Maxim MAX4199ESA Micropower, single-supply, rail-to-rail precision differential amplifier Datasheet

19-1445; Rev 0; 4/99
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
Rail-to-Rail®
The MAX4198/MAX4199 low-power,
differential amplifiers are ideal for single-supply applications
that benefit from a low 0.01% gain error. The MAX4198
is factory trimmed to a fixed gain of +1V/V, and the
MAX4199 is trimmed to a fixed gain of +10V/V. Capable
of operating from a single +2.7V to +7.5V supply or
from dual ±1.35V to ±3.75V supplies, they consume
only 42µA while achieving -3dB bandwidths of 175kHz
(MAX4198) and 45kHz (MAX4199). These amplifiers
feature a shutdown mode that reduces the supply current to 6.5µA.
The MAX4198/MAX4199 can drive 5kΩ loads to within
100mV from each rail. The standard differential amplifier configurations provide common-mode rejection of
90dB for the MAX4198 and 110dB for the MAX4199.
The input common-mode voltage range for the
MAX4198 extends 100mV Beyond-the-Rails™.
The MAX4198/MAX4199 are offered in a space-saving
8-pin µMAX package. For complete micropower, rail-torail instrumentation amplifiers, see the MAX4194–
MAX4197 data sheet.
Applications
Instrumentation Amplifier Building Block
Features
♦ Low 0.01% Gain Error
♦ High Common-Mode Rejection: 110dB (MAX4199)
♦ 10µV Input Offset Voltage (MAX4199)
30µV Input Offset Voltage (MAX4198)
♦ +2.7V to +7.5V Single-Supply Operation
♦ 42µA Supply Current
♦ 175kHz (MAX4198) and 45kHz (MAX4199)
-3dB Bandwidth
♦ 6.5µA Shutdown Current
♦ Rail-to-Rail Outputs Drive 5kΩ Loads
♦ Input Voltage Range Extends 100mV Beyond-theRails (MAX4198)
♦ Available in Space-Saving 8-Pin µMAX Package
Ordering Information
PART
TEMP. RANGE
PINPACKAGE
MAX4198EUA
-40°C to +85°C
8 µMAX
GAIN
(V/V)
1
Differential Voltage Amplifiers
MAX4198ESA
-40°C to +85°C
8 SO
1
Data-Acquisition Systems
MAX4199EUA
-40°C to +85°C
8 µMAX
10
Portable/Battery-Powered Equipment
MAX4199ESA
-40°C to +85°C
8 SO
10
Transducer Interface
Current-Sense Amplifiers
Pin Configuration
Functional Diagram
TOP VIEW
7 VCC
5 FB
IN- 2
25k
6 OUT
MAX4198
MAX4199
IN+
25k (250k)
REF 1
IN- 2
IN+
25k
3
25k (250k)
1
REF
4 VEE
( ) ARE FOR MAX4199 ONLY.
3
MAX4198
MAX4199
VEE 4
8
SHDN
7
VCC
6
OUT
5
FB
µMAX/SO
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
Beyond-the-Rails is a trademark of Maxim Integrated Products.
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.
