SG2525 Enhanced high-voltage resonant controllerr

The SG2525 is a double-ended controller specific to series-resonant half bridge topology. Both LLC and LCC configurations are supported. It provides symmetrical complementary duty cycle: the high-side switch and the low-side switch are driven ON/OFF 180° out-of-phase for exactly the same time. Output voltage regulation is obtained by modulating the operating frequency. The deadtime inserted between the turn-off of one switch and the turn-on of the other one is automatically adjusted to best fit the transition times of the half bridge midpoint. To drive the high-side switch with the bootstrap approach, the IC incorporates a high voltage floating structure able to withstand more than 600 V with a synchronous-driven high voltage DMOS that replaces the external fast-recovery bootstrap diode.

The IC enables the user to set the operating frequency range of the converter by means of a high-accuracy externally programmable oscillator.

At startup, in addition to the traditional frequency-shift soft-start (the switching frequency starts from a preset maximum value and then decays as far as the steady-state value determined by the control loop), a proprietary circuit controls the half bridge to prevent hard-switching from occurring in the initial cycles because of the unbalance in the V·s applied to the transformer.

At light load the IC can be forced to enter a controlled burst-mode operation that keeps the converter input consumption as low as possible.

IC protection functions include a current sense input for OCP with frequency shift and delayed shutdown with automatic restart. Fast shutdown with automatic restart occurs if this first-level protection cannot control the primary current. Additionally, the IC prevents the converter from working in or too close to the capacitive mode, to guarantee soft-switching. A latched disable input (DIS) can be used to implement OTP and/or OVP. The combination of these protection features offers the highest degree of safety.

Other functions include a not-latched active-low disable input with current hysteresis, useful for power sequencing or for brownout protection, and an interface with the PFC controller that enables the switching-off of the pre-regulator during fault conditions or during burst-mode operation

技术特性
  • 8 TO 35 V OPERATION
  • 5.1 V REFERENCE TRIMMED TO ± 1 %
  • 100 Hz TO 500 KHz OSCILLATOR RANGE
  • SEPARATE OSCILLATOR SYNC TERMINAL
  • ADJUSTABLE DEADTIME CONTROL
  • INTERNAL SOFT-START
  • PULSE-BY-PULSE SHUTDOWN
  • INPUT UNDERVOLTAGE LOCKOUT WITH HYSTERESIS
  • LATCHING PWM TO PREVENT MULTIPLE PULSES
  • DUAL SOURCE/SINK OUTPUT DRIVERS
管脚定义图
SG2525 功能框图
SG2525 订购信息
订购型号 产品状态 美金价格 数量 封装 包装形式 温度范围 材料声明
SG2525AN Active   1000 PDIP 16 Tube    
SG2525AP013TR Active   1000 SO-16 Tape And Reel    
SG2525AP Active   1000 SO-16 Tube    
DATASHEET
描述 版本 大小
SG2525 : REGULATING PULSE WIDTH MODULATORS 4 937KB