ST BAL-2690D3U User Manual
50 / 30+j25 balun transformer for 2.45 GHz ISM band
Features
■ 50 Ω nominal input / 30+j25 output differential
impedance
■ Low insertion loss
■ Low amplitude imbalance
■ Low phase imbalance
■ Small footprint: BAL-2690D3U < 1 mm²
Benefits
■ Very low profile (<700 µm)
■ High RF performances
■ RF BOM and area reduction
BAL-2690D3U
Flip-Chip
4 bumps
Figure 1. Top view
TopView
Applications
Balun transformer for applications such as:
■ Bluetooth STLC2690
■ Mobile phone
Description
The BAL-2690D3U is a balun designed to
transform single ended signals to differential
signals in Bluetooth applications.
The BAL-2690D3U has been customized for the
STLC2690 Bluetooth transceiver with 0.8 dB
insertion losses in the bandwidth
(2400 MHz - 2500 MHz) and with a specific
requirement for the S
The BAL-2690D3U has been designed using
STMicroelectronics IPD (integrated passive
device) technology on non conductive glass
substrate to optimize RF performances.
parameter.
CC22
GND
SE
Bump
A1
A2
B1
B2
A2
A2
B2
B2
Name
BALGND
BAL+
SE
A1
A1
Z
Z
C
C
B1
B1
Description
RF balanced ouput
Ground
RF balanced ouput
RF input
Figure 2. Application schematic
WLAN
PA
+ SP3T
2.4G
Antenna
Band
Pass
Filter
BT
Balun
BAL
BAL +
-
-
BT
RFIC
TM: IPAD is a trademark of STMicroelectronics.
February 2010 Doc ID 16056 Rev 2 1/8
www.st.com
8
Electrical characteristics BAL-2690D3U
1 Electrical characteristics
Table 1. Absolute maximum ratings (limiting values)
Symbol Test condition Min. Typ. Max. Unit
P
IN
Input power R
FIN
- - 20 dBm
ESD ratings MIL STD883G
V
(HBM: C = 100 pF, R = 1.5k , air discharge)
ESD ratings, machine model
ESD
(MM: C = 200 pF, R = 25 Ω L = 500 nH)
2000
500
--V
ESD ratings, charged device model (CDM)
(JESD22-C101D)
T
Table 2. Electrical characteristics (T
Operating temperature -40 - +85 °C
OP
= 25 °C) impedances
amb
500
Symbol Test condition Min. Typ. Max. Unit
Z
Z
Table 3. RF performance
Nominal differential output impedance - 30 + j25 - Ω
OUT
Nominal input impedance - 50 - Ω
IN
Symbol Test condition Min. Typ. Max. Unit
F Frequency range (bandwidth) 2402 2441 2480 MHz
I
Insertion loss in bandwidth - 0.8 1.1 dB
L
ripple Ripple in bandwidth - - 0.6 dB
R
Return loss in bandwidth 14 - - dB
L
Φ
A
R
CMRR
Phase imbalance -10 - 10 °
imb
Amplitude imbalance -1 - 1 dB
imb
Common mode rejection ratio (S
)20--dB
SC12
Magnitude for common
S
CC22
mode harmonic rejection
coefficient @ 2f
O
Phase for common mode
harmonic rejection
coefficient @ 2f
O
From 4804 MHz to
4960 MHz, 25 Ω is
considered as
reference for CM
0.7 - 1
-45 - 0
°
2/8 Doc ID 16056 Rev 2
BAL-2690D3U Electrical characteristics
Figure 3. Insertion loss (T
- 0.9
- 1.0
- 1.1
- 1.2
dB
m2
Ripple in band
0.02 dB typ.
= 25 °C) Figure 4. Return loss (T
amb
m1
dB
-10
-15
-20
amb
= 25 °C)
- 1.3
- 1.4
2.2E9
2.3E9
2.5E92.4E9
Figure 5. Amplitude imbalance (T
dB
1.0
0.5
0.0
-0.5
-1.0
2.2E9
2.3E9
Figure 7. S
1.0
0.9
magnitude @ 2f0
cc22
(T
= 25 °C)
amb
2.5E92.4E9
-25
F(Hz)
= 25 °C) Figure 6. Phase imbalance (T
amb
F(Hz)
-30
2.7E92.6E9
10
5
0.0
-5
-10
2.7E92.6E9
Figure 8. S
- 10
- 20
2.2E9
2.2E9
0
2.3E9
2.3E9
phase @2f0 (T
cc22
F(Hz)
2.5E92.4E9
= 25 °C)
amb
2.7E92.6E9
F(Hz)
2.5E92.4E9
= 25 °C)
amb
2.7E92.6E9
0.8
0.7
4.6E9
- 30
- 40
F(Hz)
- 50
5.2E95.0E94.9E94.8E94.7E9 5.1E9
4.6E9
F(Hz)
5.2E95.0E94.9E94.8E94.7E9 5.1E9
Doc ID 16056 Rev 2 3/8
Loading...