The present invention discloses a battery powered apparatus with the circuit of integrated power management and charger unit. It mainly comprises a power management and charger unit, a battery powered device, a battery and an adaptor. By integrating the charger unit, the power switch and the programmable current source to the micro-processor, the micro-processor can properly control the power supplied from the adaptor to the battery under the charging mode operation, which further derives a smoother curve of charging current.