MAX4291 Datasheet, PDF (10/16 Pages) Maxim Integrated Products – Ultra-Small, +1.8V, μPower, Rail-to-Rail I/O Op Amps

Ultra-Small, +1.8V, µPower,
Rail-to-Rail I/O Op Amps
OFFSET VOLTAGE vs. SUPPLY VOLTAGE
-450
T_A = +85°C
V_CM = V_CC/2
-500
-550
T_A = +25°C
-600
T_A = -40°C
-650
-700
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
SUPPLY VOLTAGE (V)
Figure 4. Offset Voltage vs. Supply Voltage
SUPPLY CURRENT vs. SUPPLY VOLTAGE
140
120
100
80
60
T_A = +25°C
T_A = -40°C
40
T_A = +85°C
20
0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
SUPPLY VOLTAGE (V)
Figure 5. Supply Current vs. Supply Voltage
Although the amplifiers are fully guaranteed over tem-
perature for operation down to a +1.8V single supply,
even lower voltage operation is possible in practice.
Figures 4 and 5 show the offset voltage and supply cur-
rent as a function of supply voltage and temperature.
Load-Driving Capability
The MAX4291/MAX4292/MAX4294 are fully guaranteed
over temperature and supply voltage range to drive a
maximum resistive load of 2kΩ to V_CC/2, although
heavier loads can be driven in many applications. The
rail-to-rail output stage of the amplifier can be modeled
as a current source when driving the load toward V_CC,
and as a current sink when driving the load toward V_EE.
The limit of this current source/sink varies with supply
voltage, ambient temperature, and lot-to-lot variations
of the units.
OUTPUT SOURCE CURRENT
vs. TEMPERATURE
30
V_CC = 5.5V
V_OH = V_CC - V_OUT
25 V_OH = 200mV
V_CC = 1.8V
V_OH = 200mV
20
V_CC = 5.5V
V_CC = 5.5V
V_OH = 100mV
15 VOH = 50mV V_CC = 1.8V
V_OH = 100mV _{VCC = 1.8V}
10
V_OH = 50mV
5
0
-55 -40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
Figure 6a. Output Source Current vs. Temperature
OUTPUT SINK CURRENT
vs. TEMPERATURE
18
V_CC = 5.5V
V_OL = V_OUT - V_EE
16 _{VOL = 200mV VCC = 5.5V}
14
V_OL = 50mV
V_CC = 1.8V
12 _{VCC = 5.5V}
V_OL = 200mV
10 VOL = 100mV _{VCC = 1.8V}
8
V_OL = 100mV VCC = 1.8V
V_OL = 50mV
6
4
2
0
-55 -40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
Figure 6b. Output Sink Current vs. Temperature
Figures 6a and 6b show the typical current source and
sink capabilities of the MAX4291/MAX4292/MAX4294
family as a function of supply voltage and ambient tem-
perature. The contours on the graph depict the output
current value, based on driving the output voltage to
within 50mV, 100mV, and 200mV of either power-sup-
ply rail.
For example, a MAX4291 running from a single +1.8V
supply, operating at T_A = +25°C can source 3.5mA to
within 100mV of V_CC and is capable of driving a 485Ω
load resistor to V_EE:
R_L =
(1.8V − 0.1V)
3.5mA
=
485Ω to V_EE
The same application can drive a 220kΩ load resistor
when terminated in V_CC/2 (+0.9V in this case).
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