MAX4198/MAX4199
General Description
MAX4198/MAX4199
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (VCC to VEE)..................................................+8V
All Other Pins to GND ......................(VEE - 0.3V) to (VCC + 0.3V)
Output Short Circuit Duration (to VCC or VEE)............Continuous
Continuous Power Dissipation (TA = +70°C)
SO (derate 9.09mW/°C above +70°C) ..........................471mW
µMAX (derate 4.1mW/°C above +70°C) .......................330mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range ............................ -65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS—MAX4198 (+5V Supply)
(VCC = +5V, VEE = 0V, RL = 25kΩ tied to VCC / 2, VREF = VCC / 2, V SHDN = VCC - 1.5V, typical values are at T A = +25°C,
TA = TMIN to TMAX, unless otherwise noted.) (Note 1)
PARAMETER
Supply Voltage Range
(Note 2)
SYMBOL
VCC
Input Offset Voltage
VOS
Input Offset Voltage Drift
TCO
Input Resistance
RIN
Input Voltage Range
VIN
DC Common-Mode Rejection
CMRDC
AC Common-Mode Rejection
CMRAC
Power-Supply Rejection
Input Noise Voltage
PSR
CONDITIONS
Single supply
Dual supply
TA = +25°C,
VCM = VCC / 2
TA = TMIN to TMAX,
VCM = VCC / 2
Nonlinearity
2
±3.75
±500
±1000
±750
±2300
±5
±20
±30
±100
IN- differential-mode
25
Common-mode
50
VCM = VEE - 0.1V
to VCC + 0.1V
90
MAX4198EUA
70
90
Sink/source
VEE + 0.1V ≤
VOUT ≤ VCC 0.1V
RL = 25kΩ, VEE + 0.1V ≤
VOUT ≤ VCC - 0.1V
RL = 5kΩ, VEE + 0.2V ≤
VOUT ≤ VCC - 0.2V
90
UNITS
V
µV
µV/°C
kΩ
VCC + 0.1
74
VCM = VEE - 0.1 to VCC + 0.1V,
f = 60Hz, f = 120Hz
+2.7V ≤ VCC ≤ +7.5V, VCM = +1.5V,
VREF = +1.5V, RL = 25kΩ to +1.5V
f = 10Hz
f = 100Hz
f = 10kHz
f = 0.1Hz to 10Hz
VCM = VCC / 2,
TA = +25°C
VEE - 0.1
MAX4198ESA
RL = 5kΩ, ±10mV input overdrive
Gain Temperature Coefficient
±1.35
±0.5
±1
50
Guaranteed by CMR test
MAX
7.5
MAX4198ESA
MAX4198EUA
IN+ differential-mode
RL = 25kΩ, ±10mV input overdrive
Gain Error
TYP
2.7
MAX4198ESA
MAX4198EUA
MAX4198ESA
MAX4198EUA
Output Voltage Swing
Short-Circuit Current
MIN
V
dB
90
dB
115
dB
120
60
58
7.8
VEE + 0.1 VEE + 0.03 to
to VCC - 0.1 VCC - 0.03
VEE + 0.2 VEE + 0.1 to
to VCC - 0.2 VCC - 0.1
±5.5
nV√Hz
µVRMS
V
mA
±0.01
±0.1
±0.01
±0.1
MAX4198ESA
±0.2
±3
MAX4198EUA
±0.65
±6
%
ppm/°C
VEE + 0.1V ≤ VOUT ≤ VCC - 0.1V
±0.0003
_______________________________________________________________________________________
%
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
(VCC = +5V, VEE = 0V, RL = 25kΩ tied to VCC / 2, VREF = VCC / 2, V SHDN = VCC - 1.5V, typical values are at T A = +25°C,
TA = TMIN to TMAX, unless otherwise noted.) (Note 1)
PARAMETER
Capacitive Load Stability
-3dB Bandwidth
SYMBOL
CONDITIONS
MIN
TYP
CL
BW-3dB
MAX
UNITS
690
pF
VOUT ≤ 0.1Vp-p, VCM = VCC / 2
175
kHz
Slew Rate
SR
VOUT = 2Vp-p step
0.07
V/µs
Settling Time to 0.1%
ts
VOUT = 2Vp-p step
34
µs
0.001
%
Total Harmonic Distortion
Supply Current
Shutdown Supply Current
THD
VOUT = 2Vp-p, f = 1kHz
ICC
VCM = VCC / 2, VIN+ = VIN-
45
55
µA
V SHDN = VIL
6.5
12
µA
ISHDN
Input Logic Voltage High (Note 3)
VIH
