ZHCSU10P March 2000 – February 2025 LP2981-N
PRODUCTION DATA
The LP2981-N is shut off by pulling the ON/OFF input low, and turned on by driving the input high. If this feature is not to be used, the ON/OFF input is required to be tied to VIN to keep the regulator on at all times (the ON/OFF input must not be left floating).
For proper operation of the LDO, the signal source used to drive the ON/OFF input must be able to swing above and below the specified turnon/turnoff voltage thresholds which specify an ON or OFF state (see Electrical Characteristics).
The ON/OFF signal can come from either a totem-pole output, or an open-collector output with pullup resistor to the LP2981-N input voltage or another logic supply. The high-level voltage can exceed the LP2981-N input voltage, but must remain within the Absolute Maximum Ratings for the ON/OFF pin.
For the legacy chip only, the turnon and turnoff voltage signals applied to the ON/OFF input must have a slew rate greater than 40mV/μs.