参数资料
型号: AD8532
厂商: Analog Devices, Inc.
英文描述: Low Cost, 250 mA Output Single-Supply Amplifiers(低成本,250mA输出,单电源双放大器)
中文描述: 低成本,250 mA输出单电源放大器(低成本,250mA的输出,单电源双放大器)
文件页数: 12/16页
文件大小: 220K
代理商: AD8532
AD8531/AD8532/AD8534
REV. A
–12–
A Single-Supply Headphone Amplifier
Because of its speed and large output drive, the AD8531/AD8532/
AD8534 makes an excellent headphone driver, as illustrated in
Figure 40. Its low supply operation and rail-to-rail inputs and
outputs give a maximum signal swing on a single +5 V supply.
T o ensure maximum signal swing available to drive the head-
phone, the amplifier inputs are biased to V+/2, which in this
case is 2.5 V. T he 100 k
resistor to the positive supply is
equally split into two 50 k
resistors, with their common point
bypassed by 10
μ
F to prevent power supply noise from contami-
nating the audio signal.
T he audio signal is then ac-coupled to each input through a
10
μ
F capacitor. A large value is needed to ensure that the
20 Hz audio information is not blocked. If the input already has
the proper dc bias, the ac coupling and biasing resistors are not
required. A 270
μ
F capacitor is used at the output to couple the
amplifier to the headphone. T his value is much larger than that
used for the input because of the low impedance of the head-
phones, which can range from 32
to 600
. An additional
16
resistor is used in series with the output capacitor to pro-
tect the op amp’s output stage by limiting capacitor discharge
current. When driving a 48
load, the circuit exhibits less than
0.3% T HD+N at output drive levels of 4 V p-p.
1/2
AD8532
16
50k
270μF
LEFT
HEADPHONE
10μF
50k
50k
100k
10μF
LEFT
INPUT
+V + 5V
1/2
AD8532
16
50k
270μF
RIGHT
HEADPHONE
10μF
50k
50k
100k
10μF
RIGHT
INPUT
+V
+V + 5V
1μF/0.1μF
Figure 40. A Single-Supply, Stereo Headphone Driver
A Single-Supply, T wo-Way Loudspeaker Crossover Network
Active filters are useful in loudspeaker crossover networks for
reasons of small size, relative freedom from parasitic effects, the
ease of controlling low/high channel drive and the controlled driver
damping provided by a dedicated amplifier. Both Sallen-K ey
(SK ) and multiple-feedback (MFB) filter architectures are use-
ful in implementing active crossover networks. T he circuit
shown in Figure 41 is a single-supply, two-way active crossover
which combines the advantages of both filter topologies. T his
active crossover exhibits less than 0.4% T HD+N at output lev-
els of 1.4 V rms using general purpose unity-gain HP/L P stages.
In this two-way example, the L O signal is a dc-500 Hz L P
woofer output, and the HI signal is the HP (>500 Hz)
tweeter output. U1B forms an L P section at 500 Hz, while
U1A provides a HP section, covering frequencies
500 Hz.
V
IN
3
2
1
U1A
AD8532
+V
S
4
R1
31.6k
C1
0.01μF
C2
0.01μF
R2
31.6k
R5
31.6k
R6
31.6k
R4
49.9
HI
LO
500Hz
AND UP
DC –
500Hz
6
5
7
C3
0.01μF
U1B
AD8532
C4
0.02μF
R7
15.8k
R3
49.9
+
+
100k
+V
S
10μF
100k
100k
C
IN
10μF
R
IN
100k
0.1μF
100μF/25V
+V
S
TO U1
+5V
COM
100k
Figure 41. A Single-Supply, Two-Way Active Crossover
T he crossover example frequency of 500 Hz can be shifted
lower or higher by frequency scaling of either resistors or ca-
pacitors. In configuring the circuit for other frequencies,
complementary L P/HP action must be maintained between
sections, and component values within the sections must be in
the same ratio. T able II provides a design aid to adaptation,
with suggested standard component values for other frequencies.
T able II. RC Component Selection for Various
Crossover Frequencies
Crossover
Frequency (Hz)
100
200
319
500
1 k
2 k
5 k
10 k
R1/C1 (U1A)
1
R5/C3 (U1B)
2
160 k
/0.01
μ
F
80.6 k
/0.01
μ
F
49.9 k
/0.01
μ
F
31.6 k
/0.01
μ
F
16 k
/0.01
μ
F
8.06 k
/0.01
μ
F
3.16 k
/0.01
μ
F
1.6 k
/0.01
μ
F
NOT ES
Applicable for filter
α
= 2.
1
For Sallen-K ey stage U1A: R1 = R2, and C1 = C2, etc.
2
For Multiple Feedback stage U1B: R6 = R5, R7 = R5/2, and
C4 = 2C3.
For additional information on the active filters and active cross-
over networks, please consult the data sheet for the OP279, a
dual rail-to-rail high-output current operational amplifier.
相关PDF资料
PDF描述
AD8534 Low Cost, 250 mA Output Single-Supply Amplifiers(低成本,250mA输出,单电源四放大器)
AD8538_07 Low Power, Precision, Auto-Zero Op Amps
AD8539 Low Power, Precision, Auto-Zero Op Amps
AD8541AKS-R2 General Purpose CMOS Rail-to-Rail Amplifiers
AD8541AKS-REEL7 General Purpose CMOS Rail-to-Rail Amplifiers
相关代理商/技术参数
参数描述
AD8532AN 制造商:Analog Devices 功能描述:OP AMP DUAL HIGH O/P RRI/O 8532
AD8532AR 功能描述:IC OPAMP GP R-R CMOS 3MHZ 8SOIC RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:160 系列:- 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:10 V/µs 增益带宽积:9MHz -3db带宽:- 电流 - 输入偏压:1pA 电压 - 输入偏移:250µV 电流 - 电源:730µA 电流 - 输出 / 通道:28mA 电压 - 电源,单路/双路(±):2.7 V ~ 5.5 V,±1.35 V ~ 2.75 V 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:16-SOIC(0.154",3.90mm 宽) 供应商设备封装:16-SOIC N 包装:管件
AD8532ARM 制造商:Analog Devices 功能描述:
AD8532ARM-R2 制造商:Analog Devices 功能描述:OP Amp Dual GP R-R I/O 6V 8-Pin MSOP T/R
AD8532ARM-REEL 制造商:Analog Devices 功能描述:OP Amp Dual GP R-R I/O 6V 8-Pin MSOP T/R 制造商:Rochester Electronics LLC 功能描述:CMOS RAIL/RAIL INPUT/OUTPUT OP AMP - Tape and Reel