LM2742MTC National Semiconductor, LM2742MTC Datasheet - Page 15

• Manufacturer Part Number: LM2742MTC
• Manufacturer: National Semiconductor

Specifications of LM2742MTC

• Lead Free Status / RoHS Status: Not Compliant

The example circuit of Figure 5 has been designed for mini-
mum component count and overall solution size. A switching
frequency of 600kHz allows the use of small input/output ca-
pacitors and a small inductor. The availability of separate 5V
and 12V supplies (such as those available from desk-top
computer supplies) and the low current further reduce com-
The circuit of Figure 6 demonstrates the LM2742 delivering a
low output voltage at high efficiency (87%). A separate 5V
FIGURE 6. 3.3V to 0.8V, 5A, 500kHz
FIGURE 5. 5V to 1.8V, 3A, 600kHz
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ponent count. Using the 12V supply to power the MOSFET
drivers eliminates the bootstrap diode, D1. At low currents,
smaller FETs or dual FETs are often the most efficient solu-
tions. Here, the Si4826DY, an asymmetric dual FET in an
SO-8 package, yields 92% efficiency at a load of 2A.
supply is required to run the chip, however the input voltage
can be as low as 2.2
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