Input Logic Voltage Low (Note 3)
VIL
VCC - 1.5
V
VCC - 2.5
V
SHDN Input Bias Current
V SHDN = VCC - 1.5V or V SHDN = VEE
Enable/Disable Settling Time
V SHDN = VCC - 2.5V to VCC - 1.5V,
VOUT = 3.5V, settled to within 0.1%
28
µs
VOUT = 3.5V, settled to within 0.1%
800
µs
tON/OFF
Power-Up Delay
-0.1
0.1
µA
ELECTRICAL CHARACTERISTICS—MAX4198 (+3V Supply)
(VCC = +3V, VEE = 0V, RL = 25kΩ tied to VCC / 2, VREF = VCC / 2, V SHDN = VCC - 1.5V, typical values are at TA = +25°C, TA = TMIN
to TMAX, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
Input Offset Voltage
VOS
Input Offset Voltage Drift
TCO
Input Voltage Range
VIN
DC Common-Mode Rejection
CMRDC
CONDITIONS
TYP
MAX
MAX4198ESA
MAX4198EUA
MAX4198ESA
MAX4198EUA
±35
±100
MAX4198ESA
MAX4198EUA
Guaranteed by CMR test
MAX4198ESA
VCM = VEE - 0.1
to VCC + 0.1
MAX4198EUA
±0.5
±1.0
±600
±1100
±850
±2400
±5.0
±20
VCC + 0.1
TA = +25°C,
VCM = VCC / 2
TA = TMIN to TMAX,
VCM = VCC / 2
RL = 25kΩ, ±10mV input overdrive
Output Voltage Swing
RL = 5kΩ, ±10mV input overdrive
Short-Circuit Current
Sink/source
Gain Error
RL = 25kΩ, VEE + 0.1V ≤
VCM = VCC / 2, VOUT ≤ VCC - 0.1V
TA = +25°C
RL = 5kΩ, VEE + 0.2V ≤
VOUT ≤ VCC - 0.2V
VEE + 0.1V ≤
VOUT ≤ VCC 0.1V
Gain Temperature Coefficient
Supply Current
ICC
Shutdown Supply Current
MIN
VEE - 0.1
74
90
70
90
VEE + 0.1 VEE + 0.03 to
to VCC - 0.1 VCC - 0.03
VEE + 0.2 VEE + 0.1 to
to VCC - 0.2 VCC - 0.1
±4.5
±0.01
±0.1
±0.01
±0.1
MAX4198ESA
±0.2
±3
MAX4198EUA
±0.65
±6
VIH
Input Logic Low Voltage (Note 3)
VIL
µV
µV/°C
V
dB
V
mA
%
ppm/°C
VCM = VCC / 2, VDIFF = 0
I SHDN
Input Logic High Voltage (Note 3)
UNITS
42
µA
6.5
µA
VCC - 1.5
V
VCC - 2.5
V
_______________________________________________________________________________________
3
MAX4198/MAX4199
ELECTRICAL CHARACTERISTICS—MAX4198 (+5V Supply) (continued)
MAX4198/MAX4199
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
ELECTRICAL CHARACTERISTICS—MAX4199 (+5V Supply)
(VCC = +5V, VEE = 0V, RL = 25kΩ tied to VCC / 2, VREF = VCC / 2, V S HDN = VCC - 1.5V, typical values are at TA = +25°C,
TA = TMIN to TMAX, unless otherwise noted.) (Note 1)
PARAMETER
Supply Voltage Range (Note 2)
SYMBOL
VCC
Input Offset Voltage
VOS
Input Offset Voltage Drift
TCO
Input Resistance
RIN
CONDITIONS
Single supply
Dual supply
TA = +25°C,
VCM = VCC / 2
TA = TMIN to TMAX,
VCM = VCC / 2
MAX4199EUA
MAX4199ESA
MAX4199EUA
MAX4199ESA
MAX4199EUA
25
Common-mode
275
CMRDC
VCM = VEE - 0.1V
to VCC - 1.0V
AC Common-Mode Rejection
CMRAC
VCM = VEE - 0.1V to VCC - 1.0V, f = 60Hz
Guaranteed by CMR test
84
110
80
110
RL = 25kΩ, ±10mV input overdrive
Output Voltage Swing
RL = 5kΩ, ±10mV input overdrive
Short-Circuit Current
Sink/source
Gain Error
RL = 25kΩ, VEE + 0.1V ≤
VCM = VCC / 2, VOUT ≤ VCC - 0.1V
TA = +25°C
RL = 5kΩ, VEE + 0.2V ≤
VOUT ≤ VCC - 0.2V
Capacitive Load Stability
-3dB Bandwidth
µV
µV/°C
V
110
dB
120
dB
60
40
38
6.6
VEE + 0.1 VEE + 0.02 to
to VCC - 0.1 VCC - 0.02
VEE + 0.2 VEE + 0.1 to
to VCC - 0.2 VCC - 0.1
nV√Hz
µVRMS
V
mA
±0.01
±0.3
±0.01
±0.3
MAX4199ESA
±1
±5
MAX4199EUA
±2
±10
%
ppm/°C
