LT8471 Dual Multitopology DC/DC Converters with 2A Switches and Synchronization FeaTuresDescripTion n Dual 2A and One 500mA, 50V Internal Power The LT®8471 is a dual PWM DC/DC converter containing Switch Channels two internal 2A, 50V switches and an additional 500mA n 2A Primary Channels Can Be Buck, Boost, SEPIC, switch to facilitate step-down and inverting conversion. ZETA, Flyback or Inverting DC/DC Converter Each 2A channel can be independently configured as a n 500mA Skyhook Channel Efficiently Generates buck, boost, SEPIC, flyback or inverting converter. Ca- Boosted Input Voltage pable of generating positive and negative outputs from a n Wide Input Voltage Range of 2.6V to 50V single input rail, the LT8471 is ideal for many local power n UVLO and OVLO Programmable on OV/UV Pin supply designs. n Soft-Start Programmable for Each Channel The LT8471 has an adjustable oscillator, set by a resistor n Fixed Frequency PWM (Set by RT Pin or placed from the RT pin to ground. Additionally, the LT8471 Synchronized to External Clock) can be synchronized to an external clock. The free running n Anti-Phase Switching Reduces Input Ripple or synchronized switching frequency range of the part can n 20-Lead TSSOP and 28-Lead QFN Packages be set between 100kHz and 2MHz. applicaTions Additional features such as frequency foldback, soft-start, and power good are integrated. The LT8471 is available in n Dual Rail Power for Signal Chain. 20-lead TSSOP and 28-Lead (4mm × 5mm) QFN packages. n Buck/Buck, Buck/Boost, Boost/Boost, Boost/Invert, Invert/Invert, Buck/Invert L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical applicaTion6V to 32V to ±5V, Dual DC/DC ConverterEfficiency and Power LossLoad from VOUT1 to VOUT2 VIN1 90 4 1µF V 10µH IN2 VOUT1 1µF SHOUT E1 5V 80 1.5A 316k 70 EFFICIENCY 3 6V TO 32V C1 POWER LOSS ( 47µF 60 2.2µF 2.2µF FB1 ×2 59k 50 POWER LOSS 2 15µH LT8471 GND 40 C3 W 59k EFFICIENCY (%) 475k 30 OV/UV FB2 47µF 1 V ×2 20 CC = 100k 6V 316k PG1 18V V 10 OUT2 E2 32V –5V 100k 0 0 0.65A PG2 0 0.2 0.4 0.6 0.8 1.0 C2 10µH LOAD CURRENT (A) 8471 F10b SS1 SS2 SYNC RT 2.2µF 0.1µF 0.1µF 187k 8471 TA01a 8471fd For more information www.linear.com/8471 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Related Parts