Datasheet
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APPLICATION INFORMATION
Minimum Load Requirements
Pin Functions
Enable ( EN)
Power-Good (PG) — TPS754xxQ
Sense (SENSE)
Feedback (FB)
Reset ( RESET) — TPS752xxQ
GND/HEATSINK
Input Capacitor
TPS752xxQ
TPS754xxQ
SLVS242C – MARCH 2000 – REVISED OCTOBER 2007
The TPS752xxQ and TPS754xxQ devices include four fixed-output voltage regulators (1.5 V, 1.8 V, 2.5 V and
3.3 V), and an adjustable regulator, the TPS75x01Q (adjustable from 1.5 V to 5 V).
The TPS752xxQ and TPS754xxQ families are stable even at zero load; no minimum load is required for
operation.
The EN terminal is an input that enables or shuts down the device. If EN is a logic high, the device is in
shutdown mode. When EN goes to logic low, then the device is enabled.
The PG terminal is an open drain, active high output that indicates the status of V
OUT
(output of the LDO). When
V
OUT
reaches 83% of the regulated voltage, PG goes to a high impedance state. It goes to a low-impedance
state when V
OUT
falls below 83% (that is, an overload condition) of the regulated voltage. The open drain output
of the PG terminal requires a pullup resistor.
The SENSE terminal of the fixed output options must be connected to the regulator output, and the connection
should be as short as possible. Internally, SENSE connects to a high-impedance wide-bandwidth amplifier
through a resistor-divider network, and noise pickup feeds through to the regulator output. It is essential to route
the SENSE connection in such a way to minimize/avoid noise pickup. Adding RC networks between the SENSE
terminal and V
OUT
to filter noise is not recommended because these types of networks may cause the regulator
to oscillate.
FB is an input terminal used for the adjustable-output options and must be connected to an external feedback
resistor divider. The FB connection should be as short as possible. It is essential to route it in such a way to
minimize/avoid noise pickup. Adding RC networks between FB terminal and V
OUT
to filter noise is not
recommended because these types of networks may cause the regulator to oscillate.
The RESET terminal is an open drain, active low output that indicates the status of V
OUT
. When V
OUT
reaches
95% of the regulated voltage, RESET goes to a high-impedance state after a 100-ms delay. RESET goes to a
low-impedance state when V
OUT
is below 95% of the regulated voltage. The open-drain output of the RESET
terminal requires a pullup resistor.
All GND/HEATSINK terminals are connected directly to the mount pad for thermal-enhanced operation. These
terminals could be connected to GND or left floating.
For a typical application, an input bypass capacitor (0.22 μ F to 1 μ F) is recommended for device stability. This
capacitor should be as close to the input pins as possible. For fast transient conditions where droop at the input
of the LDO may occur because of high inrush current, it is recommended to place a larger capacitor at the input
as well. The size of this capacitor depends on the output current and response time of the main power supply, as
well as the distance to the load (LDO).
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