Four Output Mini PMIC for Camera Applications

The MAX25250 is a high-efficiency, four-output PMIC that integrates three DC-DC converters and a high-PSRR LDO, with OV/UV monitoring on all outputs. OUT1 is a1A high-voltage synchronous step-down converter operating from power over coax or car battery. OUT2 and OUT3 low-voltage synchronous step-down converters operate from OUT1 and provide a 0.8V to 3.9875V output voltage range. OUT2 can deliver 1.2A for high megapixel cameras and high-speed serializers. OUT3 can deliver 1.2A to power the secondary rails of the imager, serializer,and MCU. OUT4 is a low-voltage, low-noise, high-PSRR LDO for imager power. All buck converters achieve ±1.5% output voltage accuracy over load, line, and temperature range. Overvoltage and undervoltage faults are monitored and errors are communicated through active-low RESET.

This device features a 2.2MHz fixed-frequency PWM mode for better noise immunity and load-transient response. The high-frequency operation allows for the use of all ceramic capacitors and minimizes external components. The programmable spread-spectrum frequency modulation minimizes radiated electromagnetic emissions. Integrated low-RDS(ON) switches improve efficiency at heavy loads and make layout simpler than discrete solutions.

Sequencing through the use of EN23 and EN4 pins and factory-settable output voltages increases flexibility for different image sensors and configurations. Other features include soft-start, overcurrent, and overtemperature protection. The MAX25250 is specified for operation over the -40°C to +125°C automotive temperature range.

Applications

* Rear-View Cameras * Surround-View Cameras

* Multiple Functions for Small Size

* 1A Synchronous High-Voltage Buck Converter

* Input Voltage Range 5V to 22V

* 3V to 4V, and 5V Output Voltage in 50mV Steps

* Two Synchronous Low-Voltage Buck Converters

* OUT2 and OUT3 Provide up to 1.2A

* 0.8V to 3.9875V in 12.5mV Steps

* LDO for Camera Sensor; 50dB at 1kHz

* 2.2MHz Operation

* Active-Low RESET Output–Open-Drain

* High-Precision

* ±1.5% Output Voltage Accuracy

* OV/UV Monitoring

* Robust for the Automotive Environment

* Current-Mode, Forced-PWM Operation

* Overtemperature and Short-Circuit Protection

* 3.5mm x 3.5mm 20-Pin TQFN

* -40°C to +125°C Grade 1 Automotive Temperature Range

* AEC-Q100 Qualified