TPS7A1650QDGNRQ1

The TPS7A1650QDGNRQ1 from Texas Instruments is an AEC-Q100 Grade 1 qualified ultra-low quiescent current low-dropout (LDO) voltage regulator designed for automotive and industrial battery-powered applications. The device accepts input voltages from 3V to 60V and provides a fixed 5.0V output at up to 100mA, making it ideal for generating a 5V logic supply directly from 12V or 24V automotive battery systems without a pre-regulator. The ultra-low 5uA quiescent current (typical) is critical for always-on battery-powered systems where the regulator must remain active while the vehicle is parked, minimizing battery drain over weeks or months. The 60V maximum input voltage provides ample margin for automotive load dump transients (up to 40V) and double-battery jump-start conditions (24V nominal). The 60mV dropout voltage at 20mA load ensures the output remains regulated even when the battery voltage drops during cranking. The power-good (PG) output with programmable delay using an external capacitor allows system power-rail sequencing, informing the microcontroller when the 5V rail is within regulation before enabling other system functions. The enable (EN) pin is compatible with standard CMOS logic, allowing direct control from a microcontroller GPIO. Internal current limiting and thermal shutdown protect the device from fault conditions. The output is stable with ceramic capacitors as small as 2.2uF, enabling compact solution size. Functional safety documentation is available to support ISO 26262 system design.

The TPS7A1650QDGNRQ1 operates as a low-dropout linear voltage regulator with ultra-low quiescent current. Key subsystems include: (1) Pass Transistor – a P-channel MOSFET pass element connects VIN to VOUT; the error amplifier drives the pass transistor gate to regulate VOUT at 5.0V; the PMOS architecture allows low dropout (VIN can be close to VOUT) and eliminates the need for a charge pump; (2) Ultra-Low IQ Design – the internal bias circuitry and error amplifier are designed to consume only 5uA total quiescent current at no load; this is achieved through sub-threshold biasing techniques and minimal internal loading; the 1uA shutdown current further reduces battery drain when the device is disabled via the EN pin; (3) Error Amplifier – a precision error amplifier compares a fraction of VOUT (via internal resistor divider for fixed-output versions) with an internal bandgap reference (approximately 1.2V); the amplifier output drives the pass transistor gate; the +/-2% output accuracy is maintained over line, load, and temperature; (4) Power-Good Circuit – an internal comparator monitors VOUT; when VOUT exceeds approximately 92% of the nominal voltage, the PG open-drain output is released (goes high-impedance); an external capacitor on the PG delay pin sets the deglitch delay time; (5) Protection – internal current limit (approximately 300mA) protects against output short circuits; thermal shutdown disables the output when junction temperature exceeds approximately 160C; the device auto-recovers when the fault is removed.

• Automotive always-on: 12V battery to 5V MCU supply at 20mA continuous, 5uA IQ preserves battery during parking
• 24V truck system: regulate 24V battery to 5V for telematics ECU with 60V transient withstand
• Industrial backup: 48V UPS battery to 5V with PG output for system power sequencing Power tool BMS: 36V/48V Li-Ion pack to 5V for battery management IC