參數(shù)資料
型號: MAX7426CUA+T
廠商: Maxim Integrated Products
文件頁數(shù): 11/12頁
文件大小: 0K
描述: IC FILTER LOWPASS 5TH 8UMAX
產(chǎn)品培訓(xùn)模塊: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
標(biāo)準(zhǔn)包裝: 2,500
濾波器類型: 橢圓,低通開關(guān)電容器
頻率 - 截止或中心: 12kHz
濾波器數(shù): 1
濾波器階數(shù): 5th
電源電壓: 4.5 V ~ 5.5 V
安裝類型: 表面貼裝
封裝/外殼: 8-TSSOP,8-MSOP(0.118",3.00mm 寬)
供應(yīng)商設(shè)備封裝: 8-uMAX
包裝: 帶卷 (TR)
MAX7426/MAX7427
5th-Order, Lowpass, Elliptic,
Switched-Capacitor Filters
8
_______________________________________________________________________________________
Detailed Description
The MAX7426/MAX7427 family of 5th-order, elliptic,
lowpass filters provides sharp rolloff with good stop-
band rejection. All parts operate with a 100:1 clock-to-
corner frequency ratio.
Most SCFs are designed with biquadratic sections.
Each section implements two pole-zero pairs, and the
sections can be cascaded to produce higher-order fil-
ters. The advantage to this approach is ease of design.
However, this type of design is highly sensitive to com-
ponent variations if any section’s Q is high. The
MAX7426/MAX7427 use an alternative approach, which
is to emulate a passive network using switched-capaci-
tor integrators with summing and scaling. The passive
network may be synthesized using CAD programs or
may be found in many filter books. Figure 1 shows a
basic 5th-order ladder elliptic filter structure.
A switched-capacitor filter that emulates a passive lad-
der filter retains many of the same advantages. The
component sensitivity of a passive ladder filter is low
when compared to a cascaded biquadratic design,
because each component affects the entire filter shape
rather than a single pole-zero pair. In other words, a
mismatched component in a biquadratic design has a
concentrated error on its respective poles, while the
same mismatch in a ladder filter design spreads its
error over all poles.
Elliptic Characteristics
Lowpass elliptic filters such as the MAX7426/MAX7427
provide the steepest possible rolloff with frequency of
the four most common filter types (Butterworth, Bessel,
Chebyshev, and elliptic). The high Q value of the poles
near the passband edge combined with the stopband
zeros allow for the sharp attenuation characteristic of
elliptic filters, making these devices ideal for anti-alias-
ing and post-DAC filtering in single-supply systems
(see the Anti-Aliasing and Post-DAC Filtering section).
In the frequency domain (Figure 2), the first transmis-
sion zero causes the filter’s amplitude to drop to a mini-
mum level. Beyond this zero, the response rises as the
frequency increases until the next transmission zero.
The stopband begins at the stopband frequency, fS. At
frequencies above fS, the filter’s gain does not exceed
the gain at fS. The corner frequency, fC, is defined as
the point where the filter output attenuation falls just
below the passband ripple. The transition ratio (r) is
defined as the ratio of the stopband frequency to the
corner frequency:
r = fS / fC
The MAX7426/MAX7427 have a transition ratio of 1.25
and typically 37dB of stopband rejection.
Clock Signal
External Clock
These SCFs are designed for use with external clocks
that have a 40% to 60% duty cycle. When using an
external clock, drive the CLK pin with a CMOS gate
C4
C2
L4
C5
C3
C1
VIN
+
-
RL
L2
RS
Figure 1. 5th-Order Ladder Elliptic Filter Network
NAME
FUNCTION
1
COM
Common Input Pin. Biased internally at midsupply. Bypass externally to GND with a 0.1F capacitor. To
override internal biasing, drive with an external supply.
2
IN
Filter Input
PIN
3
GND
Ground
4
VDD
Positive Supply Input, +5V for MAX7426 or +3V for MAX7427
8
CLK
Clock Input. Connect an external capacitor (COSC) from CLK to GND to set the internal oscillator
frequency. To override the internal oscillator, connect to an external clock.
7
SHDN
Shutdown Input. Drive low to enable shutdown mode; drive high or connect to VDD for normal operation.
6
OS
Offset Adjust Input. To adjust output offset, bias OS with a resistive voltage-divider between an external
supply and ground. Connect OS to COM if no offset adjustment is needed.
5
OUT
Filter Output
Pin Description
相關(guān)PDF資料
PDF描述
MC9S08SH8MSC IC MCU 8BIT 8K FLASH 8-SOIC
HSP43220JC-25Z IC DECIMATING DGTL FILTER 84PLCC
HSP43216VC-52Z IC HALFBAND FILTER 100-MQFP
MC9S08RE8FJE IC MCU 8K FLASH 8MHZ 32-LQFP
LTC1061ACN IC FILTER BUILDNG BLK TRPL 20DIP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX7426EPA 功能描述:有源濾波器 RoHS:否 制造商:Maxim Integrated 通道數(shù)量:1 截止頻率:150 KHz 電源電壓-最大:11 V 電源電壓-最小:4.74 V 最大工作溫度:+ 85 C 安裝風(fēng)格:Through Hole 封裝 / 箱體:PDIP N 封裝:Tube
MAX7426EPA+ 功能描述:有源濾波器 5th-Order Lowpass Elliptic Filter RoHS:否 制造商:Maxim Integrated 通道數(shù)量:1 截止頻率:150 KHz 電源電壓-最大:11 V 電源電壓-最小:4.74 V 最大工作溫度:+ 85 C 安裝風(fēng)格:Through Hole 封裝 / 箱體:PDIP N 封裝:Tube
MAX7426EUA 功能描述:有源濾波器 RoHS:否 制造商:Maxim Integrated 通道數(shù)量:1 截止頻率:150 KHz 電源電壓-最大:11 V 電源電壓-最小:4.74 V 最大工作溫度:+ 85 C 安裝風(fēng)格:Through Hole 封裝 / 箱體:PDIP N 封裝:Tube
MAX7426EUA+ 功能描述:有源濾波器 5th-Order Lowpass Elliptic Filter RoHS:否 制造商:Maxim Integrated 通道數(shù)量:1 截止頻率:150 KHz 電源電壓-最大:11 V 電源電壓-最小:4.74 V 最大工作溫度:+ 85 C 安裝風(fēng)格:Through Hole 封裝 / 箱體:PDIP N 封裝:Tube
MAX7426EUA+T 功能描述:有源濾波器 5th-Order Lowpass Elliptic Filter RoHS:否 制造商:Maxim Integrated 通道數(shù)量:1 截止頻率:150 KHz 電源電壓-最大:11 V 電源電壓-最小:4.74 V 最大工作溫度:+ 85 C 安裝風(fēng)格:Through Hole 封裝 / 箱體:PDIP N 封裝:Tube