Datasheet

TPS51206

SLUSAH1A –MAY 2011–REVISED OCTOBER 2013

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DETAILED DESCRIPTION

VTT SINK/SOURCE REGULATOR

The TPS51206 is a sink/source tracking termination regulator specifically designed for low input voltage, low

cost, and low external component count systems where space is a key application parameter. The TPS51206

integrates a high-performance, low-dropout (LDO) linear regulator (VTT) that has ultimate fast response to track

½ VDDQSNS within 40 mV at all conditions, and its current capability is 2 A for both sink and source directions.

A 10-µF (or greater) ceramic capacitor(s) need to be attached close to the VTT terminal for stable operation; X5R

or better grade is recommended. To achieve tight regulation with minimum effect of trace resistance, the remote

sensing terminal, VTTSNS, should be connected to the positive terminal of the output capacitor(s) as a separate

trace from the high current path from the VTT pin.

The TPS51206 has a dedicated pin, VLDOIN, for VTT power supply to minimize the LDO power dissipation on

user application. The minimum VLDOIN voltage is 0.4 V above the ½ VDDQSNS voltage.

VTTREF

The VTTREF pin includes 10 mA of sink/source current capability, and tracks ½ of VDDQSNS with ±1%

accuracy. A 0.22-µF ceramic capacitor needs to be attached close to the VTTREF terminal for stable operation;

X5R or better grade is recommended.

POWER STATE CONTROL

The TPS51206 has two input pins, S3 and S5, to provide simple control of the power state. Table 1 describes

S3/S5 terminal logic state and corresponding state of VTTREF/VTT outputs. VTT is turn-off and placed to high

impedance (High-Z) state in S3. The VTT output is floated and does not sink or source current in this state.

When both S5 and S3 pins are LOW, the power state is set to S4/S5. In S4/S5 state, all the outputs are turn-off

and discharged to GND.

Table 1. S3 and S5 Control Table

STATE S3 S5 VTTREF VTT

S0 HI HI ON ON

S3 LO HI ON OFF(High-Z)

S4/S5 LO LO OFF(Discharge) OFF(Discharge)

VDD UNDERVOLTAGE LOCKOUT PROTECTION

The TPS51206 input voltage (VDD) includes undervoltage lockout protection (UVLO). When the VDD pin voltage

is lower than UVLO threshold voltage, VTT and VTTREF are shut off. This is non-latch protection.

OVER-TEMPERATURE PROTECTION

This device features internal temperature monitoring. If the temperature exceeds the threshold value, VTT and

VTTREF are shut off. This is a non-latch protection.

Product Folder Links: TPS51206