MAX2830ETM+T Maxim Integrated Products, MAX2830ETM+T Datasheet - Page 21

• Manufacturer Part Number: MAX2830ETM+T
• Description: RF Transceiver 2.4GHz to 2.5GHz 802 .11g-b RF Transceive
• Manufacturer: Maxim Integrated Products

Specifications of MAX2830ETM+T

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

an antenna diversity path between the ANT2 port (pins
9 and 10) and the receiver. When RXTX = 1, the PA
and transmit path are automatically connected to the
ANT2 port, regardless of the logic state of ANTSEL. For
solutions not requiring antenna diversity, set ANTSEL
logic-level high, enabling only the ANT2 port for both
receive and transmit modes.
The ANT1 and ANT2 differential ports are internally AC-
coupled and internally matched to 100Ω. Directly con-
nect 2:1 baluns or balanced bandpass filters (BPFs) to
these ports for applications requiring antenna diversity.
For applications not requiring antenna diversity, only a
single balun or balanced BPF is required on the ANT2
port, and the ANT1 port can be left open. Provide elec-
trically symmetrical input traces to the baluns to main-
tain IP2 and RF common-mode noise rejection for the
receiver, and to maintain a balanced load for the PA.
After the switch, the receiver integrates an LNA and VGA
with a 95dB digitally programmable gain control range,
direct-conversion downconverters, I/Q baseband low-
pass filters with programmable LPF corner frequencies,
analog RSSI and integrated DC-offset correction circuitry.
A logic-low on the RXTX input (pin 48) and a logic-high on
the SHDN input (pin 12) enable the receiver.
The LNA has three gain modes: max gain, max gain
-16dB, and max gain -33dB. The three LNA gain
modes can be serially programmed through the SPI™
Table 2. LNA Gain-Control Settings (Pins
B7:B6 or Register A3:A0 = 1011, D6:D5)
Table 3. Receiver Baseband VGA Gain-
Step Value (Pins B5:B1 or Register D4:D0,
A3:A0 = 1011)
SPI is a trademark of Motorola, Inc.
2.4GHz to 2.5GHz 802.11g/b RF Transceiver, PA,
B7 OR D6
1
1
0
PIN/BIT
B1/D0
B2/D1
B3/D2
B4/D3
B5/D4
B6 OR D5
X
1
0
______________________________________________________________________________________
Medium
NAME
High
Low
and Rx/Tx/Antenna Diversity Switch
GAIN STEP (dB)
Max gain - 16dB (typ)
Max gain - 33dB (typ)
LNA Gain Control
DESCRIPTION
Max gain
16
32
2
4
8
Receiver
interface by programming bits D6:D5 in Register 11
(A3:A0 = 1011) or programmed in parallel through the
digital logic gain-control pins, B7 (pin 6) and B6 (pin 3).
Set bit D12 = 1 in Register 8 (A3:A0 = 1000) to enable
programming through the SPI interface, or set bit D12 =
0 to enable parallel programming. See Table 2 for LNA
gain-control settings.
The receiver baseband variable-gain amplifiers provide
62dB of gain control range programmable in 2dB steps.
The VGA gain can be serially programmed through the
SPI interface by setting bits D4:D0 in Register 11 (A3:A0
= 1011) or programmed in parallel through the digital
logic gain-control pins, B5 (pin 14), B4 (pin 34), B3 (pin
8), B2 (pin 11), and B1 (pin 23). Set bit D12 = 1 in
Register 8 (A3:A0 = 1000) to enable serial programming
through the serial interface or set bit D12 = 0 to enable
parallel programming through the external logic pins.
See Table 3 for the gain-step value and Table 4 for
baseband VGA gain-control settings.
The receiver integrates lowpass filters that provide an
upper -3dB corner frequency of 8.5MHz (nominal mode)
with 50dB of attenuation at 20MHz, and 45ns of group
delay ripple in the passband (10kHz to 8.5MHz). The
upper -3dB corner frequency is tightly controlled on-chip
and does not require user adjustment. However, provi-
sions are made to allow fine tuning of the upper -3dB
Table 4. Baseband VGA Gain-Control
Settings in Receiver Gain-Control Register
(Pin B5:B1 or Register D4:D0, A3:A0 = 1011)
Table 5. Receiver LPF Coarse -3dB
Corner Frequency Settings in Register
(A3:A0 = 1000)
BITS (D1:D0)
B5:B1 OR D4:D0
00
01
10
11
11111
11110
11101
00000
:
Receiver Baseband Lowpass Filter
FREQUENCY (MHz)
Baseband Variable-Gain Amplifier
-3dB CORNER
7.5
8.5
15
18
Max - 2dB
Max - 4dB
GAIN
Max
Min
:
Turbo 1
Turbo 2
MODE
11b
11g
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