LM339DR Datasheet

LM139-N , LM239-N , LM2901-N , LM3302-N , LM339-N
www.ti.com SNOSBJ3E –NOVEMBER 1999–REVISED DECEMBER 2014
9 Power Supply Recommendations
Even in low-frequency applications, the LM139-N can have internal transients which are extremely quick. For this
reason, bypassing the power supply with 1.0 µF to ground will provide improved performance; the supply bypass
capacitor should be placed as close as possible to the supply pin and have a solid connection to ground. The
bypass capacitors should have a low ESR.
10 Layout
10.1 Layout Guidelines
Try to minimize parasitic impedances on the inputs to avoid oscillation. Any positive feedback used as hysteresis
should place the feedback components as close as possible to the input pins. Take care to ensure that the
output pins do not couple to the inputs. This can occur through capacitive coupling if the traces are too close and
lead to oscillations on the output.
The optimum bypass capacitor placement is closest to the V+ and ground pins. Take care to minimize the loop
area formed by the bypass capacitor connection between V+ and ground. The ground pin should be connected
to the PCB ground plane at the pin of the device. The feedback components should be placed as close to the
device as possible minimizing strays.
10.2 Layout Example
Figure 38. Layout Example
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Product Folder Links: LM139-N LM239-N LM2901-N LM3302-N LM339-N