CL
BW-3dB
V
dB
±5.5
VEE + 0.1V ≤ VOUT ≤ VCC - 0.1V
Nonlinearity
90
UNITS
kΩ
VCC - 1.0
MAX4199EUA
+2.7V ≤ VCC ≤ +7.5V, VCM = +1.5V,
VREF = +1.5V, RL = 25kΩ to +1.5V
VEE + 0.1V ≤
VOUT ≤ VCC 0.1V
VEE - 0.1
MAX4199ESA
f = 10Hz
f = 100Hz
f = 10kHz
f = 0.1Hz to 10Hz
Gain Temperature Coefficient
7.5
±3.75
±300
±600
±500
±1475
±3
±15
±10
±100
IN- differential mode
DC Common-Mode Rejection
Input Noise Voltage
MAX
±0.25
±0.75
275
VIN
PSR
TYP
2.7
±1.35
MAX4199ESA
MAX4199EUA
IN+ differential mode
Input Voltage Range (Note 2)
Power-Supply Rejection
MIN
±0.0003
%
600
pF
VOUT ≤ 0.1Vp-p, VCM = VCC / 2
45
kHz
Slew Rate
SR
VOUT = 2Vp-p
0.1
V/µs
Settling Time to 0.1%
ts
VOUT = 2Vp-p step
37
µs
0.001
%
Total Harmonic Distortion
Supply Current
Shutdown Supply Current
4
THD
VOUT = 2Vp-p, f = 1kHz
ICC
VCM = VCC / 2, VIN+ = VIN-
45
55
µA
V SHDN = VIL
6.5
12
µA
I SHDN
_______________________________________________________________________________________
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
(VCC = +5V, VEE = 0V, RL = 25kΩ tied to VCC / 2, VREF = VCC / 2, V S HDN = VCC - 1.5V, typical values are at TA = +25°C,
TA = TMIN to TMAX, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
Input Logic Voltage High
(Note 3)
VIH
Input Logic Voltage Low
(Note 3)
VIL
CONDITIONS
MIN
TYP
MAX
UNITS
VCC - 1.5
V
VCC - 2.5
V
SHDN Input Bias Current
V SHDN = VCC - 1.5V or V SHDN = VEE
Enable/Disable Settling Time
V SHDN = VCC - 2.5V to VCC - 1.5V,
VOUT = 3.5V, settled to within 0.1%
35
µs
VOUT = 3.5V, settled to within 0.1%
800
µs
tON/OFF
Power-Up Delay
-0.1
0.1
µA
ELECTRICAL CHARACTERISTICS—MAX4199 (+3V Supply)
(V CC = +3V, V EE = 0V, R L = 25kΩ tied to V CC / 2, V REF = V CC / 2, V S HDN = V CC - 1.5V, values are at T A = +25°C,
TA = TMIN to TMAX, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
Input Offset Voltage
VOS
Input Offset Voltage Drift
TCO
Input Voltage Range
VIN
DC Common-Mode Rejection
CMRDC
CONDITIONS
TA = +25°C,
VCM = VCC / 2
TA = TMIN to TMAX,
VCM = VCC / 2
MAX4199ESA
MAX4199EUA
MAX4199ESA
MAX4199EUA
MAX4199ESA
MAX4199EUA
Guaranteed by CMR test
VCM = VEE - 0.1
to VCC - 1.1
±0.25
±0.75
VEE - 0.1
110
110
Sink/source
Gain Error
RL = 25kΩ, VEE + 0.1V ≤
VCM = VCC / 2, VOUT ≤ VCC - 0.1V
TA = +25°C
RL = 5kΩ, VEE + 0.2V ≤
VOUT ≤ VCC - 0.2V
ICC
VIH
Input Logic Low Voltage (Note 3)
VIL
UNITS
µV
µV/°C
V
dB
VEE + 0.1 VEE + 0.02 to
to VCC - 0.1 VCC - 0.02
VEE + 0.2 VEE + 0.1 to
to VCC - 0.2 VCC - 0.1
±4.5
V
mA
±0.01
±0.3
±0.01
±0.3
MAX4199ESA
±1
±5
MAX4199EUA
±2
±10
%
ppm/°C
VCM = VCC / 2, VDIFF = 0
I SHDN
Input Logic High Voltage (Note 3)
±400
±700
±600
±1675
±5
±15
VCC - 1.1
80
Short-Circuit Current
Shutdown Supply Current
±15
±100
84
RL = 5kΩ, ±10mV input overdrive
Supply Current
MAX
MAX4199EUA
Output Voltage Swing
VEE + 0.1V ≤
VOUT ≤ VCC 0.1V
TYP
MAX4199ESA
RL = 25kΩ, ±10mV input overdrive
Gain Temperature Coefficient
MIN
42
µA
6.5
µA
VCC - 1.5
V
VCC - 2.5
V
Note 1: The MAX4198EUA and the MAX4199EUA are 100% production tested at +25°C. All temperature limits are guaranteed
by design.
