S-8353/8354 Series STEP-UP, PWM CONTROL or PWM / PFM SWITCHABLE www.ablic.com BUILT-IN TRANSISTOR SWITCHING REGULATOR ABLIC Inc., 2002-2020 Rev.3.1 00 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 A (3.3 V, 50 kHz, typ.) During shutdown: 0.5 A (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 V / V separate types) DD OUT Selectable in 0.1 V steps between 2.0 V and 6.5 V (for other than V / V separate types) DD OUT Output voltage accuracy : 2.4% Oscillation frequency : 30 kHz, 50 kHz, and 250 kHz selectable Soft start function : 6 ms (50 kHz, typ.) *1 Lead-free, Sn 100%, halogen-free *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 Packages SOT-23-3 SOT-23-5 SOT-89-3 1 STEP-UP, PWM CONTROL or PWM / PFM SWITCHABLE BUILT-IN TRANSISTOR SWITCHING REGULATOR S-8353/8354 Series Rev.3.1 00 Block Diagrams (1) A, C and H Types (Without Shutdown Function) CONT VOUT Oscillation circuit IC internal power supply PWMcontrol circuit + or PWM / PFM swiching control circuit Soft start built-in Phase reference power compensation VSS supply circuit Figure 1 (2) A and H Types (With Shutdown Function) CONT VOUT Oscillation circuit IC internal power supply PWMcontrol circuit + or PWM / PFM swiching control circuit Soft start built-in Phase reference power compensation VSS supply circuit ON/ OFF Figure 2 (3) D and J Types (VDD / VOUT Separate Type) CONT VOUTVDD Oscillation circuit IC internal power supply + PWMcontrol circuit or PWM / PFM swiching control circuit Soft start built-in Phase VSS reference power compensation supply circuit Figure 3 2