Power Management ICs

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.


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
Lead-free product


  • MP3 players, digital audio players
  • Digital cameras, GPS, wireless transceiver
  • Portable devices