Note 2: Guaranteed by PSR test.
Note 3: When shutdown input is at logic high, the part is active; when at logic low, the part is in shutdown.
_______________________________________________________________________________________
5
MAX4198/MAX4199
ELECTRICAL CHARACTERISTICS—MAX4199 (+5V Supply) (continued)
Typical Operating Characteristics
(VCC = +5V, VEE = 0V, RL = 25kΩ to VCC / 2, V SHDN = VCC - 1.5V, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p,
TA = +25°C, unless otherwise noted.)
MAX4198
SMALL-SIGNAL GAIN vs. FREQUENCY
2
MAX4198
42
3
2
1
0
GAIN (dB)
MAX4199
41
40
39
-1
-2
0
-1
-2
-3
-3
37
-4
-4
36
-5
-5
35
-6
-15
10
35
TEMPERATURE (°C)
60
-6
0.1k
85
POWER-SUPPLY REJECTION vs.
FREQUENCY
10k
100k
FREQUENCY (Hz)
1M
0.1k
0
-20
600
-80
-110
-100
VOLTAGE (mV)
CMR (dB)
-90
MAX4198
100
1k
10k
100k
10
100
1k
10k
100k
FREQUENCY (Hz)
COMMON-MODE REJECTION vs.
TEMPERATURE
INPUT OFFSET VOLTAGE
vs. TEMPERATURE
-80
MAX4198
-90
-100
MAX4199
MAX4199
VOH - VCC
MAX4198
0.1
1M
1
10
100
LOAD (kΩ)
GAIN ERROR vs. TEMPERATURE
0.008
MAX4198toc08
100
INPUT OFFSET VOLTAGE (µV)
MAX4198toc07
-70
0
-200
-1000
FREQUENCY (Hz)
-60
200
-800
MAX4199
0.006
0.004
0.002
50
GAIN ERROR (%)
10
VOL - VEE
MAX4198
-600
-120
1
1M
-400
MAX4199
-130
MAX4199
800
400
-60
100k
1000
-40
-70
10k
OUTPUT VOLTAGE HIGH AND LOW vs.
LOAD RESISTANCE
MAX4198
-50
1k
FREQUENCY (Hz)
MAX4198toc05
-30
1k
COMMON-MODE REJECTION vs.
