ZHCSN49N January 2007 – June 2024
PRODUCTION DATA
The TPS748 was designed to have excellent transient response for most applications with a small amount of output capacitance. In some cases, the transient response can be limited by the transient response of the input supply. This limitation is especially true in applications where the difference between the input and output is less than 300 mV. In this case, adding additional input capacitance improves the transient response much more than just adding additional output capacitance does. With a solid input supply, adding additional output capacitance reduces undershoot and overshoot during a transient event; see Figure 5-37 in the Typical Characteristics section. Because the TPS748 is stable with output capacitors as low as 2.2 μF, many applications can then need very little capacitance at the LDO output. For these applications, local bypass capacitance for the powered device can be sufficient to meet the transient requirements of the application. This design reduces the total solution cost by avoiding the need to use expensive, high-value capacitors at the LDO output.