MAX2369 MAXIM [Maxim Integrated Products], MAX2369 Datasheet - Page 7

• Manufacturer Part Number: MAX2369
• Description: Complete Dual-Band Quadrature Transmitter
• Manufacturer: MAXIM [Maxim Integrated Products]

13, 14, 15
10, 11
16, 17
18, 19
PIN
8, 9
12
20
21
1
2
3
4
5
6
7
CLK, DI, CS
IFIN+, IFIN-
TXGATE
IFOUT+,
_______________________________________________________________________________________
IFOUT-
NAME
LOCK
R
VGC
N.C.
RFH
V
V
V
V
V
RFL
BIAS
CC
CC
CC
CC
CC
Transmitter RF Output for Cellular Band (800MHz to 1000MHz)—for both FM and digital modes.
This open-collector output requires a pullup inductor to the supply voltage, which is part of the
output matching network and may be connected directly to the battery.
Transmitter RF Output for PCS Band (1700MHz to 2000MHz). This open collector output
requires a pullup inductor to the supply voltage. The pullup inductor is part of the output match-
ing network and may be connected directly to the battery.
Open-Collector Output Indicating Lock Status of the IF PLL. Requires a pullup resistor. Control
using configuration register bit LD_MODE.
Power Supply. Supply pin for the driver stage. V
close to the pin as possible. The ground vias for the bypass capacitor should not be shared by
any other branch. Bypass to ground with 100pF and 100nF capacitors.
Power Supply. Connect to pin 4 for normal operation.
Supply Pin for the Upconverter Stage. V
pin as possible. The ground vias for the bypass capacitor should not be shared by any other
branch.
Digital Input. A logic low on TXGATE shuts down everything except the IF PLL, IF VCO, and ser-
ial bus and registers. This mode is used for IF PLL settling before the transmit time slot.
Differential Inputs to the RF Upconverter. These pins are internally biased to +1.5V. The input
impedance for these ports is nominally 400Ω differential. The IF filter should be AC-coupled to
these ports. Keep the differential lines as short as possible to minimize stray pickup and shunt
capacitance.
No Connection. Leave these pins floating.
Bias Resistor Pin. RBIAS is internally biased to a bandgap voltage of +1.18V. An external resistor
or current source must be connected to this pin to set the bias current for the upconverters and PA
driver stages. The nominal resistor value is 16kΩ. This value can be altered to optimize the linearity
of the driver stage.
Input Pins from the 3-Wire Serial Bus (SPI/QSPI/MICROWIRE compatible).
An R-C filter on each of these pins may be used to reduce noise.
Power supply. Bypass to ground with a 1000pF capacitor.
Differential IF Outputs. These pins must be inductively pulled up to V
pass filter is connected between this port and IFIN+ and IFIN-. The pullup inductors can be part
of the filter structure. The differential output impedance of this port is nominally 600Ω. The trans-
mission lines from these pins should be short to minimize the pickup of spurious signals and
noise.
RF and IF Variable-Gain Control Analog Input. VGC floats to +1.5V. Apply
+0.5V to +2.6V to control the gain of the RF and IF stages. An RC filter on this pin may be used
to reduce DAC noise or PDM clock spurs from this line.
Supply Pin for the IF VGA. Bypass with a capacitor as close to the pin as possible. The bypass
capacitor must not share its ground vias with any other branches.
Quadrature Transmitter
CC
Complete Dual-Band
FUNCTION
must be bypassed to system ground as close to the
CC
must be bypassed to system ground as
CC
Pin Description
. A differential IF band-
7