CHM2378a
Ref. : DSCHM23781269 -26-Sep.-01
1/
8
Specifications subject to change without notice
United Monolithic Semiconductors S.A.S.
Route Dpartementale 128 - B.P.46 - 91401 Orsay Cedex France
Tel. : +33 (0)1 69 33 03 08 - Fax : +33 (0)1 69 33 03 09
W-band Dual Channel Mixer
GaAs Monolithic Microwave IC
Description
The CHM2378 is a dual channel mixer.
Each mixer cell is a balanced structure
based on a six quarter wave ring. The non-
linear devices are high quality Schottky
diodes providing low conversion loss and
very low 1/f noise.
This circuit is manufactured with the BES-
MMIC process: 1 m Schottky diode
device, air bridges, via holes through the
substrate, stepper lithography.
It is available in chip form.
Main Features
n
W-band LO and RF frequency range
n
Low conversion loss
n
IF from DC to 100MHz
n
High LO/RF isolation
n
High LO/AM noise rejection
n
Very low 1/f noise
n
Low LO input power
n
Automatic assembly oriented
n
Chip size: 1.98 x 2.07 x 0.10 mm
RF1
IF2
IF1
RF2
LO
Dual channel mixer block diagram
-15
-14
-13
-12
-11
-10
-9
-8
-7
-6
-5
75
75,5
76
76,5
77
77,5
78
LO frequency (GHz)
C
o
nv
ers
i
o
n g
a
i
n
(
d
B)
Typical conversion characteristic
LO power = 8dBm ; IF=10MHz
(measurement in test fixture)
Main Characteristics
Tamb. = 25C
Symbol Parameter Min
Typ
Max
Unit
F_lo, F_rf
LO,RF frequency
76
76.5
77
GHz
F_if
IF frequency range
DC-100
MHz
Lc Conversion
loss
7.5 9.5 dB
I_lo/rf LO/RF
isolation
25
dB
N_if
IF noise @ 100kHz
-162
dBm/Hz
ESD Protection : Electrostatic discharge sensitive device. Observe handling precautions !
CHM2378a
W-band Dual Channel Mixer
Ref. DSCHM23781269 -26-Sep.-01
2/
8
Specifications subject to change without notice
Route Dpartementale 128 , B.P.46 - 91401 ORSAY Cedex - FRANCE
Tel.: +33 (0)1 69 33 03 08 - Fax : +33 (0)1 69 33 03 09
Electrical Characteristics
Full operating temperature range, used according to section "Typical assembly and bias
configuration"
Symbol Parameter
Min
Typ
Max
Unit
F_lo, F_rf
LO,RF frequency
76
77
GHz
F_if
IF frequency range
DC-100
MHz
Lc Conversion
loss
4.5 7.5 9.5 dB
|(d(
Lc)/dT)*
T| Conversion loss difference from
chip to chip versus temperature
0.3
(to be confirmed)
dB
P_lo
LO input power
4
7
11
dBm
P_RF_1dB
RF input power at 1 dB
-3
0
dBm
VSWR_lo
LO port VSWR (50
)
2:1
2.5:1
VSWR_rf
RF port VSWR (50
)
2:1
2.5:1
IMP_if
IF load impedance (1)
200
I_lo/rf LO/RF
isolation
20 25 dB
I_rf1/rf2
Isolation between RF channels
25
30
dB
I_rfi/rfj
Isolation between RF and IF
channels
25 30 dB
R_lo_am
LO AM noise rejection (SSB)
25
30
dB
Noise figure for IF=1kHz (2)
34
39
dB
Noise figure for IF=10kHz (2)
28
33
dB
Noise figure for IF=100kHz (2)
20.5
25.5
dB
NF
Noise figure for IF=200kHz (2)
17
22
dB
+V
Positive supply voltage (3)
4.5
V
+I
Positive supply current (3)
1.5
2.5
mA
Top
Operating temperature range
-40
+100
C
(1) The IF optimum load for conversion loss is 200
. For minimum noise figure this load can be lower,
the best results have been obtained on 50
.
(2) Measured on 200
IF impedance.
