|
|
PDF MAX4039 Data sheet ( Hoja de datos )
| Número de pieza | MAX4039 | |
| Descripción | Low IBIAS / +1.4V/800nA / Rail-to-Rail Op Amps with +1.2V Buffered Reference | |
| Fabricantes | Maxim Integrated | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MAX4039 (archivo pdf) en la parte inferior de esta página. Total 19 Páginas | ||
|
No Preview Available !
19-3142; Rev 2; 11/04
Low IBIAS, +1.4V/800nA, Rail-to-Rail Op Amps
with +1.2V Buffered Reference
General Description
The single MAX4036/MAX4037 and dual MAX4038/
MAX4039 operational amplifiers operate from a single
+1.4V to +3.6V (without reference) or +1.8V to +3.6V (with
reference) supply and consume only 800nA of supply
current per amplifier, and 1.1µA for the optional refer-
ence. The MAX4036/MAX4038 feature a common-mode
input voltage range from 0V to VDD - 0.4V at VDD = 1.4V.
The MAX4037/MAX4039 feature a 1.232V voltage refer-
ence capable of sourcing 100µA and sinking 20µA.
The MAX4036–MAX4039s’ rail-to-rail outputs drive 5kΩ
loads to within 25mV of the rails. Ultra-low supply current,
low operating voltage, and rail-to-rail outputs make the
MAX4036–MAX4039 ideal for use in single-cell lithium-ion
(Li+), or two-cell NiCd/NiMH/alkaline battery-powered
applications.
The MAX4036 is available in an SC70 package, the
MAX4037 in a SOT23 package, and the MAX4038/
MAX4039 in UCSP™, µMAX®, and TDFN packages. All
devices are specified over the -40°C to +85°C extended
temperature range.
Applications
Battery-Powered/Solar-Powered Systems
Portable Medical Instrumentation
Pagers and Cell Phones
Micropower Thermostats and Potentiostats
Electrometer Amplifiers
Remote Sensor Amplifiers
Active Badges
pH Meters
µMAX is a registered trademark and UCSP is a trademark of
Maxim Integrated Products, Inc.
Functional Diagram
OUTA
MAX4039
INA-
INA+
REF
REF
VSS
VDD
OUTB
INB-
INB+
Features
♦ Ultra-Low 800nA per Amplifier Supply Current
♦ Ultra-Low 1.4V Supply Voltage Operation (1.8V for
MAX4037/MAX4039)
♦ Rail-to-Rail Outputs Drive 5kΩ and 5000pF Load
♦ 1.232V ±0.5%, 120ppm/°C (max) Reference
(MAX4037/MAX4039)
♦ No External Reference Bypass Capacitor
Required
♦ No Phase Reversal for Overdriven Inputs
♦ Low 1.0pA (typ) Input Bias Current
♦ Low 200µV Input Offset Voltage
♦ Unity-Gain Stable
♦ Available in Tiny UCSP, SC70, SOT23, TDFN, and
µMAX Packages
Ordering Information
PART
TEMP RANGE PIN-
PACKAGE
TOP
MARK
MAX4036EXK-T -40°C to +85°C 5 SC70-5
AFR
MAX4037EUT-T -40°C to +85°C 6 SOT23-6
ABRX
MAX4038ETA
-40°C to +85°C 8 TDFN-EP* AGO
MAX4038EUA
-40°C to +85°C 8 µMAX
—
MAX4038EBL-T -40°C to +85°C 9 UCSP-9
AEG
MAX4039EBL-T
MAX4039ETB
-40°C to +85°C 9 UCSP-9
-40°C to +85°C 10 TDFN-EP*
AEH
AAN
MAX4039EUB
-40°C to +85°C 10 µMAX
—
*EP = Exposed paddle.
Pin Configurations and Selector Guide appear at end of
data sheet.
Typical Operating Circuit
3V
VDD
INA-
OUTA
INA+ MAX4039
REF
INB-
INB+
OUTB
VSS
SENSOR
ADC
THREE-ELECTRODE POTENTIOSTAT APPLICATION
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1 page  
Low IBIAS, +1.4V/800nA, Rail-to-Rail Op Amps
with +1.2V Buffered Reference
Typical Operating Characteristics
(VDD = 3V, VSS = VCM = 0V, RL to VDD/2, TA = +25°C, unless otherwise noted.)
