CS5111

Features:

·Linear Regulator
5V ± 2% @ 100mA
·Switching Regulator
1.4A Peak Internal
Switch
120kHz Maximum
Switching Frequency
5V to 26V Operating
Supply Range
·Smart Functions
Watchdog
RESET
ENABLE
·Protection
Overvoltage
Overtemperature
Current Limit
·54V Peak Transient
Capability


Specifications

Logic Inputs/Outputs (ENABLE , SELECT, WDI,RESET ) ..........................................................-0.3V toVLIN
VLIN .......................................................................................................................................-0.3V to 10V
VIN, VREG: DC Input Voltage .................................................................................................-0.3V to 26V
Peak Transient Voltage (40V Load Dump @ 14V VIN).............................................................-0.3V to 54V
VSW Peak Transient Voltage ...............................................................................................................54V
COSC, CDelay, COMP,VFB1, VFB2 .........................................................................................-0.3V to VLIN
Power Dissipation...........................................................................................................Internally Limited
VLIN Output Current ......................................................................................................Internally Limited
VSW Output Current ......................................................................................................Internally Limited
RESETOutput Sink Current .................................................................................................................5mA
ESD Susceptibility (Human Body Model)...............................................................................................2kV
ESD Susceptibility (Machine Model)....................................................................................................200V
Storage Temperature...........................................................................................................-65 to 150°C
Lead Temperature Soldering: Reflow (SMD styles only) .............60 sec. max above 183°C, 230°C peak


Description

The CS5111 is a dual output power supply integrated circuit. It contains a 5V ±2%, 100mA linear regulator, a watchdog timer, a linear output voltage monitor to provide a Power On Reset (POR) and a 1.4A current mode PWM switching regulator. The 5V linear regulator is comprised of an error amplifier, reference, and supervisory functions. It has low internal supply current consumption and provides 1.2V (typical) dropout voltage at maximum load current.

The watchdog timer circuitry monitors an input signal (WDI) from the microprocessor. CS5111 responds to the falling edge of this watchdog signal. If a correct watchdog signal is not received within the externally programmable time, a reset signal is issued.

CS5111 externally programmable active reset circuit operates correctly for an output voltage (VLIN) as low as 1V. During power up, or if the output voltage shifts below the regulation limit, toggles low and remains low for the duration of the delay after proper output voltage regulation is restored. Additionally a reset pulse is issued if the correct watchdog is not received within the programmed time. Reset pulses continue until the correct watchdog signal is received. The reset pulse width and frequency, as well as the Power On Reset delay, are set by one external RC network.

The current mode PWM switching regulator CS5111 is comprised of an error amplifier with selectable feedback inputs, a current sense amplifier, an adjustable oscillator, and a 1.4A output power switch with anti-saturation control. The switching regulator can be configured in a variety of topologies.

The CS5111 is load dump capable and has protection circuitry which includes overvoltage shutdown, current limit on the linear and switcher outputs, and anovertemperature limiter.