AD8532AR ,Low Cost, 250 mA Output Single-Supply AmplifiersSpecifications subject to change without notice.–2– REV. BAD8531/AD8532/AD8534(@ V = +5.0 V, V = 2. ..
AD8532ARM ,Low Cost, 250 mA Output Single-Supply AmplifiersAPPLICATIONS8-Lead Epoxy DIPMultimedia Audio8-Lead SO(N Suffix)LCD Driver(R Suffix)ASIC Input or Ou ..
AD8532ARM-REEL ,Low Cost, 250 mA Output Dual-Supply AmplifiersCHARACTERISTICSOutput Voltage High V I = 10 mA 2.85 2.92 VOH L–40∞C £ T £ +85∞C 2.8 VAOutput Voltag ..
AD8532AR-REEL ,Low Cost, 250 mA Output Dual-Supply AmplifiersGENERAL DESCRIPTION+IN A 3 6 OUT AThe AD8531, AD8532, and AD8534 are single, dual and quadV– 4 5 NU ..
AD8532AR-REEL7 ,Low Cost, 250 mA Output Dual-Supply AmplifiersCHARACTERISTICSOffset Voltage V 25 mVOS–40∞C £ T £ +85∞C30mVAInput Bias Current I 550 pAB–40∞C £ T ..
AD8532ARU ,Low Cost, 250 mA Output Single-Supply AmplifiersCHARACTERISTICSOutput Voltage High V I = 10 mA 2.85 2.92 VOH L–40
AD8531AR-AD8531ART-AD8532AN-AD8532AR-AD8532ARM-AD8532ARU-AD8534AR-AD8534ARU
Low Cost, 250 mA Output Single-Supply Amplifiers
REV.B
Low Cost, 250 mA Output
Single-Supply Amplifiers
GENERAL DESCRIPTIONThe AD8531, AD8532 and AD8534 are single, dual and quad
rail-to-rail input and output single-supply amplifiers featuring
250 mA output drive current. This high output current makes
these amplifiers excellent for driving either resistive or capacitive
loads. AC performance is very good with 3 MHz bandwidth,
5 V/ms slew rate and low distortion. All are guaranteed to oper-
ate from a +3 volt single supply as well as a +5 volt supply.
The very low input bias currents enable the AD853x to be used
for integrators and diode amplification and other applications
requiring low input bias current. Supply current is only 750 mA
per amplifier at 5 volts, allowing low current applications to
control high current loads.
Applications include audio amplification for computers, sound
ports, sound cards and set-top boxes. The AD853x family is
very stable and capable of driving heavy capacitive loads, such as
those found in LCDs.
The ability to swing rail-to-rail at the inputs and outputs enables
designers to buffer CMOS DACs, ASICs or other wide output
swing devices in single-supply systems.
The AD8531, AD8532 and AD8534 are specified over the
extended industrial (–40°C to +85°C) temperature range. The
AD8531 is available in SO-8 and SOT-23-5 packages. The
AD8532 is available in 8-lead plastic DIP, SO-8, 8-lead MSOP
and 8-lead TSSOP surface-mount packages. The AD8534 is
available in 14-lead plastic DIP, narrow SO-14 and 14-lead
TSSOP surface-mount packages. All TSSOP and SOT versions
are available in tape and reel only.
FEATURES
Single-Supply Operation: 2.7 Volts to 6 Volts
High Output Current: 6250 mA
Low Supply Current: 750 mA/Amplifier
Wide Bandwidth: 3 MHz
Slew Rate: 5 V/ms
No Phase Reversal
Low Input Currents
Unity Gain Stable
APPLICATIONS
Multimedia Audio
LCD Driver
ASIC Input or Output Amplifier
Headphone Driver
PIN CONFIGURATIONS
8-Lead SO
(R Suffix)
8-Lead SO
(R Suffix)
8-Lead TSSOP
(RU Suffix)
14-Lead Epoxy DIP
(N Suffix)
5-Lead SOT
(RT Suffix)
8-Lead Epoxy DIP
(N Suffix)
8-Lead MSOP
(RM Suffix)
14-Lead
Narrow-Body SO
(R Suffix)
14-Lead TSSOP
(RU Suffix)
AD8531/AD8532/AD8534–SPECIFICATIONS
ELECTRICAL CHARACTERISTICSSpecifications subject to change without notice.
(@ VS = +3.0 V, VCM = 1.5 V, TA = +258C unless otherwise noted)
ELECTRICAL CHARACTERISTICSNOISE PERFORMANCE
Specifications subject to change without notice.
AD8531/AD8532/AD8534
(@ VS = +5.0 V, VCM = 2.5 V, TA = +258C unless otherwise noted)
AD8531/AD8532/AD8534
ABSOLUTE MAXIMUM RATINGS1Supply Voltage (VS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .+7 V
Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . .GND to VS
Differential Input Voltage2 . . . . . . . . . . . . . . . . . . . . . . .–6 V
Storage Temperature Range
N, R, RM, RT, RU Package . . . . . . . . . .–65°C to +150°C
Operating Temperature Range
AD8531/AD8532/AD8534 . . . . . . . . . . . .–40°C to +85°C
Junction Temperature Range
N, R, RM, RT, RU Package . . . . . . . . . .–65°C to +150°C
Lead Temperature Range (Soldering, 60 sec) . . . . . . .+300°C
NOTESStresses above those listed under Absolute Maximum Ratings may cause perma-
nent damage to the device. This is a stress rating only; the functional operation of
the device at these or any other conditions above those indicated in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability.For supplies less than +6 volts, the differential input voltage is equal to –VS.
