Texas Instruments TPS7B4260-Q1 Low-Dropout (LDO) Voltage Tracker
Texas Instruments TPS7B4260-Q1 Low-Dropout (LDO) Voltage Tracker is designed to reliably provide power to off-board sensors with a wire harness, even in harsh automotive environments. In such severe operating conditions, the cables in the harness are potentially exposed to various fault conditions, increasing the risk of failure. Such conditions include short-to-ground, short-to-battery, and over-temperature. The TPS7B4260-Q1 comes with integrated protection features against each of these fault conditions, as well as protection against reverse polarity. The device incorporates a topology containing two back-to-back P-channel metal-oxide semiconductor field-effect transistors (MOSFETs). This PMOS topology eliminates the need for an external diode that is otherwise required to prevent reverse current flow. The high 300mA current rating of the device potentially allows a single tracker to power multiple off-board sensors simultaneously. The device is designed to handle a 45V (absolute maximum) input voltage and survive the automotive load dump transient conditions.
The Texas Instruments TPS7B4260-Q1 provides a protective buffer for the ADC and MCU against fault conditions, while securely transferring power to the off-board sensors. A reference voltage applied at the adjustable input pin (ADJ/EN) is tracked with a very tight 6mV (max) tolerance at the FB pin. This tolerance holds true for all variations across the specified line, load, and temperature values. This tight tracking tolerance is particularly beneficial for ratiometric sensors whose output is sampled by the ADC. This tolerance ensures minimal errors between the ADC full-scale reference and the sensor power-supply voltage. The ratiometricity of the sensor measurement is thereby maintained.
The output voltage becomes equal to the voltage at the ADJ/EN pin (± the tracking tolerance) by tying the FB pin directly to the OUT pin. If the ADC full-scale reference voltage equals the sensor supply voltage, connect the reference voltage directly to the ADJ/EN pin. Use a resistive divider at the ADJ/EN pin if the sensor supply is lower than the reference. This divider helps scale down the reference voltage to match the sensor supply voltage. Use a resistive divider between the FB and OUT pins if the sensor exceeds the reference. This divider helps scale up the ADC full-scale reference voltage and match the sensor supply voltage.
By setting the ADJ/EN input pin low, the TPS7B4260-Q1 switches to standby mode. In this mode, the LDO's quiescent current consumption is less than 3.8µA. The device is available in an 8-pin HSOIC package.
Features
- AEC-Q100 qualified for automotive applications
- Temperature grade 1 of –40°C to +125°C, TA
- Junction temperature of –40°C to +150°C, TJ
- Wide input voltage range
- Absolute maximum range of –40V to +45V
- Operating range of 3.3V to 40V
- Output voltage
- Wide operating range of 2V to 40V
- Output voltage flexibility: Scale VOUT to values higher or lower than the reference using external resistors in a voltage divider configuration
- Maximum output current of 300mA
- Very tight output-tracking tolerance of 6mV (max)
- 330mV at 200mA low dropout voltage
- Combined enable and reference functionalities
- Low quiescent current at a light load of 60µA
- Stable over a wide range of ceramic output capacitor values
- COUT range of 1µF to 100µF
- ESR range of 1mΩ to 2Ω
- Integrated protection features
- Reverse current protection
- Reverse polarity protection
- Overtemperature protection
- Protection against output short-circuit to ground and supply
- Available in the HSOIC (DDA) low thermal resistance (RθJA = 48°C/W) 8-pin package
Applications
- Powertrain pressure sensors
- Powertrain temperature sensors
- Powertrain exhaust sensors
- Powertrain fluid concentration sensors
- Body control modules (BCM)
- Zone control modules
- HVAC control modules
Additional Resources
Functional Block Diagram
Development Tool
Texas Instruments TRKRLDOEVM-119 Evaluation Module
Evaluates the performance and operation of tracker Low-Dropout (LDO) linear regulators.