SLLSFW9A April 2024 – July 2024 ISO7741TA-Q1 , ISO7741TB-Q1
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
The minimum requirements for a suitable low dropout regulator are:
To determine VI for worst-case condition, the user must take the maximum values for VDO and VO specified in the LDO data sheet for rated output current (that is, 600mA) and add these values together. The user must also specify that the output voltage of the push-pull rectifier at the specified load current is equal or higher than VI-min. If the output voltage is not, the LDO loses line-regulation and any variations at the input passes straight through to the output. Hence, below VI-min the output voltage follows the input and the regulator behaves like a simple conductor.
with VIN-max as the maximum converter input voltage and n as the transformer turns ratio. Thus to prevent the LDO from damage the maximum regulator input voltage must be higher than VS-max. Table 8-3 lists the maximum secondary voltages for various turns ratios commonly applied in push-pull converters.
PUSH-PULL CONVERTER | LDO | |||
---|---|---|---|---|
CONFIGURATION | VIN-max [V] | TURNS-RATIO | VS-max [V] | VI-max [V] |
3.3VIN to 3.3VOUT | 3.6 | 1.5 ± 3% | 5.6 | 6 to 10 |
3.3VIN to 5VOUT | 3.6 | 2.2 ± 3% | 8.2 | 10 |
5VIN to 5VOUT | 5.5 | 1.5 ± 3% | 8.5 | 10 |