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New Products / Topics

Step-Up, Super-Small Package, 1.2 MHz PWM Control or PWM/PFM Switchable Switching Regulator Controller S-8365/8366 Series

The S-8365/8366 Series is a CMOS step-up switching regulator controller which mainly consists of a reference voltage source, an oscillation circuit, an error amplifier, a phase compensation circuit, a timer latch short-circuit protection circuit, a PWM control circuit (S-8365 Series) and a PWM / PFM switching control circuit (S-8366 Series).
With an external low-ON-resistance Nch Power MOS, this product is ideal for applications requiring high efficiency and a high output current.
The S-8365 Series efficiently works on voltage's condition of large I/O difference due to the PWM control circuit linearly varies the duty ratio to 90%.
During light-load, the S-8366 Series switches its operation to the PFM control by the PWM / PFM switching control circuit in order to prevent efficiency decline due to the IC operating current.
Ceramic capacitors can be used for output capacitor. Small packages SNT-6A, SOT-23-5 and SOT-23-6 enable high-density mounting.

Features


  • Low operation voltage: Start at 1.1 V (1 mA) guaranteed (in the product without UVLO function)

  • Input voltage range: 1.8 V to 5.5 V

  • Oscillation frequency: 1.2 MHz, 600 kHz

  • Reference voltage: 0.6 V±2.0%

  • Soft start function: 7 ms typ.

  • Low current consumption: 70 µA typ. at switching off

  • Duty ratio: Built-in PWM / PFM switching control circuit (S-8366 Series)
    28% to 85% (1.2 MHz product)
    28% to 90% (600 kHz product)

  • Shutdown function: Current consumption 1.0 µA max. at shutdown

  • External parts: Inductor, diode, capacitor, transistor

  • Timer latch short-circuit protection circuit: Selectable with / without short-circuit protection circuit for each product
    Settable delay time by external capacitor (in the product with short-circuit protection)

  • UVLO (under-voltage lockout) function: Selectable with / without UVLO for each product

  • Small packages: SNT-6A, SOT-23-5, SOT-23-6

  • Lead-free product


Applications

  • MP3 players, digital audio players

  • Digital cameras, GPS, wireless transceiver

  • Portable devices