MAX2370ETM+T Maxim Integrated Products, MAX2370ETM+T Datasheet - Page 7

• Manufacturer Part Number: MAX2370ETM+T
• Description: RF Transmitter IC TRANSMITTER QUAD-EP
• Manufacturer: Maxim Integrated Products

Specifications of MAX2370ETM+T

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

13, 14, 15
18, 19
23, 24
25, 26
30, 31
PIN
20
21
22
27
28
29
36
37
38
39
Complete 450MHz Quadrature Transmitter
IFOUT-, IFOUT+
TANK-, TANK+
CLK, DI, CS
V
Q+, Q-
NAME
SHDN
_______________________________________________________________________________________
CCIFCP
I+, I-
IFLO
IFCP
V
V
V
REF
V
GC
CC
CC
CC
CC
CMOS Inputs from the 3-Wire Serial Bus (SPI/QSPI/MICROWIRE Compatible). A small RC
lowpass filter on each of these pins can be used to reduce noise on these lines.
Differential IF Outputs. This port is active when IF_SEL is LOW and supports both FM and CDMA
modes. IFOUT+ and IFOUT- must be inductively pulled up to V
typically 560Ω. A 400Ω differential IF bandpass filter is connected between this port and IFIN+/-.
The pullup inductors can be part of the filter structure. The differential output impedance of this
port is nominally 400Ω, including the 560Ω external differential resistor. Keep the transmission
lines from these pins as short as possible to minimize the unintentional pickup of spurious signals
and noise.
RF and IF Gain-Control Analog Input. Accepts input voltages from 0.5V (minimum gain) to 2.5V
(maximum gain). When not driven, GC is internally biased to typically 1.5V. RC lowpass filter the
voltage applied to this pin to remove DAC noise or PDM clock spurs.
Power Supply for the IF VGA. Bypass to PC board ground with a 0.1µF capacitor placed as close
to the pin as possible. Do not share capacitor ground vias with other ground connections.
Power Supply for the I/Q Modulator. Bypass to PC board ground with a 0.1µF capacitor placed as
close to the pin as possible. Do not share capacitor ground vias with other ground connections.
Differential Q-Channel Baseband Inputs to the Modulator. Q+ and Q- connect directly to the
bases of a differential pair and require a typical 1.35V to (V
voltage.
Differential I-Channel Baseband Inputs to the Modulator. I+ and I- connect directly to the bases of
a differential pair and require a typical 1.35V to (V
Digital Input. Drive LOW to shut down the entire IC, drive high for normal operation. A small RC
lowpass filter can be used to filter digital noise.
Power Supply for the VCO Section. Bypass to PC board ground with a 0.1µF capacitor placed as
close to the pin as possible. Do not share capacitor ground vias with other ground connections.
IF LO O utp ut. P r ovi d es access to the IF V C O outp ut and can b e used to d r i ve an exter nal P LL. It can
b e d i sab l ed b y l og i c- l ow on the BU F_E N contr ol b i t. IFLO i s i nter nal l y b i ased to typ i cal l y 1.5V .
Differential Tank Connections for the IF VCO. TANK+ and TANK- are internally biased to
approximately 1.6V and must be AC-coupled to the external tank (can be DC-coupled if tank does
not sink or source current).
Reference Frequency Input. REF is internally biased to approximately 1.0V and must be AC-
coupled to the reference source. This is a high-impedance port and must be externally terminated
in the desired impedance.
Power Supply for the IF Charge Pump. This supply can be different from the system V
to PC board ground with a minimum 0.1µF capacitor placed as close to the pin as possible. Do
not share capacitor ground vias with other ground connections.
High-Impedance IF Charge-Pump Output. Connect to the tune input of the IF VCO through the IF
PLL loop filter. Keep the connection from IFCP to the tune input as short as possible to prevent
spurious pickup.
Power Supply for Digital Circuitry. Bypass to PC board ground with a minimum 0.1µF capacitor
placed as close to the pin as possible. Do not share capacitor ground vias with other ground
connections.
FUNCTION
Pin Description (continued)
CC
- 1.5V) external common-mode bias voltage.
CC
- 1.5V) external common-mode bias
CC
and differentially loaded with
CC
. Bypass
7