Data Sheet

LT83203/LT83205

analog.com

Rev. B

33 of 44

As shown in Figure 55, capacitor DC bias characteristics tend to improve as component case size increases.

Figure 55. Capacitor Voltage Coefficient for Different Case Sizes

Larger case sizes are also beneficial for improved AC voltage characteristics. Capacitor values are often rated at 1VRMS

of AC voltage and can drop significantly when operating near 0VRMS, which is the operating condition of a bypass

capacitor.

As shown in Figure 56, larger case sizes tend to experience a smaller capacitance drop when operating near 0VRMS.

Therefore, an 0805 or larger ceramic capacitor should be used for the SET pin bypass capacitor for best performance.

A larger required capacitance value may require larger case sizes; for example, a 4.7μF value should use 1206 or

larger.

Table 7 shows some recommended SET pin capacitors.

Table 7. Suggested SET Capacitor Part Numbers

PART DESCRIPTION

MANUFACTURER/PART NUMBER

1µF, X7R, 35V, 0805

MURATA, GRM219R7YA105KA12

4.7µF, X7R, 50V, 1206

MURATA, GRM31CR71H475MA12

10µF, X7R, 100V, 1210

MURATA, GRM32EC72A106KE05

For high-vibration environments, non-piezoelectrically responsive capacitors should be used at the SET pin for

optimal performance. A piezoelectric ceramic capacitor generates voltage across its terminals due to mechanical

stress upon it, induced by mechanical vibrations or thermal transients. Film capacitors are the preferred option. If a

ceramic must be used, soft-termination ceramics are available, which reduce the sensitivity to the piezoelectric

effect.

DC BIAS (V)

1

5

15

10

20

25

–100

–80

–60

–40

–20

0

20

MURATA: 25V, 10%,

X7R, 10µF CERAMIC

GRM SERIES, 0805, 1.45mm THICK

GRM SERIES, 1206, 1.80mm THICK

GRM SERIES, 1210, 2.20mm THICK