LT6604CUFF-10#PBF Linear Technology, LT6604CUFF-10#PBF Datasheet - Page 11

• Manufacturer Part Number: LT6604CUFF-10#PBF
• Description: IC AMP DIFF LN DUAL 34-QFN
• Manufacturer: Linear Technology

Specifications of LT6604CUFF-10#PBF

• Amplifier Type: Differential
• Number Of Circuits: 2
• Output Type: Differential
• Current - Input Bias: 40µA
• Voltage - Input Offset: 8000µV
• Current - Supply: 36mA
• Voltage - Supply, Single/dual (±): 3 V ~ 11 V, ±1.5 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 34-QFN
• No. Of Amplifiers: 2
• Input Offset Voltage: 35mV
• Bandwidth: 10MHz
• Supply Voltage Range: 3V To 11V
• Supply Current: 36mA
• Amplifier Case Style: QFN
• No. Of Pins: 34
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output / Channel: -
• -3db Bandwidth: -
• Slew Rate: -
• Gain Bandwidth Product: -

APPLICATIONS INFORMATION
Figure 5 is a laboratory setup that can be used to char-
acterize the LT6604-10 using single-ended instruments
with 50Ω source impedance and 50Ω input impedance.
For a unity gain confi guration the LT6604-10 requires an
402Ω source resistance yet the network analyzer output is
calibrated for a 50Ω load resistance. The 1:1 transformer,
53.6Ω and 388Ω resistors satisfy the two constraints
above. The transformer converts the single-ended source
into a differential stimulus. Similarly, the output of the
LT6604-10 will have lower distortion with larger load
resistance yet the analyzer input is typically 50Ω. The 4:1
turns (16:1 impedance) transformer and the two 402Ω
resistors of Figure 5, present the output of the LT6604-10
with a 1600Ω differential load, or the equivalent of 800Ω
to ground at each output. The impedance seen by the
network analyzer input is still 50Ω, reducing refl ections in
the cabling between the transformer and analyzer input.
Differential and Common Mode Voltage Ranges
The differential amplifi ers inside the LT6604-10 contain
circuitry to limit the maximum peak-to-peak differential
voltage through the fi lter. This limiting function prevents
excessive power dissipation in the internal circuitry and
provides output short-circuit protection. The limiting
function begins to take effect at output signal levels
above 2V
This is illustrated in Figure 6; the LT6604-10 channel was
confi gured with unity passband gain and the input of the
fi lter was driven with a 1MHz signal. Because this voltage
limiting takes place well before the output stage of the
NETWORK
ANALYZER
SOURCE
50Ω
P-P
53.6Ω
and it becomes noticeable above 3.5V
COILCRAFT
TTWB-1010
1:1
388Ω
388Ω
34
4
6
2
Figure 5
1/2
LT6604-10
+
–
25
–2.5V
7
2.5V
+
–
0.1μF
0.1μF
27
29
402Ω
402Ω
COILCRAFT
TTWB-16A
4:1
NETWORK
ANALYZER
INPUT
660410 F05
50Ω
P-P
.
fi lter reaches the supply rails, the input/output behavior
of the IC shown in Figure 6 is relatively independent of
the power supply voltage.
The two amplifi ers inside the LT6604-10 channel have
independent control of their output common mode voltage
(see the Block Diagram section). The following guidelines
will optimize the performance of the fi lter.
V
AC ground with a 0.01μF capacitor or some instability may
be observed. V
source, provided it remains at least 1.5V above V
least 1.5V below V
voltage of V
matched, their absolute value can vary by ±20%. This
should be taken into consideration when connecting an
external resistor network to alter the voltage of V
V
common mode output voltage is required, connect V
to a voltage source or resistor network. For 3V and 3.3V
supplies the voltage at V
to the mid supply level. For example, voltage (V
1.65V on a single 3.3V supply. For power supply voltages
higher than 3.3V the voltage at V
supply. The voltage on V
below the voltage on V
not be more than 2V above the voltage on V
a high impedance input.
MID
OCM
can be allowed to fl oat, but it must be bypassed to an
can be shorted to V
–100
–120
MID
–20
–40
–60
–80
20
0
0
MID
. While the internal 11k resistors are well
COMPRESSION POINTS
1dB PASSBAND GAIN
2ND HARMONIC
3RD HARMONIC
+
can be driven from a low impedance
. An internal resistor divider sets the
1
1MHz INPUT LEVEL (V
3RD HARMONIC
MID
OCM
85°C
2
OCM
25°C
MID
Figure 6
. The voltage on V
should not be more than 1V
must be less than or equal
85°C
3
for simplicity. If a different
OCM
1MHz 85°C
2ND HARMONIC
25°C
4
P-P
can be set above mid
LT6604-10
1MHz 25°C
)
5
660410 F06
MID
6
OCM
. V
–
MID
11
OCM
should
OCM
and at
660410fb
.
OCM
) ≤
is