FREQUENCY
MAX4198toc04
-10
PSR (dB)
1
38
-40
MAX4198toc03
3
MAX4199
0
MAX4198
MAX4198toc09
SUPPLY CURRENT (µA)
43
NORMALIZED GAIN (dB)
44
MAX4198toc06
MAX4198toc01
45
MAX4199
SMALL-SIGNAL GAIN vs. FREQUENCY
MAX4198toc02
SUPPLY CURRENT vs. TEMPERATURE
CMR (dB)
MAX4198/MAX4199
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
0
-0.002
MAX4199
-0.004
-0.006
-0.008
-50
MAX4198
-0.010
-110
-0.012
-40
6
-0.014
-100
-120
-15
10
35
TEMPERATURE (°C)
60
85
-40
-15
10
35
TEMPERATURE (°C)
60
85
-40
-15
10
35
TEMPERATURE (°C)
_______________________________________________________________________________________
60
85
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
VOLTAGE NOISE DENSITY
vs. FREQUENCY
TOTAL HARMONIC DISTORTION
VOLTAGE NOISE vs. FREQUENCY
THD + VOLTAGE NOISE (%)
1k
MAX4198
100
SMALL-SIGNAL PULSE RESPONSE
MAX4198toc12
MAX4198toc11
1.000
MAX4198toc10
VOLTAGE NOISE DENSITY (nV/√Hz)
10k
INPUT
50mV/div
0.100
0.010
MAX4199
OUTPUT
50mV/div
0.001
MAX4198
MAX4199
10
1
10
100
1k
10k
100k
0
100
1k
50µs/div
10k
FREQUENCY (Hz)
FREQUENCY (Hz)
MAX4199
SMALL-SIGNAL PULSE RESPONSE
MAX4199
LARGE-SIGNAL PULSE RESPONSE
MAX4198
LARGE-SIGNAL PULSE RESPONSE
MAX4198toc13
MAX4198toc15
MAX4198toc14
INPUT
5mV/div
INPUT
500mV/div
INPUT
50mV/div
OUTPUT
50mV/div
OUTPUT
500mV/div
OUTPUT
500mV/div
50µs/div
50µs/div
50µs/div
MAX4198
SMALL-SIGNAL PULSE RESPONSE
WITH CAPACITIVE LOAD
MAX4198
SMALL-SIGNAL PULSE RESPONSE
WITH EXCESSIVE CAPACITIVE LOAD
MAX4198
SMALL-SIGNAL PULSE RESPONSE WITH
EXCESSIVE CAPACITIVE LOAD
AND ISOLATION RESISTOR
MAX4198toc16
MAX4198toc18
MAX4198toc17
CL = 690pF
CL = 1060pF
RISO = 50Ω
CL = 1060pF
RISO = 0Ω
OUTPUT
50mV/div
OUTPUT
50mV/div
OUTPUT
50mV/div
50µs/div
INPUT
50mV/div
INPUT
50mV/div
INPUT
50mV/div
50µs/div
50µs/div
_______________________________________________________________________________________
7
MAX4198/MAX4199
Typical Operating Characteristics (continued)
(VCC = +5V, VEE = 0V, RL = 25kΩ to VCC / 2, V SHDN = VCC - 1.5V, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p,
TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VCC = +5V, VEE = 0V, RL = 25kΩ to VCC / 2, V SHDN = VCC - 1.5V, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p,
TA = +25°C, unless otherwise noted.)
MAX4199
SMALL-SIGNAL PULSE RESPONSE
WITH CAPACITIVE LOAD
MAX4199
SMALL-SIGNAL PULSE RESPONSE WITH
EXCESSIVE CAPACITIVE LOAD
AND ISOLATION RESISTOR
MAX4199
SMALL-SIGNAL PULSE RESPONSE WITH
EXCESSIVE CAPACITIVE LOAD
MAX4198toc19
MAX4198toc20
MAX4198toc21
INPUT
5mV/div
INPUT
5mV/div
CL = 590pF
INPUT
5mV/div
CL = 760pF
RISO = 75Ω
CL = 760pF
RISO = 0Ω
OUTPUT
50mV/div
OUTPUT
50mV/div
OUTPUT
50mV/div
50µs/div
MAX4198
TIME EXITING SHUTDOWN
50µs/div
MAX4198 HISTOGRAM
(VOS BASED ON 200 UNITS)
MAX4199
TIME EXITING SHUTDOWN
MAX4198toc22
MAX4198toc23
60
50
INPUT
(SHDN PIN)
500mV/div
40
COUNT
INPUT
(SHDN PIN)
500mV/div
OUTPUT
500mV/div
MAX4198toc24
50µs/div
OUTPUT
500mV/div
30
20
10
0
10µs/div
-300 -240 -180 -120 -60
10µs/div
0
60 120 180 240 300
VOS (µV)
100
90
80
140
120
70
60
100
60
COUNT
COUNT
80
50
40
40
80
60
30
40
20
20
20
10
0
0
0
-300 -240 -180 -120 -60
0
60 120 180 240 300
VOS (µV)
8
160
MAX4198toc26
100
MAX4198toc25
120
MAX4199 HISTOGRAM
(GAIN ACCURACY BASED ON 280 UNITS)
MAX4198 HISTOGRAM
(GAIN ACCURACY BASED ON 200 UNITS)
MAX4198toc27
MAX4199 HISTOGRAM
(VOS BASED ON 280 UNITS)
COUNT
MAX4198/MAX4199
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
-0.08 -0.06 -0.04 -0.02 0
0.02 0.04 0.06 0.08
GAIN ERROR (%)
-0.24 -0.18 -0.12 -0.06
0 -0.06 0.12 0.18 0.24
GAIN ERROR (%)
_______________________________________________________________________________________
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
MAX4198
INPUT COMMON-MODE RANGE vs.
