The TPS2480/81 are designed to minimize inrush into applications and protect both the load and the FET from over-current or short circuit events. They control an external N-channel MOSFET switch and provide accurate voltage, current, and power monitoring using a configurable 12 bit A/D converter via an I2C interface. The independently adjustable power limit and current limit ensure that the external MOSFET operates within the FET’s Safe Operating Area (SOA).
The flexible design includes a Power Good output which can be used for sequencing as well as load fault indication. An external timer capacitor can set the fault time to help immunize the system from nuisance shutdowns during brief transient events.
The monitoring circuitry incorporates a high accuracy A/D converter which can be configured from a 9 to 13 bit converter. The internal gain of the A/D can be configured to scale the current, voltage and power readings to the needs of the application. An additional multiplying register calculates power in Watts. The I2C interface uses multi-level addressing to allow up to 16 programmable addresses.
The TPS2480 and TPS2481 monitors shunts on buses that can vary from 9 V to 26 V and with a few external components it is possible to monitor buses as high as 80 V.
The monitoring circuitry uses a single 3-V to 5.5-V supply, drawing a maximum of 1 mA of supply current.
Programmable FET Power Limit
External N-Channel FET Gate Drive
Programmable Fault Timer
Open Drain Power Good Output
I2C monitoring of Current, Voltage and Power
High Accuracy Current Monitoring (1% over temperature)