DESCRIPTION

· The S-8340/8341 Series is a CMOS step-up switching regulator controller with high oscillation frequencies of 300 kHz or 600 kHz, designed for efficient step-up switching regulation with high output current.

· It includes a reference voltage source, oscillation circuit, error amplifier, phase compensation circuit, and either a PWM control circuit (S-8340) or a PWM/PFM switching control circuit (S-8341).

· The S-8340 Series offers low ripple, high efficiency, and excellent transient characteristics with a PWM control circuit that adjusts the duty ratio linearly from 0 to 82%.

· The S-8341 Series ensures high efficiency across all load ranges by switching between PWM control (duty ratio ≥27%) and PFM control (duty ratio <27%).

· Ideal for portable devices, it is available in an 8-Pin TSSOP package.

FEATURES

· Oscillation frequency: 600 kHz (A and B types), 300 kHz (C and D types).

· Output voltage: Selectable in 0.1 V steps between 2.5 to 6.0 V (fixed output type) or externally settable via FB terminal (V_FB = 1.0 V).

· Output voltage accuracy: ±2.0%.

· Duty ratio: 0 to 82% (S-8340), 27 to 82% (S-8341 A and B types), 21 to 82% (S-8341 C and D types).

· Low-voltage operation: Starts oscillation at V_DD = 0.9 V.

· Built-in current limit circuit, soft-start function, and shutdown function.

· External components required: Coil, diode, capacitors (3), transistor, and resistor.

· Lead-free, Sn 100%, halogen-free.

APPLICATIONS

· Power supplies for portable devices such as PDAs, electronic notebooks, and cellular phones.

· Power supplies for audio equipment like portable CD players, MD players, and headphone stereos.

· Main or local power supplies for notebook PCs and peripherals.

· Constant voltage power supplies for cameras, VCRs, and communication devices.