(3) An external resistor controls the bias current (see section "Typical Assembly and Bias
Configuration")
W-band Dual Channel Mixer
CHM2378a
Ref. DSCHM23781269 -26-Sep.-01
3/
8
Specifications subject to change without notice
Route Dpartementale 128 , B.P.46 - 91401 ORSAY Cedex - FRANCE
Tel.: +33 (0)1 69 33 03 08 - Fax : +33 (0)1 69 33 03 09
Absolute Maximum Ratings (1)
Symbol Parameter Values
Unit
+V Supply
voltage
6
V
+I
Supply current (for one input)
2.5
mA
P_lo
Maximum peak input power overdrive at LO port (2)
12
dBm
P_rf_cw
Maximum input power at RF port (3)
3
dBm
Tstg
Storage temperature range
-55 to +125
C
(1) Operation of this device above anyone of these parameters may cause permanent damage.
(2) Duration < 1s
(3) Continuous wave mode.
CHM2378a
W-band Dual Channel Mixer
Ref. DSCHM23781269 -26-Sep.-01
4/
8
Specifications subject to change without notice
Route Dpartementale 128 , B.P.46 - 91401 ORSAY Cedex - FRANCE
Tel.: +33 (0)1 69 33 03 08 - Fax : +33 (0)1 69 33 03 09
Chip Mechanical Data and Pin References
1
2
3
4
5
6
7
8
9
10
11
12
13
14
19 18 17 16 15
Unit = m
External chip size (including dicing streets) = 1980 x 2070
35
Chip thickness = 100 +/- 10
HF Pads (2,10,13) = 68 x 118
DC/IF Pads = 100 x 100
Pin number
Pin name
Description
1,3,9,11,12,14
Ground : should not be bonded. If required,
please ask for more information.
6,17
Ground (optional)
7,16
Not Connected
2 LO
LO input
4 +V1
Positive supply voltage 1
5 C1
Bias 1 decoupling
8 IF1
First IF output
10 RF1
First RF input
13 RF2
Second RF input
15 IF2
Second IF output
18 C2
Bias 2 decoupling
19 +V2
Positive supply voltage 2
W-band Dual Channel Mixer
CHM2378a
Ref. DSCHM23781269 -26-Sep.-01
5/
8
Specifications subject to change without notice
Route Dpartementale 128 , B.P.46 - 91401 ORSAY Cedex - FRANCE
Tel.: +33 (0)1 69 33 03 08 - Fax : +33 (0)1 69 33 03 09
External components for bias and IF
Several external configurations are possible for bias and IF. The objective is to give flexibility
for the integration.
As this component is mainly dedicated to low IF use, there are several possibilities for
interfacing with low noise IF amplifier. The optimum IF load for conversion loss is 200
,
however the best results on noise figure have been obtained on 50
. Depending on the IF
amplifier noise characteristic this load can be modified in order to optimise the noise figure..
A series capacitor, between IF output and the load is recommended.
Due to high sensitivity to electrical discharges an integrated resistance is used and two ports
are available for biasing each mixer. One is for the connection of a decoupling capacitor (C1,
C2) and the other one is for the supply voltage connection through an external series
resistance (+V1, +V2). However, if necessary only the "C1, C2" ports can be used.
RF1
RF2
LO
1k
IF2
V2
C2
1k
IF1
V1
C1
Block diagram of the MMIC
RF1
RF2
LO
+V
1k
V2
C2
1k
IF1
V1
C1
R_bias
R_load_IF
+V
R_bias
C_IF
IF2
R_load_IF
C_IF
Recommended IF/DC external configuration
The recommended values for external components are:
C1,C2
R_bias_t*C >> 1/F_if
R_bias_t
2.5k
for 1.5mA current consumption (V = 4.5V, typical LO
power)
R_load_if
From 50 to 200
Notes::
1. R_bias_t = R_bias + 1k
when V1 and V2 ports are used.
2. R_bias_t can be adjusted if necessary; This allows to optimise the performances when some
parameters are different from recommended (Supply voltage, LO power ...). However
maximum ratings for the current have to be taken into account.
3. A series capacitor at IF outputs is recommended for DC decoupling.
PDF 
ZIP