Texas Instruments’ TPS40100 is a synchronous dc-dc buck controller with innovative sequencing and output voltage margining features. Capable of operating from a 4.5-V to 18-V input range, the device operates at an adjustable (100-kHz to 600-kHz) switching frequency. The controller will be incorporated into future POLA plug-in power modules.
The TPS40100 controller seamlessly supports three common sequencing schemes found in high-performance power systems. These include sequential sequencing, ratio-metric sequencing and simultaneous sequencing. Using the device’s power good function, the TPS40100 can implement a sequential sequencing scheme where a single power supply output voltage will ramp up and settle at its final regulation voltage before the next power supply voltage ramps up.
By using a soft-start capacitor, the TPS40100 is able to implement a ratio-metric scheme that proportionally ramps up both power supply outputs at the same time until proper regulation is reached. Finally, the device can effectively implement a simultaneous sequencing scheme through its integrated amplifier. In addition, the TPS40100 incorporates a simple margining control function. Two digital input pins allows the user to margin up or margin down the power supply by ±5% or ±3%.
The TPS40100 efficiently manages power supplies up to 15 A with peak efficiencies of 90%. In addition, the synchronous peak current-mode controller with on-chip adaptive gate drive provides a peak current mode control loop, which allows simple compensation insensitive to wide variations of output capacitance. For improved load regulation, separate power ground and signal ground pins provide high accuracy remote load sensing.
The device also is equipped with all supervisory and control features for today’s power supplies, including pre-bias startup capability, programmable undervoltage lockout, lossless DCR current sensing, power good indicator, synchronization input, programmable overcurrent protection and thermal shutdown. Packaged in a 24-pin QFN, the TPS40100 is priced at $1.45 each in quantities of 1000 units.
