Description
The TDA 4862 is excellent convenient for designing a preconverter in ballasts and switched mode power supplies with sinusoidal line current consumption and a power factor approaching unity.
The TDA 4862 controls a boost converter as an active harmonics filter in a discontinuous mode (free oscillating triangular shaped current mode).
The TDA 4862 comprises an internal start-up timer, a high gain voltage amplifier, an one quadrant multiplier for approaching unity power factor, a zero current detector, PWM and logic circuitry, and totem pole MOSFET gate driver.
Protective features are: input undervoltage lockout with hysteresis, VCC zener clamp, cycle-by-cycle current limiting, output voltage limiting for fast and slow load changes up to open circuit, and a sinking gate driver current activated whenever undervoltage mode occurs.
The output voltage of this preconverter is regulated with high accuracy. Therefore the device can be used for world-wide line voltages without switches.
The TDA 4862 is the improved version of the TDA 4817 with a pinout equivalent to world standard.

FEATUREs
• IC for sinusoidal line-current consumption
• Power factor approaching 1
• Controls boost converter as an active harmonics filter
• Internal start-up with low current consumption
• Zero current detector for discontinuous operation mode
• High current totem pole gate driver
• Trimmed ± 1.4% internal reference
• Undervoltage lock-out with hysteresis
• Very low start-up current consumption
• Pin compatible to world standard
• Fast overvoltage regulator
• Current sense input with internal low pass filter