TLV62080

SLVSAK9A

– OCTOBER 2011 – REVISED NOVEMBER 2011

www.ti.com

If the output voltage is not reached within the soft start time, such as in the case of heavy load, the converter will

enter regular operation. Consequently, the inductor current limit will operate as described below. The TLV62080

is able to start into a pre-biased output capacitor. The converter starts with the applied bias voltage and ramps

the output voltage to its nominal value.

POWER GOOD

The TLV62080 has a power good output going low when the output voltage is below its nominal value. The

power good keeps high impedance once the output is above 95% of the regulated voltage, and is driven to low

once the output voltage falls below typically 90% of the regulated voltage. The PG pin is a open drain output and

is specified to sink typically up to 0.5mA. The power good output requires a pull up resistor that is recommended

connecting to the device output. When the device is off due to disable, UVLO or thermal shutdown, the PG pin is

at high impedance.

The PG signal can be used for sequencing of multiple rails by connecting to the EN pin of other converters.

Leave the PG pin unconnected when not used.

UNDER VOLTAGE LOCKOUT

To avoid mis-operation of the device at low input voltages, an under voltage lockout is implemented, that shuts

THERMAL SHUTDOWN

temperature falls below the threshold the device returns to normal operation automatically.

INDUCTOR CURRENT LIMIT

The Inductor Current Limit prevents the device from high inductor current and drawing excessive current from the

battery or input voltage rail. Excessive current might occur with a shorted/saturated inductor or a heavy

load/shorted output circuit condition.

The incorporated inductor peak current limit measures the current during the high side and low side power

MOSFET on-phase in PWM mode. Once the high side switch current limit is tripped, the high side MOSFET is

turned off and the low side MOSFET is turned on to reduce the inductor current. Until the inductor current drops

down to low side switch current limit, the low side MOSFET is turned off and the high side switch is turned on

again. This operation repeats until the inductor current does not reach the high side switch current limit. Due to

the internal propagation delay, the real current limit value can exceed the static current limit in the electrical

characteristics table.

10

Submit Documentation Feedback

Copyright

© 2011, Texas Instruments Incorporated

Product Folder Link(s): TLV62080