19-1627; Rev 3; 6/05
DBS Direct Downconverter
General Description
The MAX2106 low-cost, direct-conversion tuner IC is
designed for use in digital direct-broadcast satellite
(DBS) television set-top box units and is a pin-for-pin
upgrade for the MAX2104. Its direct-conversion archi-
tecture reduces system cost compared to devices with
IF-based architectures. The MAX2106 directly tunes L-
band signals to baseband using a broadband I/Q
downconverter. The operating frequency range spans
925MHz to 2175MHz.
The IC includes a low-noise amplifier (LNA) with gain
control, I and Q downconverting mixers, lowpass filters
with gain and frequency control, a local oscillator (LO)
buffer with a 90° quadrature network, and a charge-
pump-based phase-locked loop (PLL) for frequency
control. The MAX2106 has an on-chip LO, requiring
only an external varactor-tuned LC tank for operation.
The LO’s output drives the internal quadrature genera-
tor and has a buffer amplifier to drive off-chip circuitry.
The MAX2106 comes in a 48-pin thin quad flat-pack
package with exposed paddle (EP).
Advantages Over MAX2104
o
Improved Front End Achieves 10.2dB NF at 1550MHz
o
Higher Input IIP3: 11.5dBm at 1550MHz
o
Reduced Spurious Downconversion Products
o
Capable of Using an External Synthesizer
MAX2106
Features
o
Drop-In Replacement for MAX2104 Designs
Requires Only Minor Software Upgrade and
Two External Resistor Value Changes
o
Complete Low-Cost Solution for DBS Direct
Downconversion
o
High Level of Integration Minimizes Component
Count
o
1MBaud to 45MBaud Operation
o
Selectable LO Buffer
o
+5V Single-Supply Operation
o
925MHz to 2175MHz Input Frequency Range
o
On-Chip Quadrature Generator, Dual-Modulus
Prescaler (/32, /33)
o
On-Chip Crystal Oscillator Amplifier
o
PLL Phase Detector with Gain-Controlled Charge
Pump
o
Input Levels: -25dBm to -68dBm per Carrier
o
Over 50dB Gain Control Range
o
Noise Figure = 10.2dB; IIP3 = +11.5dBm
(at 1550MHz)
o
Automatic Baseband Offset Correction
Applications
U.S. DSS Set-Top Receivers
European DVB-Compliant
Systems
Cellular Base Stations
Wireless Local Loop
Broadband Systems
LMDS
Professional Receivers
VSAT
Microwave Links
Pin Configuration
TOP VIEW
FB
GND
V
CC
TANK+
VRLO
TANK-
GND
GND
V
CC
LOBUF-/TPSOUT-
LOBUF+/FPSOUT+
47
46
45
44
43
42
41
40
39
38
37
48
CP
V
CC
CFLT
XTL-
XTL+
GND
V
CC
RFIN-
RFIN+
GND
GND
QDC-
QDC+
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
36
35
34
33
32
31
30
29
28
27
26
25
MAX2106
PLLIN-
PLLIN+
MOD-
MOD+
LODIVSEL
IOUT+
IOUT-
V
CC
QOUT+
QOUT-
RFBAND
FLCLK
Ordering Information
PART
MAX2106UCM
TEMP RANGE
0°C to +85°C
PIN-PACKAGE
48 TQFP-EP*
48 TQFP-EP*
MAX2106UCM+
0°C to +85°C
*EP =
Exposed paddle.
+Denotes
lead-free package.
Functional Diagram appears at end of data sheet.
IDC-
IDC+
LOBUFSEL
GND
RFOUT
CPG1
V
CC
XTLOUT
CPG2
GC1
TQFP
________________________________________________________________
Maxim Integrated Products
GC2
INSEL
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
DBS Direct Downconverter
MAX2106
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ..............................................................-0.3V to +7V
All Other Pins to GND................................-0.3V to (V
CC
+ 0.3V)
RFIN+ to RFIN-, TANK+ to TANK-,
IDC+ to IDC-, QDC+ to QDC- .........................................±2V
IOUT_, QOUT_ to GND Short-Circuit Duration .......................10s
LOBUF+/PSOUT+, LOBUF-/PSOUT- Short-Circuit Duration..10s
Continuous Current (any pin other than V
CC
or GND)........20mA
Continuous Power Dissipation (T
A
= +70°C)
48-Pin TQFP-EP (derate 27mW/°C above +70°C) ..........1.5W
Operating Temperature ..........................................0°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(V
CC
= +4.75V to +5.25V, V
FB
= +2.4V, C
IOUT_
= C
QOUT_
= 10pF, ƒ
FLCLK
= 2MHz, RFIN_ = unconnected, R
IOUT_
= R
QOUT_
= 10kΩ,
V
LOBUFSEL
= 0.5V, V
RFBAND
= V
INSEL
= V
CPG1
= V
CPG2
= +2.4V, V
PLLIN+
= V
MOD+
= +1.3V, V
PLLIN-
= V
MOD-
= +1.1V, T
A
= +25°C,
unless otherwise noted. Typical values are at V
CC
= +5V, unless otherwise noted.)
PARAMETER
Operating Supply Voltage
Operating Supply Current
Input Voltage High
Input Voltage Low
Input Current
RFBAND Input Current
SLEW-RATE-LIMITED DIGITAL INPUT
(f
LCLK
)
FLCLK Input Voltage High
FLCLK Input Voltage Low
FLCLK Input Current (Note 1)
Common-Mode Input Voltage
Input Voltage Low
Input Voltage High
Input Current (Note 1)
DIFFERENTIAL DIGITAL OUTPUTS
(LOBUF+/PSOUT+, LOBUF-/PSOUT-)
Common-Mode Output Voltage
Output Voltage Low (Note 2)
Output Voltage High (Note 2)
FREQUENCY SYNTHESIZER/LO BUFFER
(V
MOD+
- V
MOD-
)
≥
200mV, LOBUFSEL
≤
0.5V
Prescaler Ratio
(V
MOD+
- V
MOD-
)
≤
-200mV, LOBUFSEL
≤
0.5V
LOBUFSEL
≥
2.4V, LODIVSEL
≤
0.5V
LOBUFSEL
≥
2.4V, LODIVSEL
≥
2.4V
Reference Divider Ratio
XTLOUT Output DC Voltage
V
CPG1
≤
0.5V, V
CPG2
≤
0.5V
Charge-Pump Output High
Measured at FB
V
CPG1
≤
0.5V, V
CPG2
≥
2.4V
V
CPG1
≥
2.4V, V
CPG2
≤
0.5V
V
CPG1
≥
2.4V, V
CPG2
≥
2.4V
2
0.08
0.24
0.48
1.44
32
33
2
1
8
1.9
0.1
0.3
0.6
1.8
0.12
0.36
0.72
2.16
mA
32
33
2
1
8
V
V
CMO
Referenced to V
CMO
, LOBUFSEL
≤
0.5V
Referenced to V
CMO
, LOBUFSEL
≤
0.5V
150
2.16
2.4
2.64
-150
V
mV
mV
V
CMI
Referenced to V
CMI
Referenced to V
CMI
100
-5
5
R
SOURCE
= 50kΩ, V
FLCLK
= 1.65V
-1
1.08
1.2
DIFFERENTIAL DIGITAL INPUTS
(MOD+, MOD-, PLLIN+, PLLIN-)
1.32
-100
V
mV
mV
µA
1.85
1.45
1
V
V
µA
SYMBOL
V
CC
I
CC
V
IH
V
IL
I
IN
-15
-200
2.4
0.5
10
200
CONDITIONS
MIN
4.75
195
TYP
MAX
5.25
275
UNITS
V
mA
V
V
µA
µA
STANDARD DIGITAL INPUTS
(INSEL, CPG1, CPG2, LOBUFSEL, LODIVSEL)
_______________________________________________________________________________________
DBS Direct Downconverter
DC ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +4.75V to +5.25V, V
FB
= +2.4V, C
IOUT_
= C
QOUT_
= 10pF, ƒ
FLCLK
= 2MHz, RFIN_ = unconnected, R
IOUT_
= R
QOUT_
= 10kΩ,
V
LOBUFSEL
= 0.5V, V
RFBAND
= V
INSEL
= V
CPG1
= V
CPG2
= +2.4V, V
PLLIN+
= V
MOD+
= +1.3V, V
PLLIN-
= V
MOD-
= +1.1V, T
A
= +25°C,
unless otherwise noted. Typical values are at V
CC
= +5V, unless otherwise noted.)
PARAMETER
Charge-Pump Output Low
Measured at FB
Charge-Pump Output Current
Matching Positive to Negative
Charge-Pump Output Leakage
Charge-Pump Output Current
Drive (Note 1)
ANALOG CONTROL INPUTS
(GC1, GC2)
Input Current
Differential Output Voltage
Swing
Common-Mode Output Voltage
(Note 1)
Offset Voltage (Note 1)
I
GC_
V
GC_
= 1V to 4V
-50
50
µA
BASEBAND OUTPUTS
(IOUT+, IOUT-, QOUT+, QOUT-)
R
L
= 2kΩ differential
1
0.65
-50
0.85
50
Vp-p
V
mV
SYMBOL
CONDITIONS
V
CPG1
≤
0.5V, V
CPG2
≤
0.5V
V
CPG1
≤
0.5V, V
CPG2
≥
2.4V
V
CPG1
≥
2.4V, V
CPG2
≤
0.5V
V
CPG1
≥
2.4V, V
CPG2
≥
2.4V
Measured at FB
Measured at FB
Measured at CP
MIN
-0.12
-0.36
-0.72
-2.16
-5
-25
100
TYP
-0.1
-0.3
-0.6
-1.8
MAX
-0.08
-0.24
-0.48
-1.44
5
25
UNITS
MAX2106
mA
%
nA
µA
AC ELECTRICAL CHARACTERISTICS
(IC driven single-ended with RFIN- AC-terminated in 75Ω to GND, V
CC
= +4.75V to +5.25V, V
IOUT_
= V
QOUT_
= 0.59Vp-p,
C
IOUT_
= C
QOUT_
= 10pF, ƒ
LCLK
= 2MHz, R
IOUT_
= R
QOUT_
= 10kΩ, V
LOBUFSEL
= 0.5V, V
RFBAND
= V
INSEL
= V
CPG1
= V
CPG2
= +2.4V,
V
PLLIN+
= V
MOD+
= +1.3V, V
PLLIN-
= V
MOD-
= +1.1V, T
A
= +25°C, unless otherwise noted. Typical values are at V
CC
= +5V.)
PARAMETER
RF FRONT END
RFIN_ Input Frequency Range
RFIN_ Input Power for 0.59Vp-p
Baseband Levels
f
RFIN_
Inferred by quadrature gain and
phase-error test
V
GC1
= V
GC2
= +4V (min gain)
V
GC1
= V
GC2
= +1V (max gain)
f
LO
= 2175MHz
P
RFIN_
= -25dBm
f
LO
= 1550MHz
per tone
f
LO
= 950MHz
f
LO
= 2175MHz
P
RFIN_
= -65dBm
f
LO
= 1550MHz
per tone
f
LO
= 950MHz
Single
carrier
P
RFIN_
= -25dBm per tone,
f
LO
= 951MHz
P
RFIN_
= -40dBm,
signals within filter bandwidth
f
RFIN_
= 1550MHz,
V
GC1
= 1V, V
GC2
adjusted 0.59Vp-p
baseband level
P
RFIN_
= -65dBm
P
RFIN_
= -25dBm
925
-25
-68
10.5
11.5
10.5
-29
-26
-30
17
2
10.2
44.8
2175
MHz
dBm
dBm
dBm
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
RFIN_ Input Third-Order Intercept
Point (Note 3)
IP3
RFIN_
dBm
RFIN_ Input Second-Order Intercept
(Note 4)
Output-Referred 1dB Compression
Point (Note 5)
IP2
RFIN_
P1
dBOUT
dBm
dBV
dB
dB
3
Noise Figure
NF
_______________________________________________________________________________________
DBS Direct Downconverter
MAX2106
AC ELECTRICAL CHARACTERISTICS (continued)
(R
FIN
+ IC driven single-ended with RFIN- AC-terminated in 75Ω to GND, V
CC
= +4.75V to +5.25V, V
IOUT_
= V
QOUT_
= 0.59Vp-p,
C
IOUT_
= C
QOUT_
= 10pF, f
LCLK
= 2MHz, R
IOUT_
= R
QOUT_
= 10kΩ, V
LOBUFSEL
= 0.5V, V
RFBAND
= V
INSEL
= V
CPG1
= V
CPG2
= +2.4V,
V
PLLIN+
= V
MOD+
= +1.3V, V
PLLIN-
= V
MOD-
= +1.1V, T
A
= +25°C, unless otherwise noted. Typical values are at V
CC
= +5V.)
PARAMETER
R
FIN
+ Return Loss (Note 6)
LO 2nd Harmonic Rejection (Note 7)
LO Half Harmonic Rejection (Note 8)
LO Leakage Power (Notes 6, 9)
RFOUT PORT
(LOOPTHROUGH)
f = 925MHz
RFIN+ to RFOUT Gain (Note 10)
f = 1550MHz
f = 2175MHz
f = 925MHz
RFOUT Output Third-Order Intercept
Point (Note 10)
f = 1550MHz
f = 2175MHz
f = 925MHz
RFOUT Noise Figure (Note 10)
RFOUT Return Loss (Notes 6, 10)
BASEBAND CIRCUITS
Output Real Impedance (Note 1)
Baseband Highpass -3dB Frequency
(Note 1)
LPF -3dB Cutoff-Frequency Range
(Note 1)
Baseband Frequency Response
(Note 1)
LPF -3dB Cutoff-Frequency
Accuracy (Note 1)
Ratio of In-Filter-Band to Out-of-Filter-
Band Noise
Quadrature Gain Error
Quadrature Phase Error
IOUT_, QOUT_
C
IDC_
= C
QDC_
= 0.22µF
Controlled by FLCLK signal
Deviation from ideal 7th order,
Butterworth, up to 0.7
×
f
C
f
FLCLK
= 0.5MHz, f
C
= 8MHz
f
FLCLK
= 1.25MHz, f
C
= 19.3MHz
f
FLCLK
= 2.0625MHz, f
C
= 31.4MHz
f
IN_BAND
= 100Hz to 22.5MHz,
f
OUT_BAND
= 67.5MHz to 112.5MHz
Includes effects from baseband filters,
measured at 125kHz baseband
Includes effects from baseband filters,
measured at 125kHz baseband
8
-0.5
-5.5
-10
10
23
1.2
4
50
750
33
0.5
5.5
10
10
dB
dB
degrees
%
Ω
Hz
MHz
dB
f = 1550MHz
f = 2175MHz
925MHz < f < 2175MHz, Z
LOAD
= 75Ω
0.5
1.0
2.0
9
7
5
12.5
11
11
12
dB
dB
dBm
dB
SYMBOL
CONDITIONS
f
RFIN_
= 925MHz, Z
SOURCE
= 75Ω
f
RFIN_
= 2175MHz, Z
SOURCE
= 75Ω
Average level of V
IOUT_
, V
QOUT_
Average level of V
IOUT_
, V
QOUT_
Measured at R
FIN
+
MIN
TYP
+13
+14
32
41.5
-66
MAX
UNITS
dB
dB
dB
dBm
4
_______________________________________________________________________________________
DBS Direct Downconverter
AC ELECTRICAL CHARACTERISTICS (continued)
(IC driven single-ended with RFIN- AC-terminated in 75Ω to GND, V
CC
= +4.75V to +5.25V, V
IOUT_
= V
QOUT_
= 0.59Vp-p,
C
IOUT_
= C
QOUT_
= 10pF, ƒ
LCLK
= 2MHz, R
IOUT_
= R
QOUT_
= 10kΩ, V
LOBUFSEL
= 0.5V, V
RFBAND
= V
INSEL
= V
CPG1
= V
CPG2
= +2.4V,
V
PLLIN+
= V
MOD+
= +1.3V, V
PLLIN-
= V
MOD-
= +1.1V, T
A
= +25°C, unless otherwise noted. Typical values are at V
CC
= +5V.)