MAX4036
SUPPLY CURRENT
vs. SUPPLY VOLTAGE AND TEMPERATURE
1.6
1.2 TA = +85°C TA = +25°C
MAX4037
SUPPLY CURRENT
vs. SUPPLY VOLTAGE AND TEMPERATURE
3.0
TA = +85°C TA = +25°C
2.5
2.0
MAX4038
SUPPLY CURRENT
vs. SUPPLY VOLTAGE AND TEMPERATURE
3.0
2.5 TA = +85°C TA = +25°C
2.0
0.8
0.4 TA = -40°C
1.5
1.0 TA = -40°C
0.5
1.5
1.0 TA = -40°C
0.5
0
1.4 1.8 2.2 2.6 3.0 3.4
SUPPLY VOLTAGE (V)
MAX4039
SUPPLY CURRENT
vs. SUPPLY VOLTAGE AND TEMPERATURE
5
4 TA = +85°C TA = +25°C
3
2
TA = -40°C
1
0
1.8
2.1 2.4 2.7 3.0 3.3
SUPPLY VOLTAGE (V)
3.6
OFFSET VOLTAGE
vs. COMMON-MODE VOLTAGE
1.0
0.8
0.6 VDD = 1.8V
VDD = 1.4V
0.4
VDD = 3.0V
0.2
0
1.4 1.8 2.2 2.6 3.0 3.4
SUPPLY VOLTAGE (V)
OFFSET VOLTAGE
vs. TEMPERATURE
0.30
0.20
0.10
0
-0.10
-0.20
0
1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)
0 -0.30
0 1 2 3 -40 -15 10 35 60 85
COMMON-MODE VOLTAGE (V)
TEMPERATURE (°C)
INPUT BIAS CURRENT
vs. TEMPERATURE
40
30
20
10 VCM = 3V
0
-10
-40
VCM = 0V
-15 10 35 60
TEMPERATURE (°C)
85
INPUT BIAS CURRENT
vs. COMMON-MODE VOLTAGE
40
30
TA = +85°C
20
10
0
0
TA = +25°C
0.5 1.0 1.5 2.0 2.5
COMMON-MODE VOLTAGE (V)
3.0
OP AMP POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
0
-10 AV = 1V/V
-20
-30
-40
-50
-60
-70
-80
-90
-100
10
100 1k
FREQUENCY (Hz)
10k
_______________________________________________________________________________________ 5
5 Page 
Low IBIAS, +1.4V/800nA, Rail-to-Rail Op Amps
with +1.2V Buffered Reference
Applications Information
Power-Supply Considerations
The MAX4036–MAX4039 operate from a single 1.4V
(MAX4036/MAX4038) or 1.8V (MAX4037/MAX4039) to
3.6V supply. A high amplifier power-supply rejection
ratio of 82dB and the excellent reference line regulation
allow the devices to be powered directly from a decay-
ing battery voltage, simplifying design and extending
battery life. The MAX4036–MAX4039 are ideally suited
for low-voltage battery-powered systems. The Typical
Operating Characteristics show the changes in supply
current and reference output as a function of supply
voltage.
Power-Up Settling Time
The MAX4036–MAX4039 typically require 0.25ms to
power-up. During this startup time, the output is inde-
terminate. The application circuit should allow for this
initial delay. See the Typical Operating Characteristics
for amplifier and reference settling time curves.
Driving Capacitive Loads: Op Amps
The MAX4036–MAX4039 amplifier(s) require no output
capacitor for stability, and are unity-gain stable for
loads up to 5000pF. Applications that require greater
capacitive-drive capability should use an isolation
resistor between the output and the capacitive load
(Figure 2). Note that this solution reduces the gain and
output voltage swing because RISO forms a voltage-
divider with the load resistor.
Crossover Distortion
The MAX4036–MAX4039 output stages are capable of
sourcing and sinking currents with orders of magnitude
greater than the stages’ quiescent current, which is
less than 1µA. This ability to drive heavy loads with
such a small quiescent current introduces crossover
MAX4038
RISO
RL
CL
AV
=
RL
RL
+ RISO
=1
INPUT VTHR
VTHF
OUTPUT
Figure 3. Hysteresis
VHB
VOH
VOL
distortion as the output stage passes between sinking
and sourcing. In the crossover regions, the output
impedance of the MAX4036–MAX4039 increases sub-
stantially, thereby changing the load-driving character-
istics. The distortion can be greatly reduced by
increasing the load resistance. For applications where
low load resistance is required, bias the load such that
the output current is always in one direction, to avoid
crossover distortion.
Reference Bypassing
The MAX4037/MAX4039 reference requires no external
capacitors.
Using the MAX4036–MAX4039 as a
Comparator
Although optimized for use as an operational amplifier,
the MAX4036–MAX4039 can be used as a rail-to-rail
I/O comparator (Figures 3, 4). External hysteresis can
be used to minimize the risk of output oscillation. The
positive feedback circuit, shown in Figure 4, causes the
input threshold to change when the output voltage
changes state.
Battery Monitoring Using the
MAX4037/MAX4039 and Hysteresis
The internal reference and low operating voltage of the
MAX4037/MAX4039 make the devices ideal for battery-
monitoring applications. Hysteresis can be set using
resistors as shown in Figure 4, and the following design
procedure:
1) Choose R3. The input bias current of IN_+ is under
100pA over temperature, so a current through R3
around 100nA maintains accuracy. The current
through R3 at the trip point is VREF / R3, or 100nA
for R3 = 12MΩ. 10MΩ is a good practical value.
2) Choose the hysteresis voltage (VHB), the voltage
between the upper and lower thresholds. In this
example, choose VHB = 50mV (see Figure 3).
Figure 2. Using a Resistor to Isolate a Capacitive Load from
the Op Amp
______________________________________________________________________________________ 11
11 Page | ||
| Páginas | Total 19 Páginas | |
| PDF Descargar | [ Datasheet MAX4039.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MAX403 | Micropower Op Amps | Maxim Integrated |
| MAX4032 | 5V / 6dB Video Buffer with Sync-Tip Clamp / Output Sag Correction / and 150nA Shutdown Current | Maxim Integrated |
| MAX4032EUT-T | 5V / 6dB Video Buffer with Sync-Tip Clamp / Output Sag Correction / and 150nA Shutdown Current | Maxim Integrated |
| MAX4032EXT-T | 5V / 6dB Video Buffer with Sync-Tip Clamp / Output Sag Correction / and 150nA Shutdown Current | Maxim Integrated |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |