All trademarks are the property of their respective owners.
DescriptionThe TPS40195RGYT is a flexible synchronous buck controller that operates from a nominal 4.5-Vto 20-V supply. This controller implements voltage mode control with the switching frequencyadjustable from 100 kHz to 600 kHz. Flexible features found on this device include selectablesoft-start time, programmable short-circuit limit, programmable undervoltage lockout (UVLO) andsynchronization capability. An adaptive anti-cross conduction scheme is used to prevent shootthrough current in the power FETs. Overcurrent detection is done by sensing the voltage drop acrossthe low-side MOSFET when it is on, and comparing it with a user-programmable threshold.
The threshold is set with a single external resistor connected from ILIM to GND.Pulse-by-pulse limiting (to prevent current runaway) is provided by sensing the voltage across thehigh-side MOSFET when it is on and terminating the cycle when the voltage drop rises above a fixedthreshold of 550 mV. When the controller senses an output short circuit, both MOSFETs are turnedoff and a timeout period is observed before attempting to restart. This provides limited powerdissipation in the event of a sustained fault. Synchronization on this device is bi-directional.Devices can be synchronized 180° out of phase to a chosen master TPS40195RGYT running at a fixed 250kHz or 500 kHz, or can be synchronized to an outside clock source anywhere in the 100 kHz to 600kHz range.
Feature
- Input Operating Voltage Range: 4.5 V to 20 V
- Output Voltage as Low as 0.591 V ±0.5%
- 180° Bi-Directional Out-of-Phase Synchronization
- Internal 5-V Regulator
- High and Low MOSFET Sense Overcurrent
- 100-kHz to 600-kHz Switching Frequency
- Enable and Power Good
- Programmable UVLO and Hysteresis
- Thermal Shutdown at 150°C
- Selectable Soft Start
- Prebias Output Safe
All trademarks are the property of their respective owners.
DescriptionThe TPS40195 is a flexible synchronous buck controller that operates from a nominal 4.5-Vto 20-V supply. This controller implements voltage mode control with the switching frequencyadjustable from 100 kHz to 600 kHz. Flexible features found on this device include selectablesoft-start time, programmable short-circuit limit, programmable undervoltage lockout (UVLO) andsynchronization capability. An adaptive anti-cross conduction scheme is used to prevent shootthrough current in the power FETs. Overcurrent detection is done by sensing the voltage drop acrossthe low-side MOSFET when it is on, and comparing it with a user-programmable threshold.
The threshold is set with a single external resistor connected from ILIM to GND.Pulse-by-pulse limiting (to prevent current runaway) is provided by sensing the voltage across thehigh-side MOSFET when it is on and terminating the cycle when the voltage drop rises above a fixedthreshold of 550 mV. When the controller senses an output short circuit, both MOSFETs are turnedoff and a timeout period is observed before attempting to restart. This provides limited powerdissipation in the event of a sustained fault. Synchronization on this device is bi-directional.Devices can be synchronized 180° out of phase to a chosen master TPS40195 running at a fixed 250kHz or 500 kHz, or can be synchronized to an outside clock source anywhere in the 100 kHz to 600kHz range.