PARAMETER
SYNTHESIZER
SYNTHESIZER
XTLOUT Output Voltage Swing
Crystal Frequency Range (Note 1)
MOD+, MOD- Setup Time (Note 1)
MOD+, MOD- Hold Time (Note 1)
LOCAL OSCILLATOR
LOCAL OSCILLATOR
LO Tuning Range (Note 11)
LO Buffer Output Voltage (Note 1)
V
LOBUFSEL
≥
2.4V,
f
LO
= 925 MHz + 2175MHz
At 1kHz offset, f
LO
= 2175MHz
LO Phase Noise (Notes 6, 12)
At 10kHz offset, f
LO
= 2175MHz
At 100kHz offset, f
LO
= 2175MHz
RFIN+ to LO Input Isolation (Note 9)
Note 1:
Note 2
Note 3:
f
RFIN
= 2175MHz
590
70
-60
-75
-96
58
dB
dBc/Hz
1180
MHz
V
RMS
t
SUM
t
HM
Figure 1
Figure 1
Load = 10pF | | 10kΩ, f
XTLOUT
= 6MHz
0.75
4
7
0
1
1.5
7.26
Vp-p
MHz
ns
ns
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX2106
Minimum and maximum values are guaranteed by design and characterization over supply voltage.
Driving differential load of 10kΩ || 15pF.
Two signals are applied to RFIN_ at f
LO
- 100MHz and f
LO
- 199MHz. V
GC2
= 1V, V
GC1
is set so that the baseband out-
puts are at 590mVp-p. IM products are measured at baseband outputs but are referred to RF inputs.
Note 4:
Two signals are applied to RFIN_ at 1200MHz and 2150MHz. V
GC2
= 1V, V
GC1
is set so that the baseband outputs are at
590mVp-p. IM products are measured at baseband outputs but are referred to RF inputs.
Note 5:
P
RFIN_
= -40dBm so that front-end IM contributions are minimized.
Note 6:
Using L64733/L64734 demo board from LSI Logic.
Note 7:
Downconverted level, in dBc, of carrier present at f
LO
×
2, f
LO
= 1180MHz, f
VCO
= 590MHz, V
RFBAND
= unconnected (see
histogram plots).
Note 8:
Downconverted level, in dBc, of carrier present at f
O
/ 2, f
LO
= 2175MHz, f
VCO
= 1087.5MHz, V
RFBAND
= 2.4V.
Note 9:
Leakage is dominated by board parasitics.
Note 10:
V
CPG1
= V
CPG2
= V
RFBAND
= V
INSEL
= 0.5V, ƒ
LCLK
= 0.5MHz.
Note 11:
Guaranteed by design and characterization over supply and temperature.
Note 12:
Measured at tuned frequency with PLL locked. PLL loop bandwidth = 3kHz. All phase noise measurements assume tank
components have a Q > 50.
_______________________________________________________________________________________
5
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