text.skipToContent text.skipToNavigation


Negative Low Dropout Adjustable Regulator

Availability: 5,486


Package | PIN: TO-220 (KC) | 5
Temp: Q (-40 to 125)
Carrier: Partial Tube
Qty Price
1-9 $3.09
10-24 $2.78
25-99 $2.59
100-249 $2.27
250-499 $2.13
500-749 $1.81
750-999 $1.52
1000+ $1.46


  • Output Voltage Adjustable from −3 V to −24 V, Typically −2 V to −25 V
  • Output Current in Excess of 1 A
  • Dropout Voltage Typically 0.6 V at 1-A Load
  • Low Quiescent Current
  • Internal Short Circuit Current Limit
  • Internal Thermal Shutdown With Hysteresis
  • TTL, CMOS Compatible ON/OFF Switch
  • Functional Complement to the LM2941 Series

All trademarks are the property of their respective owners.

Texas Instruments  LM2991T/NOPB

The LM2991 is a low dropout adjustable negative regulator with a output voltage rangebetween −3 V to −24 V. The LM2991 provides up to 1 A of load current and features aON /OFF pin for remote shutdown capability.

The LM2991 uses new circuit design techniques to provide a low dropout voltage, lowquiescent current and low temperature coefficient precision reference. The dropout voltage at 1-Aload current is typically 0.6 V and an ensured worst-case maximum of 1 V over the entire operatingtemperature range. The quiescent current is typically 1 mA with a 1-A load current and aninput-output voltage differential greater than 3 V. A unique circuit design of the internal biassupply limits the quiescent current to only 9 mA (typical) when the regulator is in the dropoutmode (VOUT − VIN ≤ 3 V).

The LM2991 is short-circuit proof, and thermal shutdown includes hysteresis to enhancethe reliability of the device when inadvertently overloaded for extended periods. The LM2991 isavailable in 5-lead TO-220 and DDPAK/TO-263 packages and is rated for operation over the automotivetemperature range of −40°C to +125°C. Mil-Aero versions are also available.