SUPPLY VOLTAGE
INPUT COMMON-MODE VOLTAGE (V)
VREF = VCC/2
6.5
5.5
4.5
3.5
2.5
1.5
0.5
8.5
INPUT COMMON-MODE VOLTAGE (V)
MAX4198toc28
7.5
MAX4198toc29
MAX4199
INPUT COMMON-MODE RANGE vs.
SUPPLY VOLTAGE
VREF = VCC/2
7.5
6.5
5.5
4.5
3.5
2.5
1.5
0.5
-0.5
-0.5
2
3
4
5
6
7
2
8
SUPPLY VOLTAGE (V)
3
4
5
6
7
8
SUPPLY VOLTAGE (V)
Pin Description
PIN
NAME
FUNCTION
1
REF
Reference Voltage Input. Offsets output voltage.
2
IN-
Inverting Input
3
IN+
Noninverting Input
4
VEE
Negative Supply Voltage
5
FB
Feedback Resistor. Can be used as a sense input.
6
OUT
Amplifier Output
7
VCC
Positive Supply Voltage
8
SHDN
Shutdown Control. Shutdown threshold is referenced to VCC. When pulled 2.5V below VCC, part
is in shutdown.
_______________Detailed Description
The MAX4198/MAX4199 are precision low-power differential amplifiers with factory-trimmed internal gain-setting resistors. The MAX4198 is trimmed to a gain of
+1V/V and the MAX4199 is trimmed to a gain of +10V/V.
Input Stage
The Functional Diagram shows the internal structure of
the MAX4198/MAX4199. Although the resistors are precision matched, their absolute value varies by ±25%.
The typical input impedance for the MAX4198 is 50kΩ
for the noninverting input and 25kΩ for the inverting
input. The typical input impedance for the MAX4199 is
275kΩ for the noninverting input and 25kΩ for the
inverting input.
The common-mode inputs of the internal op amp can
range from VEE to (VCC - 1.1V). Although the inputs to
the internal op amp are not rail-to-rail, the internal resistors form a voltage divider that extends the input common-mode range beyond-the-rails for the MAX4198.
The overall input range of the MAX4198 extends 100mV
beyond-the-rails without adversely affecting commonmode rejection or undergoing phase reversal (VCC =
5V). The MAX4199 input common-mode range extends
from 100mV below the negative rail to (VCC - 1V) (see
the Input Common-Mode Voltage Range vs. Supply
Voltage graph in the Typical Operating Characteristics).
_______________________________________________________________________________________
9
MAX4198/MAX4199
Typical Operating Characteristics (continued)
(VCC = +5V, VEE = 0V, RL = 25kΩ to VCC / 2, V SHDN = VCC - 1.5V, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p,
TA = +25°C, unless otherwise noted.)
MAX4198/MAX4199
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
Rail-to-Rail Output Stage
The MAX4198/MAX4199 output stage incorporates a
common-source rail-to-rail structure which maximizes the
dynamic range of the differential amplifier. The output
can swing to within 100mV from each rail with a 5kΩ load
to VCC / 2 (see Typical Operating Characteristics).
IN-
FB
VCC
Shutdown Mode
The MAX4198/MAX4199 have an active-low shutdown
input. SHDN input logic thresholds are referenced to
VCC, not to GND. Pulling SHDN 2.5V below the positive
rail places the amplifiers in a 12µA (max) shutdown
mode. The MAX4198/MAX4199 exit or enter shutdown
in 35µs. In shutdown, the OUT pin is high-impedance.
RISO
OUT
MAX4198
MAX4199
OUTPUT
RL
CL
VEE
INPUT
IN+
REF
Applications Information
Driving Capacitive Loads
The MAX4198/MAX4199 are relatively immune to oscillations caused when driving large capacitive loads.
