LTC5593IUH#TRPBF Linear Technology, LTC5593IUH#TRPBF Datasheet - Page 23

• Manufacturer Part Number: LTC5593IUH#TRPBF
• Manufacturer: Linear Technology

Specifications of LTC5593IUH#TRPBF

• Operating Supply Voltage: 3.3V
• Operating Temperature (min): -40C
• Operating Temperature Classification: Industrial
• Lead Free Status / Rohs Status: Compliant

For optimum single-ended performance, the differential
IF output must be combined through an external IF
transformer or a discrete IF balun circuit. The evaluation
board (see Figures 1 and 2) uses a 4:1 IF transformer for
impedance transformation and differential to single-ended
conversion. It is also possible to eliminate the IF transformer
and drive differential filters or amplifiers directly.
At IF frequencies, the IF output impedance can be modeled
as 260Ω in parallel with 2.3pF . The equivalent small-signal
model, including bondwire inductance, is shown in Figure 9.
Frequency-dependent differential IF output impedance is
listed in Table 3. This data is referenced to the package
pins (with no external components) and includes the ef-
fects of IC and package parasitics.
Bandpass IF Matching
The bandpass IF matching configuration, shown in
Figures 1 and 7, is best suited for IF frequencies in the
90MHz to 600MHz range. Resistor R2A may be used to
APPLICATIONS INFORMATION
L3A (OR SHORT)
Figure 8. IF Amplifier Schematic with Bandpass Match
100mA
23
LTC5593
22
IFA
V
CCIFA
+
L1A
AMP
R2A
T1A
IF
reduce the IF output resistance for greater bandwidth and
inductors L1A and L2A resonate with the internal IF output
capacitance at the desired IF frequency. The value of L1A,
L2A can be estimated as follows:
where C
C5A
C7A
L2A
4:1
L1A = L2A =
21
4mA
IFA
IF
–
is the internal IF capacitance (listed in Table 3).
BIAS
Figure 9. IF Output Small-Signal Model
IFA
20
DC POWER)
(OPTION TO
LTC5593
V
REDUCE
IFBA
CCA
R1A


5593 F08
(
2πf
22
IF
0.9nH
IFA
)
2
1
+
• 2 • C
R IF
C IF
IF
21


IF A
0.9nH
–
LTC5593
5593 F09
23
5593p