New PMIC from Renesas Built to Simplify Automotive Cameras
The new power management IC is said to help designers build smaller, less intrusive automotive camera systems.
Renesas’s new power management IC (PMIC), ISL78083, operates from an input voltage range of 4.0V to 42V. It features three buck converters, an LDO regulator, overvoltage/undervoltage monitors, and "power-good" indicators.
Renesas SL78083. Image used courtesy of Renesas
The device includes three separate “power-good” output pins: one for the primary buck regulator, one for the secondary bucks, and one for the LDO.
It also includes a reset output/fault indicator.
For Automotive Cameras
A few applications for the new (PDF) PMIC include rearview HD automotive cameras, surround-view HD automotive cameras, HD dashcams, and driver monitoring cameras.
“The innovative ISL78083 PMIC expands Renesas’ support for automotive surround-view camera systems beyond the image processing capabilities of the R-Car SoC and into the design of the HD satellite cameras,” said Niall Lyne, senior director of the automotive business unit at Renesas.
“Cameras designed with the ISL78083 are smaller and can be conveniently mounted in vehicle locations that provide the desired surround-view camera angles without negatively impacting style or aerodynamics.”
Three Synchronous Buck Regulators, One LDO Regulator
The switching frequency for the buck regulators is 2.2MHz with an available pseudo-random spread spectrum. The four-rail ISL78083’s outputs are factory programmed in order to save board space and external component count.
Block diagram of the ISL78083. Image used courtesy of (PDF) Renesas
There are three synchronous buck regulators. The primary buck regulator’s output can be programmed from 3.3V to 5.05V, while the secondary buck regulators can be set for outputs ranging from 1.0 to 3.3 volts.
The LDO’s range can be set from 2.8V to 3.4V.
Default outputs for the primary buck regulator, the two secondary buck regulators, and the LDO are 3.8V, 1.8V, 1.2V, and 3.3V, respectively.
When the unit is in a shutdown state, the typical input current is less than 1µA. A system reset output pin is available to signal the occurrence of an output fault to the controlling MCU.
Undervoltage and Overvoltage Protection
By default, the under-voltage threshold for the four outputs are set at 92%. The overvoltage thresholds are set at 108%. Other values can be specified for each of the outputs separately.
A typical application for Renesas’s ISL78083 PMIC. Image used courtesy of (PDF) Renesas
When an overvoltage fault is reported, the output voltage remains above the threshold for 10μs (typical). For undervoltages, the figure is 2µs (typical) with factory programming for an additional 10μs.
Physical Considerations
The ISL78083 is available in a 4mm x4mm 24 Lead Step Cut QFN package with an exposed pad for improved thermal performance. It is AEC-Q100 Grade-1 qualified and operates across a temperature range of -40°C to +125°C.
Around the Industry
Dialog Semiconductor's DA9061-A is a PMIC that works with an input range of 2.8V to 5.5V. There are three buck converters with available outputs ranging from 0.3V to 3.34V at up to 2.5A. There are also four LDOs that each provide up to 300mA. The unit includes a rating of AEC-Q100 Grade 2.
Texas Instruments’ TPS650330-Q1 automotive camera PMIC contains three buck converters and one LDO. One of the bucks has an input range of 4V to 18.3V with output up to 1.5A. The other two bucks work with inputs ranging from 3.0V to 5.5V and provide up to 1.2A output. The LDO accepts 3.0V to 5.5V input with up to 300mA output. The unit is AEC-Q100 Grade 1 qualified.
