Available on Tape

and Reel for Pick and

Place Manufacturing.

USA/Canada:

Toll Free:

Europe

:

(315) 432-8909

(800) 411-6596

+44 2392-232392

Model BD2425NCSR

Rev C

Ultra Low Profile 0404 Balun for the

Cambridge Silicon Radio M1824 UNIFI-1 Chipset

Description

The BD2425NCSR is a low cost, low profile sub-miniature unbalanced to

balanced transformer designed specifically for Cambridge Silicon Radio’s UNITI-1

WiFi chipset. The BD2425NCSR is ideal for high volume manufacturing and delivers

higher performance than traditional ceramic baluns. The BD2425NCSR matched

exactly to the differential port impedances of the UNIFI-1 device. The BD2425NCSR

enables single ended signals to be applied to differential ports of this Cambridge

Silicon Radio chipsets. The output ports have equal amplitude (-3dB) with 180

degree phase differential. The BD2425NCSR is available on tape and reel for pick

and place high volume manufacturing.

ROOM (25°°°°C)

Parameter

Min.

Typ.

Max

Unit

Frequency

2400

2500

MHz

Unbalanced Port Impedance

50

Balanced Port Impedance

Matched

Return Loss

10

15

dB

Insertion Loss*

0.35

1.0

dB

Amplitude Balance

0.2

0.5

Phase Balance

2

4

CMRR

35

Power Handling

1

Watts

Features:

• 2400 – 2500 MHz

• 0.56 mm Height Profile

• Matched for CSR’s UNIFI-1

• Low Insertion Loss

• Surface Mountable

• Tape & Reel

• Non-conductive

• RoHS Compliant

• Halogen free

Operating Temperature

-55

+85

ºC

* Insertion Loss stated at room temperature (Insertion Loss is approximately 0.1 dB higher at +85 ºC)

** Stated performance is based on the proper matching network described in the data sheet

Outline Drawing

Mechanical Outline

Dimensions are in Inches [Millimeters]

Tolerances are Non-Cumulative

Bottom View (Far-side)

Side View

Top View (Near-side)

Unbalanced Port

GND / DC Feed

+ RF GND

4

3

Designation

Pin

1

2

1

2

3

4

Balanced Port

.020 [0.51]

.020 [0.51]

3x.010

[0.25]

3x.010

[0.25]

Balanced Port

.012 [0.30]

.012 [0.30]