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http://www.union-ic.com

Rev.04 Jul.2012

6/11

UM4601/4611/8601/8611

Ground Connection Recommendation

Parasitic inductance (L) present in the board layout will affect the filtering performance of the

device. As frequency (f) increases, the effect of the inductance becomes more dominant. This

effect is given by Equation 1.

Pin

Identification

1 - 4

Input Lines

5 - 8

Output Lines

Center Tab

Ground

Pin Identification & Configuration

UM4601/UM4611

Equation 1: The Impedance of an Inductor at

Frequency XLF

XLF(L,f ) = 2×л×f ×L

Where:

L= Inductance (H)

f = Frequency (Hz)

Pin

Identification

1 - 8

Input Lines

9 - 16

Output Lines

Center Tab

Ground

Pin Identification & Configuration

UM8601/UM8611

Equation 1: The Impedance of an Inductor at

Frequency XLF

XLF(L, f ) = 2×л×f ×L

Where:

L= parasitic inductance in the PCB (H)

f = Frequency (Hz)