Dimming Control 1. Dimming Using PWM at SHDN Pin A PWM signal applied to SHDN can control the LED brightness in direct dependence on the duty cycle. The recommended PWM signal frequency is about 100Hz to ensure a good match between the input signal duty cycle and the LED average current. 2. Dimming Using PWM by a NMOS The additional NMOS can control the LED brightness in direct dependence on the duty cycle as shown in application circuit for backlight dimming, The PWM signal frequency can be up to kHz level. Thermal Shutdown The AAT1501/A includes a thermal-limit circuit that shuts down the IC at approximately +160°C. The device turns on after the IC cools by approximately 20°C. Capacitor Selection For LED applications, input ripple is more important than output ripple. Input ripple depends on the source supply’s impedance. Adding a lowpass filter to the input further reduces input ripple. A charge pump flying capacitor of value between 0.1 F to 1 F, should be connected from C+ to C–. The recommended capacitor’s type is X5R or X7R ceramic capacitor. – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 10 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A PACKAGE DIMENSIONS – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 11 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A PACKAGE DIMENSIONS (Cont.) VARIATION (ALL DIMENSIONS SHOWN IN MILLIMETERS) SYMBOL MIN A A1 A2 b c D E E1 e e1 L L1 L2 R R1 θ θ1 NOTE: 1 JEDEC OUTLINE: MO-178 AB TYP ----------1.15 MAX 1.45 0.15 1.30 0.50 0.22 ----------0.90 0.30 0.08 ----------2.90 BSC 2.80 BSC 1.60 BSC 0.95 BSC 1.90 BSC 0.30 0.45 0.60 REF 0.25 BSC 0.60 0.10 0.10 ----------4 10o o -----0.25 0 o 8o 15 o 5o – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 12 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A Tape and Reel Packing Method: 3,000pcs/reel, 5 reels/box – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 13 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A Tape and Reel (Cont.) X.XXX X X.XXX X.XX X.X X ± 0.0025 ± 0.006 ± 0.025 ± 0.10 ± 0.25 UNIT: MILLIMETERS – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 14 of 15 3.0 Advanced Analog Technology, Inc. AAT1501/A PART MARKING SOT23-6 TOP MARKING AXX NOTE: SOT23-6 HAS NO BACK MARKING. – 台灣類比科技股份有限公司 – – Advanced Analog Technology, Inc. – Page 15 of 15 3.0