POWER LOSS (W) LT8471 Dual Multitopology DC/DC Converters with 2A Switches and Synchronization Fea T Descrip T 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. a T 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, L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Invert/Invert, Buck/Invert Technology Corporation. All other trademarks are the property of their respective owners. Typical a T 6V to 32V to 5V, Dual DC/DC Converter Efficiency and Power Loss Load from V to V OUT1 OUT2 V IN1 90 4 1F 10H V V OUT1 IN2 E1 5V 80 1F SHOUT 1.5A 70 EFFICIENCY 316k 3 6V TO 32V C1 60 47F FB1 2.2F 2.2F 2 50 POWER LOSS 59k 2 15H 40 GND LT8471 C3 30 59k 475k 47F 1 OV/UV V = FB2 20 CC 2 6V 100k 316k 18V 10 PG1 V OUT2 32V E2 5V 0 0 100k 0.65A 0 0.2 0.4 0.6 0.8 1.0 PG2 LOAD CURRENT (A) 10H 8471 F10b C2 SS1 SS2 SYNC RT 2.2F 0.1F 0.1F 187k 8471 TA01a 8471fd 1 For more information www.linear.com/8471 EFFICIENCY (%) ion pplica ions pplica ion uresLT8471 a T e Maxi Mu M r a T (Note 1) V , V Voltages ..................................... 0.3V to 50V SS1, SS2 ................................................... 0.3V to 2.5V IN1 IN2 C1, C2 Voltages .......................................... 0.4V to 50V FB1, FB2 Voltages ..................................... 2.5V to 2.5V E1, E2 Voltages ........................................... 60V to 50V PG1, PG2 Voltages ..................................... 0.3V to 50V V to V and V to V Voltages ............ 0.4V to 60V OV/UV Voltage ............................................. 0.3V to 5V C1 E1 C2 E2 V to V and V to V Voltages SHOUT Voltage ......................................... 0.3V to 50V IN1 E1 IN2 E2 Low Side Configurations (Note 6) .......... 0.4V to 40V Operating Junction Temperature Range High Side Configurations (Note 6) ......... 0.4V to 60V LT8471E (Notes 2, 5) ......................... 40C to 125C V to V and V to V Voltages LT8471I (Notes 2, 5) .......................... 40C to 125C IN1 C1 IN2 C2 High Side Configurations (Note 6) ......... 0.4V to 40V LT8471H (Notes 2, 5) ......................... 40C to 150C C3 Voltage ................................................. 0.4V to 50V Storage Temperature Range .................. 65C to 150C RT Voltage ................................................... 0.3V to 5V Lead Temperature (Soldering, 10 sec) SYNC Voltage ............................................ 0.3V to 5.5V FE Package .......................................................300C p c F T TOP VIEW TOP VIEW C1 1 20 C2 28 27 26 25 24 23 E1 2 19 E2 E1 1 22 E2 V IN1 3 18 V V 2 21 V IN2 IN1 IN2 PG1 PG1 3 20 PG2 4 17 PG2 21 FB1 4 29 19 FB1 FB2 5 16 FB2 GND GND OV/UV 5 18 SS2 OV/UV 6 15 SS2 RT 6 17 SHOUT RT SHOUT 7 14 SS1 7 16 C3 SS1 C3 8 13 SYNC 8 15 NC SYNC GND 9 12 9 10 11 12 13 14 GND GND 10 11 FE PACKAGE 20-LEAD PLASTIC TSSOP UFD PACKAGE 28-LEAD (4mm 5mm) PLASTIC QFN = 38C/W JA EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB = 44C/W, = 8C/W JA JC EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB 8471fd 2 For more information www.linear.com/8471 GND NC GND NC GND C1 GND C2 GND NC GND NC ion igura on in ings bsolu