DESCRIPTION

· The S-8340/8341 Series is a CMOS step-up switching regulator controller designed for high efficiency and high output current.

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

· The series operates at high oscillation frequencies of 300 kHz or 600 kHz, enabling efficient step-up regulation with minimal external components.

· The S-8340 offers low ripple and excellent transient characteristics with a duty ratio of 0 to 82%.

· The S-8341 switches between PWM (27% to 82% duty ratio) and PFM control for high efficiency across all load ranges.

· Suitable for portable devices with its 8-Pin TSSOP package and high oscillation frequency.

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).

· Output voltage accuracy: ±2.0%.

· External setting of output voltage via FB terminal (VFB = 1.0 V).

· Requires minimal external components: coil, diode, capacitors, transistor, and resistor.

· 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 VDD = 0.9 V.

· Built-in current limit circuit with external resistor (RSENSE).

· Soft-start function via external capacitor (CSS).

· Shutdown function included.

· Lead-free and halogen-free design.

APPLICATIONS

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

· Power supplies for audio equipment such as 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.