Although heavy load capacitance increases transient ringing, sustained oscillations typically don’t occur for loads
under 600pF (see Pulse Response with Capacitive Load
in the Typical Operating Characteristics). Applications that
require driving higher capacitive loads can isolate the output capacitance using a 15Ω to 100Ω resistor between the
amplifier output and the load (Figure 1). Although adding
an isolation resistor dampens the response enough to prevent oscillations, it does so at the expense of bandwidth
and DC accuracy.
Figure 1. Dual-Supply, Capacitive-Load Driving Circuit
VA
IN-
FB
VCC
OUT
MAX4198
MAX4199
VOUT = (VB - VA)
(MAX4198)
VOUT = 10 (VB - VA)
(MAX4199)
VEE
VB
IN+
Power Supply Considerations
The MAX4198/MAX4199 operate from single +2.7V to
+7.5V supplies or from dual ±1.35V to ±3.75V supplies,
and they consume only 45µA of supply current.
Excellent power-supply rejection permits the amplifiers
to be operated directly from a decaying 3V cell without
excessive error. To maximize AC performance, the supply must be bypassed with a 0.1µF ceramic capacitor
to ground that must be as close as possible to the pin.
If dual supplies are used, bypass both supply pins with
0.1µF to ground.
VOUT
REF
Figure 2. Standard Difference Amplifier
VA
IN-
FB
VCC
Application Circuits
Differential amplifiers can be used in single-ended and
other amplifier applications. Figures 2 through 6 show
the MAX4198/MAX4199 in different configurations. The
internally trimmed and matched resistors offer convenience and have a distinct advantage over external
resistors. These amplifiers are not compensated for single-ended unity gain; therefore, IN- should not be connected to OUT or left unconnected.
OUT
MAX4198
MAX4199
VOUT = -VA (MAX4198)
VEE
VOUT = -10VA (MAX4199)
IN+
REF
Figure 3. Precision Inverting Buffer
10
VOUT
______________________________________________________________________________________
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
also be used as an instrumentation amplifier building
block. The circuit of Figure 7 takes advantage of the
10pA (max), 0.1pA (typ) bias current of the MAX406A
to form an instrumentation amplifier similar to the
MAX4194 family, except with lower input bias currents.
The MAX406A's low 1.2µA supply current maintains a
low overall supply current.
VCC
IN+
IN-
2
5
FB
FB
VCC
VCC
6
IN+
VA
VOUT
INOUT
VOUT
3
VEE
REF
OUT
VA
VOUT = 2VA
VOUT = -VA
1
MAX4198
MAX4198
REF
Figure 4. Precision Gain of Two Amplifiers
Figure 5. Single-Supply Inverting Amplifier Biased at VCC / 2
VA
A1
VA
2
IN-
FB 5
IN-
VCC
6
OUT
MAX4544
6
NO
5
3
COM IN+
4
NC
FB
R2
R1
VOUT
OUT
VOUT
R2
VEE
1
REF
IN 1
MAX4198
LOGIC
VOUT
IN
-VA
0
+VA
1
IN+
A2
VB
NOTE: MAX4544 PINOUT FOR 6-PIN SOT23-6
Figure 6. Digitally Controlled Precision Gain of ±1 Amplifier
A1, A2 = MAX406A
REF
MAX4198
VOUT = (1 + 2R2 / R1) (VB - VA)
Figure 7. Ultra-Low Input Bias Current (0.1pA) Instrumentation
Amplifiers with 47µA Supply-Current Consumption
______________________________________________________________________________________
11
MAX4198/MAX4199
Instrumentation Amplifier Applications
For applications that require a complete low-power
instrumentation amplifier, refer to the MAX4194–
MAX4197 data sheet. Some differential to single-ended
voltage amplifier applications that don’t require a high
input impedance can use the MAX4198/MAX4199 for
gains of +1V/V or +10V/V. The MAX4198/MAX4199 can
Chip Information
TRANSISTOR COUNT: 250
SUBSTRATE CONNECTED TO VEE
Package Information
8LUMAXD.EPS
MAX4198/MAX4199
Micropower, Single-Supply, Rail-to-Rail
Precision Differential Amplifiers
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1999 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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