MAX2830ETM+T Maxim Integrated Products, MAX2830ETM+T Datasheet - Page 23

• 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

The transmitter integrates baseband lowpass filters,
direct-upconversion mixers, a VGA, a PA driver, and a lin-
ear RF PA with a power detector. A logic-high on the
RXTX input (pin 48) and a logic-high on the SHDN input
(pin 12) enable the transmitter. The PA outputs are routed
to ANT2, regardless of the state at ANTSEL.
The differential analog inputs of the transmitter baseband
amplifier I/Q inputs (TXBBI+, TXBBI-, TXBBQ+, TXBBQ-)
have a differential impedance of 20kΩ || 1pF. The inputs
require an input common-mode voltage of 0.9V to 1.3V,
which is provided by the DC-coupled I and Q DAC out-
puts of the accompanying baseband IC.
The transmitter integrates lowpass filters that can be
tuned to -3dB corner frequencies of 8MHz (11b),
11MHz (11g), 16.5MHz (turbo 1 mode), and 22.5MHz
(turbo 2 mode) through programming bits D1:D0 in
Table 9. Transmitter LPF Coarse -3dB
Corner Frequency Settings in Register
(A3:A0 = 1000)
Table 10. Transmitter LPF Fine -3dB
Corner Frequency Adjustment in
Register (A3:A0 = 0111)
2.4GHz to 2.5GHz 802.11g/b RF Transceiver, PA,
BITS (D1:D0)
BITS (D5:D3)
00
01
10
11
101–111
000
001
010
011
100
101
Transmitter Baseband Lowpass Filtering
______________________________________________________________________________________
FREQUENCY (MHz)
Transmitter I/Q Baseband Inputs
-3dB CORNER
% ADJUSTMENT RELATIVE TO
16.5
22.5
11
8
and Rx/Tx/Antenna Diversity Switch
COARSE SETTING
110 (11g)
Not used
100
105
115
90
95
Transmitter
Turbo 1
Turbo 2
MODE
11b
11g
Register 8 (A3:A0 = 1000) and bit D5:D3 in Register 7
(A3:A0 = 0111). The -3dB corner frequency is tightly
controlled on-chip and does not require user adjust-
ment. Additionally, provisions are made to fine tune the
-3dB corner frequency through bits D5:D3 in the Filter
Programming register (A3:A0 = 0111). See Tables 9
and 10.
The variable-gain amplifier of the transmitter provides
31dB of gain control range programmable in 0.5dB
steps over the top 8dB of the gain control range and in
1dB steps below that. The transmitter gain can be pro-
grammed serially through the SPI interface by setting
bits D5:D0 in Register 12 (A3:A0 = 1100) or in parallel
through the digital logic gain-control pins B6:B1 (pins
3, 6, 8, 11, 14, 23, and 34, respectively). Set bit D10 =
0 in Register 9 (A3:A0 = 1001) to enable parallel pro-
gramming, and set bit D10 = 1 to enable programming
through the 3-wire serial interface. See Table 11 for the
transmitter VGA gain-control settings.
Table 11. Transmitter VGA Gain-Control
Settings
NO.
63
62
61
49
48
47
46
45
44
5
4
3
2
1
0
:
:
D5:D0 OR
Transmitter Variable-Gain Amplifier
111111
111110
111101
110001
110000
101111
101110
101101
101100
000101
000100
000011
000010
000001
000000
B6:B1
:
:
OUTPUT SIGNAL POWER
Max - 0.5dB
Max - 1.0dB
Max - 7.5dB
Max - 29dB
Max - 29dB
Max - 30dB
Max - 30dB
Max - 31dB
Max - 31dB
Max - 7dB
Max - 8dB
Max - 8dB
Max - 9dB
Max - 9dB
Max
:
:
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