LM2781

If Military/Aerospace specified devices are required,please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.
V_IN pin: Voltage to GND ..........................−0.3V to 5.8V
SD pin: Voltage to GND .........-0.3V to(V_IN + 0.3V), with
........................................................................5.8V max
Output Short-to-GND Duration
(Note 3) .................................................................1 sec.
Maximum Junction Temperature
(T_J-MAX) ...............................................................150°C
Storage Temperature Range............. -65°C to +150°C
Pad Temperature
(Soldering, 10 sec.) .............................................265°C
ESD Rating (Note 4)
Human-body model ..................................................2KV
Machine model......................................................200KV

The LM2781 is a charge pump that inverts an input voltage in the range of 1.8V to 5.5V to the corresponding output voltage of -1.8V to -5.5V. With use of three or four low-cost external ceramic capacitors, the LM2781 can provide up to
50mA of output current.

The LM2781 operates at a 210kHz typical switching frequency to minimize supply current (0.7mA typ.). Two charge pumps operate 180° out of phase to significantly reduce the output voltage ripple compared to that of traditional singlephase charge pump circuits. If larger output ripple can be tolerated, optional capacitor C2 may be omitted to reduce the cost and size of the solution. The LM2781 is available in an 8-pin Micro SMD chip-scale package.

See also: LM2780, a slow clock (12kHz typ) version of this topology with extremely low supply current.