Advanced Analog Technology, Inc. AAT1501/A Details are subject to change without notice REGULATED CHARGE PUMP DC/DC CONVERTERS FEATURES GENERAL DESCRIPTION Monitored Output Voltage The AAT1501/A is a charge pump DC/DC (AAT1501: VO = 5V ± 4% ) converter mainly used for white LED backlighting. It operates with an input voltage ranging from 2.7V (AAT1501A: VO = 4.5V ± 4% ) to 5.0V to generate constant 5.0V (AAT1501) or Output Current: 120mA ( VDD = 3.3V) 4.5V (AAT1501A) output. The regulated output is 150mA ( VDD = 3.6V) produced by using an internal feedback switched capacitor voltage doublers. Input Voltage Range: 2.7V to 5.0V A Power-Saving Shutdown Current of less than 1µA The AAT1501/A requires no external inductor Internal Oscillation Frequency : 750kHz when operating. By using a flying capacitor, the AAT1501/A can deliver up to 120mA ( VDD = 3.3V) Compact SOT-23-6 Package 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, PIN CONFIGURATION portable, battery-powered applications. AAT1501/A comes in a compact 6-pin SOT-23 package to offer users optimal and economical VO C F+ GND VDD SHDN C F− power management solution. – 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 ) Storage Temperature Range Operating Temperature Range SYMBOL VDD VO VALUE 6 UNIT V 6 V VI 6 V Tstorage − 45 to + 125 o TC − 40 to + 85 o 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 SYMBOL TEST CONDITION Supply Voltage VDD Supply Current I DD VDD =2.7V to 5.0V, I O =0 , SHDN = VDD VDD =2.7V to 5.0V, MIN TYP MAX UNIT 2.7 5.0 V - 1.5 2.0 mA - 0.01 1.00 µA kHz Shutdown Current I SHDN Oscillation Frequency f OSC - 750 - Thermal Shutdown TSHDN - 160 - ο C Thermal Shutdown Hysteresis THYS - 20 - ο C OUTPUT PERFORMANCE PARAMETER SYMBOL VOUT Output Voltage Output Current I O =0 , SHDN = 0V IO TEST CONDITION AAT1501 4.8 5.0 5.2 V AAT1501A 4.3 4.5 4.7 V VDD =3V, SHDN = VDD 80 - - - 150 50 - - 18 83 - - 93 - Short Current VOR Output Ripple VDD =3V, I O =50mA VDD =3V, I O =30mA VDD =2.7V, I O =30mA η Efficiency CONTROL INPUT PARAMETER Input Current MIN TYP MAX UNIT VDD =3V, VO =5V / I O =10 mA SYMBOL TEST CONDITION I SHDN SHDN = 0 ~ VDD mA mV % MIN - SHDN High Voltage VIH 1.1 SHDN Low Voltage VIL - TYP MAX UNIT ±0.1 ±1 µA V 0.5 V – 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+ CF− VDD 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− GND C F+ VO C FLY 1µF VO CO 10µF VDD 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− GND C F+ VO C FLY 0.22 µF VO CO 2.2 µF SHDN VDD 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 0.1µF to 1µF, 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 TYP MAX A ------ ------ 1.45 A1 ------ ------ 0.15 A2 0.90 1.15 1.30 b 0.30 ------ 0.50 c 0.08 ------ 0.22 D 2.90 BSC E 2.80 BSC E1 1.60 BSC e 0.95 BSC e1 1.90 BSC L 0.30 0.45 L1 0.60 REF L2 0.25 BSC 0.60 R 0.10 ------ ------ R1 0.10 ------ 0.25 o θ 0 θ1 5o o 4 10o 8o 15 o NOTE: 1 JEDEC OUTLINE: MO-178 AB – 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 ± 0.0025 X.XXX ± 0.006 X.XX ± 0.025 X.X ± 0.10 X ± 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