MAX9504B Maxim, MAX9504B Datasheet - Page 9

• Manufacturer Part Number: MAX9504B
• Description: The MAX9504A/MAX9504B 3V/5V, ground-sensing amplifiers with a fixed gain of 6dB provide high output current while consuming only 10nA of current in shutdown mode
• Manufacturer: Maxim

Table 1. 2nd-Order Butterworth Lowpass
Filter Normalized Values
Table 1 shows the normalized 2nd-order Butterworth
LPF component values at 1 rad/s with a source/load
impedance of 1Ω.
With the following equations, the L and C can be calcu-
lated for the cutoff frequency (f
shows the appropriate L and C values for different
source/load impedances, the bench measurement val-
ues for the -3dB frequency and the attenuation at
27MHz. There is approximately 20dB attenuation at
27MHz, which decreases the spikes at the sampling
frequency.
Figure 4 shows the frequency response for R1 = R2 =
150Ω. At 6MHz, the attenuation is about 1.4dB. The
attenuation at 27MHz is about 20dB. Figure 5 shows
the multiburst response for R1 = R2 = 150Ω.
Figure 3. 3rd-Order Butterworth LPF with MAX9504
2nd-Order Butterworth Lowpass Filter Realization
Rn1 = Rn2 (Ω)
CURRENT
1
VIDEO
DAC
_______________________________________________________________________________________
C
L
150Ω
1
1
R1
=
=
Cn1 (F)
1.414
2
Ln R
2
π
120pF
Cn
π
1 1
fcR
fc
C1
3-POLE RECONSTRUCTION LPF
1
1
C
) at 9MHz. Table 2
3V/5V, 6dB Video Amplifiers with
4.7µH
6.8pF
L1
C3
High Output-Current Capability
Ln1 (H)
1.414
C2
120pF
R2
150Ω
Table 2. Bench Measurement Values
(2nd-Order LPF)
Figure 4. Frequency Response for 2nd-Order Lowpass Filter
R1 = R2
V
CC
150
200
300
(Ω)
75
-10
-20
-30
-40
-50
-60
(pF)
330
150
120
C1
82
0
SHDN
IN
0.1
MAX9504
(µH)
GND
1.8
3.9
4.7
8.2
V
L1
CC
FREQUENCY RESPONSE
FREQUENCY (MHz)
1
OUT
FREQUENCY
FB
(MHz)
3dB
8.7
9.0
9.3
8.7
10
C7
0.1µF
75Ω
R3
ATTENUATION AT
27MHz (dB)
100
V
V
CC
20
20
22
20
OUT
9