MAX2668EYT+T Maxim Integrated Products, MAX2668EYT+T Datasheet - Page 7

• Manufacturer Part Number: MAX2668EYT+T
• Description: RF Amplifier Ultra thin HSPA/LTE ra thin HSPA/LTE LNA
• Manufacturer: Maxim Integrated Products
• Type: Tiny Low-Noise Amplifiersr

Specifications of MAX2668EYT+T

• Operating Frequency: 942 MHz
• P1db: 18 dBm
• Noise Figure: 16 dB
• Operating Supply Voltage: 2.7 V to 3.3 V
• Supply Current: 3.8 mA
• Maximum Power Dissipation: 167 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: LGA-6
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX2666/MAX2668 are low-power LNAs designed
for 3G mobile applications. The devices feature low
noise, high linearity, and three gain steps in a tiny plastic
package.
The devices require one matching inductor at the input
port in series with a DC-blocking capacitor to achieve
optimal performance in NF, gain, IIP3, and phase shift.
Table 1 presents the recommended input-matching
network values. The output port is internally matched to
50I, eliminating the need for external matching com-
ponents. At the output port, an external DC-blocking
capacitor should be used to isolate the control function
of the output pin.
A properly designed PCB is essential to any RF micro-
wave circuit. Use controlled-impedance lines on all
high-frequency inputs and outputs. Bypass V
decoupling capacitor located close to the device.
For long V
pling capacitors. Locate these additional capacitors
further away from the device package. Proper grounding
RFIN
CC
lines, it might be necessary to add decou-
0.01µF
(0201)
10%
C4
(0201)
OPEN
_______________________________________________________________________________________
C7
Tiny Low-Noise Amplifiers for HSPA/LTE
3.9nH Q 0.1nH (MAX2666)
12nH Q 0.2nH (MAX2668)
Input and Output Matching
DC Decoupling and Layout
Detailed Description
(0402)
L4
1
2
3
LNA_IN
BIAS_GND
LNA_GND
CC
MAX2666
MAX2668
with a
U1
LNA_OUT/GAIN0
V
Detailed Application Circuit in EV Kit
CC
0.01µF
(0402)
of the GND pins is essential. If the PCB uses a top-side
RF ground, connect it directly to the GND pins. For a
board where the ground is not on the component layer,
connect the GND pins to the board with multiple vias
close to the package.
The devices’ LNA_OUT/GAIN0 pin is also used as a
control pin for the LNA gain modes according to the gain
control table. GAIN0 logic level is set through an external
20kI resistor. An external DC-blocking capacitor should
be used to isolate the control function of this dual-pur-
pose pin (see the Typical Operating Circuit). The GAIN1
pin must be set to either logic-high or logic-low.
Refer to
Evaluation Kit schematic, Gerber data, PADS layout file,
and BOM information.
Table 1. Matching Component Values in
Different Bands
10%
GAIN1
C1
V
CC
1, 4, 10
BAND
6
5
4
5, 6
www.maxim-ic.com
8
(0201)
(0201)
0 I
0 I
R1
R2
C5
1000pF
10%
(0402)
SERIES C (nF)
GND
10
10
10
for the MAX2666/MAX2668
GAIN1
(0201)
20k I
0.01µF
(0201)
R4
10%
C3
SERIES L (nH)
Gain Control
RFOUT
GAIN0
3.9
12
12
7