High precision voltage tracker for automotive

Automotive vehicles are equipped with an increasing number of electronic systems for various purposes; all these circuits are powered from a primary supply followed by several secondary power management ICs. In particular, off-board sensors are wired throughout the vehicle and, therefore, require additional safety measures to ensure that a shared power supply of the sensor, ECU, or other essential circuits remains operational in the event of a failure in the sensor devices.

Therefore, it is a popular measure to use so-called Voltage Trackers as a buffer power supply, where a reference supply voltage is replicated with high tracking accuracy and the safety level of the electronic system is generally increased.

The NJW4250 voltage tracker operates up to an absolute maximum voltage of 45V and provides an output current of 50mA. The adjustable input reference voltage ranges from 2.5V to 36V and is replicated to the tracking output voltage with a guaranteed accuracy of ±5mV over the entire operating temperature range. The NJW4250 has protection circuits such as thermal shutdown and over-current protection, which are ideal for off-board sensors in automotive applications and ensures high reliability. The low quiescent current of 40μA and small SOT-23-5 package make the NJW4250 an energy-efficient and space-saving solution.

Specifications NJW4250:

• Operating voltage (Abs. Max.): 4.0V to 40V (45V)
• Adjustable reference input voltage: 2.5V to 36V
• High accuracy tracking output voltage: ±5mV
• Output current: 50mA (Min.)
• Low quiescent current: 40µA (Typ.)
• Ripple rejection: 80dB
• Common pin for reference voltage and ON/OFF control
• Compatible with low ESR ceramic capacitors
• Thermal shutdown
• Overcurrent protection
• AEC-Q100 Grade 1 qualification in progress
• Operating temperature: –40°C to 125°C
• Package NJW4250F: SOT-23-5 (2.9 x 2.8 x 1.1mm)
• Datasheet: NJW4250