MAX868EUB+T (MAXIM INTEGRATED PRODUCTS)

The MAX868EUB+T is a regulated, adjustable -2x inverting charge pump in 10 pin µMAX package. This inverting charge pump provides a low cost and compact means of generating a regulated negative voltage up to -2 x VIN from a positive input voltage between 1.8V and 5.5V. It uses a pulse frequency modulation (PFM) control scheme to generate regulated negative output voltage. PFM operation is obtained by gating internal 450KHz oscillator on and off as needed to maintain output voltage regulation. This unique on-demand switching scheme gives the MAX868 excellent light-load efficiency without degrading its full load operation (up to 30mA), permitting smaller capacitors to take advantage of oscillator's high switching frequency. It requires no inductors, only four capacitors to build a complete DC-DC converter. Output voltage regulation is achieved by adding just two resistors. It is used in small LCD panels, cordless phones, camcorders and battery-operated equipment.