LM2611 Datasheet | National Semiconductor

Description The LM2611 is a current mode, PWM inverting switching regulator. Operating from a 2.7 - 14V supply, it is capable of producing a regulated negative output voltage of up to - (36-VIN(MAX)). The LM2611 utilizes an input and output inductor, which enables low voltage ripple and RMS current on both the input and the output. With a switching frequency of 1.4MHz, the inductors and output capacitor can be physically small and low cost. High efficiency is achieved through the use of a low RDS(ON) FET. The LM2611 features a shutdown pin, which can be activated when the part is not needed to lower the Iq and save battery life. A negative feedback (NFB) pin provides a simple method of setting the output voltage, using just two resistors. Cycle-by-cycle current limiting and internal pensation further simplify the use of the LM2611. The LM2611 is available is a small SOT23-5 package. It es in two grades: Grade A Current Limit RDS(ON) 1.2A 0.5Ω Grade B 0.9A 0.7Ω Features n n n n n n n n n 1.4MHz switching frequency Low RDS(ON) DMOS FET 1m Vp-p output ripple - 5V at 300m A from 5V input Better regulation than a charge pump Uses tiny capacitors and inductors Wide input range: 2.7V to 14V Low shutdown current: < 1u A 5-lead SOT-23 package Applications n n n n n MR Head Bias Digital camera CCD bias LCD bias Ga As FET bias Positive to negative conversion Typical Application Circuit © 2002 National Semiconductor Corporation DS200181 .national. Connection Diagram Top View 5-lead SOT-23 Package NS Package Number MF05A Ordering Information Order Number LM2611AMF LM2611AMFX LM2611BMF LM2611BMFX SOT23-5 MF05A Package Type NSC Package Drawing Supplied As 1K Tape and Reel 3K Tape and Reel 1K Tape and Reel 3K Tape and Reel Package ID S40A S40A S40B S40B Pin Description Pin 1 2 3 4 5 Name SW GND NFB SHDN VIN Analog and power ground. Negative feedback. Connect to output via external resistor divider to set output voltage. Shutdown control input. VIN =...