Figure 1.Output Voltage vs. Load. VS = –2.5 V, RL Is Connected to GND (0 V)
CAUTIONESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the AD8531/AD8532/AD8534 feature proprietary ESD protection circuitry, permanent
damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper
ESD precautions are recommended to avoid performance degradation or loss of functionality.
PACKAGE INFORMATIONNOTEqJA is specified for the worst case conditions, i.e., qJA is specified for device in socket
for P-DIP packages; qJA is specified for device soldered onto a circuit board for
surface-mount packages.
ORDERING GUIDE*Available in reels only.
Figure 2.Input Offset Voltage
Distribution
Figure 5.Input Bias Current vs.
Temperature
Figure 8.Output Voltage to Supply
Rail vs. Load Current
Figure 3.Input Offset Voltage
Distribution
Figure 6.Input Bias Current vs.
Common-Mode Voltage
Figure 9.Output Voltage to Supply
Rail vs. Load Current
Figure 4.Input Offset Voltage
vs. Temperature
Figure 7.Input Offset Current vs.
Temperature
Figure 10.Open-Loop Gain & Phase
vs. Frequency
AD8531/AD8532/AD8534–Typical Performance CharacteristicsFigure 11.Open-Loop Gain & Phase
vs. Frequency
Figure 14.Closed-Loop Output
Impedance vs. Frequency
Figure 17.Current Noise Density
vs. Frequency
Figure 12.Closed-Loop Output
Voltage Swing vs. Frequency
Figure 15.Voltage Noise Density
vs. Frequency
Figure 18.Common-Mode Rejec-
tion vs. Frequency
Figure 13.Closed-Loop Output
Voltage Swing vs. Frequency
Figure 16.Voltage Noise Density
vs. Frequency
Figure 19.Power Supply Rejection
vs. Frequency
POWER SUPPLY REJECTION – dB
FREQUENCY – Hz10k100k1M10M100
–20Figure 20.Power Supply Rejection
vs. Frequency
CAPACITANCE – pF100100001000
SMALL SIGNAL OVERSHOOT – %Figure 23.Small Signal Overshoot
vs. Load Capacitance
SUPPLY VOLTAGE – 6Volts
SUPPLY CURRENT/AMPLIFIER – mA
0.50Figure 26.Supply Current per
Amplifier vs. Supply Voltage
Figure 21.Small Signal Overshoot
vs. Load Capacitance
CAPACITANCE – pF100100001000
SMALL SIGNAL OVERSHOOT – %Figure 24.Small Signal Overshoot
vs. Load Capacitance
Figure 27.Small Signal Transient
Response
Figure 22.Small Signal Overshoot
vs. Load Capacitance
Figure 25.Supply Current per
Amplifier vs. Temperature
Figure 28.Small Signal Transient
Response
AD8531/AD8532/AD8534 Figure 29.Large Signal Transient
Response
Figure 30.Large Signal Transient
Response
APPLICATIONS
THEORY OF OPERATIONThe AD8531/AD8532/AD8534 is an all-CMOS, high output
current drive, rail-to-rail input/output operational amplifier.
This is the latest entry in Analog Devices’ expanding family of
single-supply devices for the multimedia and telecom market-
places. Its high output current drive and stability with heavy
capacitive loads makes the AD8531/AD8532/AD8534 an excel-
lent choice as a drive amplifier for LCD panels.
Figure 32 illustrates a simplified equivalent circuit for the AD8531/
AD8532/AD8534. Like many rail-to-rail input amplifier configu-
rations, it is comprised of two differential pairs, one n-channel
(M1–M2) and one p-channel (M3–M4). These differential pairs
are biased by 50 mA current sources, each with a compliance
limit of approximately 0.5 V from either supply voltage rail. The
differential input voltage is then converted into a pair of differ-
ential output currents. These differential output currents are
then combined in a compound folded-cascade second gain
stage (M5–M9). The outputs of the second gain stage at M8
and M9 provide the gate voltage drive to the rail-to-rail output
stage. Additional signal current recombination for the output
stage is achieved through the use of transistors M11–M14.
In order to achieve rail-to-rail output swings, the AD8531/
AD8532/AD8534 design employs a complementary common-
source output stage (M15–M16). However, the output voltage
swing is directly dependent on the load current, as the difference
between the output voltage and the supply is determined by the
AD8531/AD8532/AD8534’s output transistors on-channel
resistance (see Figures 8 and 9). The output stage also exhibits
voltage gain by virtue of the use of common-source amplifiers;
as a result, the voltage gain of the output stage (thus, the open-
loop gain of the device) exhibits a strong dependence to the total
load resistance at the output of the AD8531/AD8532/AD8534.
Figure 32.AD8531/AD8532/AD8534 Simplified Equivalent
Circuit
Short-Circuit ProtectionAs a result of the design of the output stage for maximum load
current capability, the AD8531/AD8532/AD8534 does not have
any internal short-circuit protection circuitry. Direct connection of
the AD8531/AD8532/AD8534’s output to the positive supply
in single-supply applications will destroy the device. In those
applications where some protection is needed, but not at the
expense of reduced output voltage headroom, a low value resis-
tor in series with the output, as shown in Figure 33, can be
used. The resistor, connected within the feedback loop of the
amplifier, will have very little effect on the performance of the
amplifier other than limiting the maximum available output volt-
age swing. For single +5 V supply applications, resistors less than
20 W are not recommended.
Figure 33.Output Short-Circuit Protection
Figure 31.No Phase Reversal
