With the accelerated industrialization of Advanced Driver Assistance Systems (ADAS), the number of perception cameras mounted in vehicles is rapidly increasing. For L2+ level assisted driving systems, the number of cameras per vehicle has reached 5-15, including front-view, surround-view, rear-view, and cabin monitoring cameras. These cameras work together to achieve functions such as lane keeping, assisted parking, and 360-degree panoramic imaging. Meanwhile, the camera resolution is gradually evolving from 1 million pixels to 2 million and 8 million pixels.

The increased power consumption of cameras imposes higher requirements on power density, especially for power management chips (PMICs), whose PCB size is usually no larger than 20mm x 20mm. Discrete power supply solutions cannot meet these requirements, and highly integrated PMICs have become the preferred choice for automotive camera power supply solutions.

Automotive Vision System

Due to the wide variety of image sensor models, their power supply architecture and timing requirements are diverse. To shorten design time and accelerate product development, PMICs should reduce peripheral components and simplify designs, while also providing adjustable output voltages and timing settings. Potential voltage drop issues in coaxial cables need to be protected promptly to avoid signal integrity problems. In summary, high integration, flexible control, and reliable protection features are the core capabilities.

he SCT61240Q features a wide input voltage range of 4V-19V and includes one medium-voltage DC/DC Buck, two low-voltage DC/DC Bucks, and one high PSRR low-noise LDO. It can provide a complete power supply rail for automotive cameras. Regardless of the design, a single chip can cover the power requirements, optimizing system flexibility.

Automotive Camera PMIC

Ultra-High Integration and Minimal Solution

The SCT61240Q comes in a compact 2.5mm x 3.5mm QFN-18L package, eliminating the need for output voltage divider resistors and Power Good indicator pull-up resistors. It requires only 13 peripheral components for stable operation, maximizing board area savings. With a fixed switching frequency of 2.2MHz, it supports the use of small inductors.

SCT61240Q典型应用电路

Flexible Timing and Output Configuration

The output voltage of the SCT61240Q can be configured using an external resistor, providing 9 different output voltage combinations. The power-up sequencing can also be configured with an external resistor, offering 6 different combinations, meeting the voltage and timing requirements of most mainstream sensors.

High Efficiency, Low Noise Output

The first-stage medium-voltage Buck has a low on-resistance of only 175/75mΩ. The unique adaptive voltage adjustment design optimizes LDO power consumption while ensuring stable operation. The LDO output has a high PSRR, achieving a 40dB PSRR at 1MHz to mitigate imaging ripple problems.

Figure 1. Buck1 Efficiency vs Load Current, VOUT1=3.2V

Figure 2. Buck2 Efficiency vs. Load Current, VOUT2=1.8V

Figure 3. Buck3 Efficiency vs. Load Current, VOUT3=1.2V

VIN=11V, Vo1=3.6V/0.65A, Vo2=1.8V/0.6A, Vo3=1.1V/0.6A, LDO=3.3V/0.25A温升

Complete Protection Features

The SCT61240Q can tolerate input voltages up to 24V, easily handling Power over Coax (PoC) power supplies. It also integrates input over-voltage protection to prevent damage to the chip from high input voltages. In addition, it offers over-voltage, under-voltage, and over-current protection for each output channel, thermal protection, and ensures safe operation of the power system. The output side is also equipped with active discharge functionality, ensuring that the output discharges during shutdown to avoid potential risks caused by residual voltage.

Excellent EMI Performance

The SCT61240Q integrates a spread-spectrum feature, with the two low-voltage Bucks operating out of phase to disperse switching noise spikes, helping the system pass stringent EMI tests.

Product Details

• AEC-Q100 compliant: Operating temperature range: -40°C to 125°C
• Wide input voltage range: 4V-19V
• Synchronous high-voltage Buck 1: Up to 1.2A continuous output current, with adaptive output voltage based on LDO output
• Synchronous low-voltage Buck 2: Up to 0.6A continuous output current, fixed output voltage of 1.8V
• Synchronous low-voltage Buck 3: Up to 1.2A continuous output current, adjustable output voltages: 1.1V/1.2V/1.3V/1.5V
• Low-voltage LDO: Up to 0.3A continuous output current, adjustable output voltages: 2.7V/2.8V/2.9V/3.3V
• Low noise and high PSRR
• Low shutdown current: 1μA
• Fixed 2.2MHz switching frequency
• Integrated frequency jitter for EMI suppression
• FCCM mode
• Minimum conduction time of 60ns
• 6 adjustable power-up timing configurations via external resistors
• 9 adjustable output voltages via external resistors
• Power Good indicator
• Integrated hiccup mode protection features:
  • Input over-voltage protection
  • Output over-voltage/under-voltage protection
  • Over-current protection
  • Adjustable under-voltage lockout
  • Thermal protection
• QFN-18L (2.5mm x 3.5mm) package

This high-integrated PMIC is a perfect solution for automotive cameras, offering efficiency, flexibility, protection, and meeting the stringent requirements of automotive applications.