STEP-UP, PWM CONTROL or PWM / PFM SWITCHABLE BUILT-IN TRANSISTOR SWITCHING REGULATOR

The S-8353/8354 Series is a CMOS step-up switching regulator which mainly consists of a reference voltage source, an oscillation circuit, a power MOS FET, an error amplifier, a phase compensation circuit, a PWM control circuit (S-8353 Series) and a PWM / PFM switching control circuit (S-8354 Series).
The S-8353/8354 Series can configure the step-up switching regulator with an external coil, capacitor, and diode. In addition to the above features, the small package and low current consumption make the S-8353/8354 Series ideal for portable equipment applications requiring high efficiency.
The S-8353 Series realizes low ripple, high efficiency, and excellent transient characteristics due to its PWM control circuit whose duty ratio can be varied linearly from 0% to 83% (from 0% to 78% for 250 kHz models), an excellently designed error amplifier, and phase compensation circuits.
The S-8354 Series features a PWM / PFM switching controller that can switch the operation to a PFM controller with a duty ratio is 15% under a light load to prevent a decline in the efficiency due to the IC operating current.

FEATUREs
• Low voltage operation: Startup at 0.9 V min. (IOUT = 1 mA) guaranteed
• Low current consumption : During operation 18.7 μA (3.3 V, 50 kHz, typ.)
                                             During shutdown: 0.5 μA (max.)
• Duty ratio : Built-in PWM / PFM switching control circuit (S-8354 Series)
                     15 % to 83 % (30 kHz and 50 kHz models)
                     15 % to 78 % (250 kHz models)
• External parts : Coil, capacitor, and diode
• Output voltage : Selectable in 0.1 V steps between 1.5 V and 6.5 V (for VDD / VOUT separate types)
                             Selectable in 0.1 V steps between 2.0 V and 6.5 V (for other than VDD / VOUT separate types)
• Output voltage accuracy : ±2.4%
• Oscillation frequency : 30 kHz, 50 kHz, and 250 kHz selectable
• Soft start function : 6 ms (50 kHz, typ.)
• Lead-free, Sn 100%, halogen-free*1
*1. Refer to “ Product Name Structure” for details.

APPLICATIONs
• Power supplies for portable equipment such as digital cameras, electronic notebooks, and PDAs
• Power supplies for audio equipment such as portable CD / MD players
• Constant voltage power supplies for cameras, VCRs, and communication devices
• Power supplies for microcomputers