DESCRIPTION The CS5111 is a dual output power integrated circuit. It contains a 5V±2%, 100mA linear regulator, watchdog timer, linear output voltage monitor to provide power-on reset (POR) and a 1.4A current mode PWM switching regulator. The 5V linear regulator is composed of an error amplifier, reference and supervisory functions. It has low internal supply current consumption and provides a maximum dropout voltage load current of 1.2V (typ). A watchdog timer circuit monitors the input signal (WDI) from the microprocessor. It responds to the falling edge of this watchdog signal. If the correct watchdog signal is not received within an externally programmable time, a reset signal is issued. Externally programmable active reset circuit operates with correct output voltage (VLIN) down to 1V. At power-up, or if the output voltage changes below the regulatory limit, switching low and still low for a time after the appropriate output voltage delay regulation is restored. Also the reset pulse is correct, the watchdog will be issued when the programmed time is not received. The reset pulse continues until the correct watchdog is signaled. The reset pulse width and frequency, as well as the power-on-reset delay power, are determined by an external RC network. The current mode PWM switching regulator is controlled by an error amplifier with selectable feedback input, a current sense amplifier, an adjustable oscillator, and a 1.4A output power switch with anti-saturation. The switching regulators can be configured into various topologies. The CS5111 is load dump capable, has protection circuitry including overvoltage shutdown, current limiting linear and switching outputs and an overtemperature limiter.

Features Linear Regulator 5V Halogen @ 100mA 2%
Switching Regulator 1.4A Peak Intra-Switching to 120kHz Maximum Switching Frequency 5V to 26V Operating Supply Range Smart Features Watchdog Protection Over Voltage Thermal Current Limiting
54V transient peak capability