TC1026CEUA Microchip Technology, TC1026CEUA Datasheet - Page 5

• Manufacturer Part Number: TC1026CEUA
• Description: IC COMPARATOR OPAMP/REF 8MSOP
• Manufacturer: Microchip Technology
• Type: Amplifier, Comparator, Referencer

Specifications of TC1026CEUA

• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Applications: General Purpose
• Mounting Type: Surface Mount
• Number Of Channels: 1 Channel
• Output Type: Push-Pull
• Response Time: 4 us
• Offset Voltage (max): 1.5 mV
• Input Bias Current (max): 100 pA
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 1.8 V
• Supply Current (max): 18 uA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3.0
The TC1026 is one of a series of very low power, linear
building block products targeted at low voltage, single
supply applications. The TC1026 minimum operating
voltage is 1.8V, and typical supply current is only 12µA.
It combines a comparator, an op amp and a voltage
reference in a single package.
3.1
The TC1026 contains one comparator. The compara-
tor’s input range extends beyond both supply voltages
by 200mV and the outputs will swing to within several
millivolts of the supplies depending on the load current
being driven. The inverting input is internally connected
to the output of the reference.
The comparator exhibits propagation delay and supply
current which are largely independent of supply
voltage. The low input bias current and offset voltage
make it suitable for high impedance precision
applications.
3.2
The TC1026 contains one rail-to-rail op amp. The
amplifier’s input range extends beyond both supplies
by 200mV and the outputs will swing to within several
millivolts of the supplies depending on the load current
being driven.
The amplifier design is such that large signal gain, slew
rate and bandwidth are largely independent of supply
voltage. The low input bias current and offset voltage of
the TC1026 make it suitable for precision applications.
3.3
A 2.0% tolerance, internally biased, 1.20V bandgap
voltage reference is included in the TC1026. It has a
push-pull output capable of sourcing and sinking at
least 50µA.
©
2002 Microchip Technology Inc.
DETAILED DESCRIPTION
Comparator
Operational Amplifier
Voltage Reference
4.0
The TC1026 lends itself to a wide variety of
applications, particularly in battery powered systems. It
typically finds application in power management,
processor supervisory and interface circuitry.
4.1
Hysteresis can be set externally with three resistors
using positive feedback techniques (see Figure 4-1).
The design procedure for setting external comparator
hysteresis is as follows:
1.
2.
3.
EQUATION 4-1:
4.
5.
EQUATION 4-2:
6.
EQUATION 4-3:
EQUATION 4-4:
V
Choose the feedback resistor R
input bias current of the comparator is at most
100pA, the current through R
100nA (i.e., 1000 times the input bias current)
and retain excellent accuracy. The current
through R
R
Determine the hysteresis voltage (V
the upper and lower thresholds.
Calculate R
Choose the rising threshold voltage for V
(V
Calculate R
Verify the threshold voltages with these
formulas:
V
SRC
SRC
C
V
THR
where V
TH R
TYPICAL APPLICATIONS
External Hysteresis (Comparator)
rising:
).
falling:
R
V
=
B
THF
C
=
(
A
B
at the comparator’s trip point is V
R
V
as follows:
as follows:
R
---------------------------------------------------------- -
is a stable reference voltage.
=
R


) R
-------------------- -
V
(
A
V
V
R
THR
=
A
THR
×
)
R
R


–
C
A
------ -
R
1


1


A


---------- -
V
V
–


R
------------------------ -
D D
------ -
R
H Y
+
1
A
A




R
×
TC1026
–
-------
R
C
C
1
V
-------
R
B
1
DD
DS21725B-page 5


can be set to
C
C
+
HY


. Since the


) between
-------
R
1
C


SRC
R
/