MAX9995ETX Maxim Integrated Products, MAX9995ETX Datasheet - Page 11

• Manufacturer Part Number: MAX9995ETX
• Description: Up-Down Converters Dual, SiGe, High-Lin earity, 1700MHz to 2
• Manufacturer: Maxim Integrated Products

Specifications of MAX9995ETX

• Maximum Input Frequency: 2200 MHz
• Maximum Power Dissipation: 2100 mW
• Maximum Operating Frequency: 350 MHz
• Maximum Power Gain: 6.2 dB
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Package / Case: TQFN-36 EP

Dual, SiGe, High-Linearity, 1700MHz to 2200MHz
internal LO SPDT switch that can be used for frequen-
cy-hopping applications. The switch selects one of the
two single-ended LO ports, allowing the external oscil-
lator to settle on a particular frequency before it is
switched in. LO switching time is typically less than
50ns, which is more than adequate for virtually all GSM
applications. If frequency hopping is not employed, set
the switch to either of the LO inputs. The switch is con-
trolled by a digital input (LOSEL): logic high selects
LO1, and logic low selects LO2. LO1 and LO2 inputs
are internally matched to 50Ω, requiring only a 22pF
DC-blocking capacitor.
A two-stage internal LO buffer allows a wide input
power range for the LO drive. All guaranteed specifica-
tions are for an LO signal power from -3dBm to +3dBm.
The on-chip low-loss balun, along with an LO buffer,
drives the double-balanced mixer. All interfacing and
matching components from the LO inputs to the IF out-
puts are integrated on-chip.
The core of the MAX9995 is a pair of double-balanced,
high-performance passive mixers. Exceptional linearity
is provided by the large LO swing from the on-chip LO
buffer. When combined with the integrated IF ampli-
fiers, the cascaded IIP3, 2RF-2LO rejection, and NF
performance is typically +25.6dBm, 66dBc, and 9.8dB,
respectively.
The MAX9995 mixers have an IF frequency range of
40MHz to 350MHz. The differential, open-collector IF
output ports require external pullup inductors to V
Note that these differential outputs are ideal for provid-
ing enhanced 2RF-2LO rejection performance. Single-
ended IF applications require a 4:1 balun to transform
the 200Ω differential output impedance to a 50Ω single-
ended output. After the balun, VSWR is typically 1.5:1.
The RF and LO inputs are internally matched to 50Ω.
No matching components are required. Return loss at
each RF port is typically 14dB over the entire input
range (1700MHz to 2200MHz), and return loss at the
LO ports is typically 18dB (1400MHz to 2000MHz). RF
and LO inputs require only DC-blocking capacitors for
interfacing.
Downconversion Mixer with LO Buffer/Switch
Differential IF Output Amplifiers
Applications Information
______________________________________________________________________________________
Input and Output Matching
High Linearity Mixers
CC
.
The IF output impedance is 200Ω (differential). For
evaluation, an external low-loss 4:1 (impedance ratio)
balun transforms this impedance down to a 50Ω single-
ended output (see the Typical Application Circuit).
Bias currents for the LO buffer and the IF amplifier are
optimized by fine tuning the resistors R1, R2, R4, and R5.
If reduced current is required at the expense of perfor-
mance, contact factory. If the ±1% bias resistor values
are not readily available, substitute standard ±5% values.
A properly designed PC board is an essential part of
any RF/microwave circuit. Keep RF signal lines as short
as possible to reduce losses, radiation, and induc-
tance. For the best performance, route the ground pin
traces directly to the exposed pad under the package.
The PC board exposed pad MUST be connected to the
ground plane of the PC board. It is suggested that mul-
tiple vias be used to connect this pad to the lower-level
ground planes. This method provides a good RF/ther-
mal-conduction path for the device. Solder the exposed
pad on the bottom of the device package to the PC
board. The MAX9995 Evaluation Kit can be used as a
reference for board layout. Gerber files are available
upon request at www.maxim-ic.com.
Proper voltage-supply bypassing is essential for high-
frequency circuit stability. Bypass each V
capacitor as close to the pin as possible (Typical
Application Circuit).
The exposed paddle (EP) of the MAX9995’s 36-pin thin
QFN-EP package provides a low thermal-resistance
path to the die. It is important that the PC board on
which the MAX9995 is mounted be designed to con-
duct heat from the EP. In addition, provide the EP with
a low-inductance path to electrical ground. The EP
MUST be soldered to a ground plane on the PC board,
either directly or through an array of plated via holes.
TRANSISTOR COUNT: 1414
PROCESS: SiGe BiCMOS
Exposed Pad RF/Thermal Considerations
Power-Supply Bypassing
Layout Considerations
Chip Information
Bias Resistors
CC
pin with a
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