LT5526 datasheet(13/16 Pages) LINER

13 / 16 page

LT5526

5526f

APPLICATIO S I FOR ATIO

Figure 12. Typical Return Loss Performance with

a 240MHz Narrowband Bridge IF Balun (Swept IF)

Figure 13. Typical Gain and IIP3 Performance with

a 240MHz Narrowband Bridge IF Balun (Swept IF)

IF+

C12

IFOUT

50Ω

L12

L11

C11

IF–

VCC

C13

C14

L14

OPT

L13

OPT

5526 F11

Figure 11. Narrowband Bridge IF Balun

•

Inductors L13 and L14 provide a DC path between VCC

and the IF+ pin. Only one of these inductors is required.

Low cost multilayer chip inductors are adequate for L11,

L12 and L13. If L14 is used instead of L13, a larger value

is usually required, which may require the use of a wire-

wound inductor. Capacitor C13 is a DC block which can

also be used to adjust the impedance match. Capacitor

C14 is a bypass capacitor.

Typical return loss of the IF output port is plotted versus

frequency in Figure 12 for a 240MHz balun design. For this

example, L11 = L12 = 100nH, C11 = C12 = 3.9pF, L14 =

560nH and C13 = 100pF. Performance versus IF output

frequency is shown in Figure 13 in the case of a 1900MHz

RF input. These results show that the usable IF bandwidth

is greater than 60MHz, assuming tight tolerance matching

components. Contact the factory for applications assis-

tance with this circuit.

FREQUENCY (MHz)

100

–25

–20

–15

–10

–5

150

200

250

300

5526 F12

350

400

IF FREQUENCY (MHz)

190

270

5526 F13

–5

210

IIP3

GAIN

230

250

290

TA = 25°C

fRF = 1900MHz

fLO = fRF – fIF

PLO = –5dBm

LT5526 Datasheet(PDF) 13 Page - Linear Technology

LT5526 Datasheet(HTML) 13 Page - Linear Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Datasheet Download

Link URL