SGS-THOMSON Microelectronics TC1026CEOA, TC1026 Datasheet

SOP

TC1026

Linear Building Block – Low Power Comparator with

Op Amp and Voltage Reference

Features

• Combines Low-Power OpAmp, Comparator and Voltage Reference in a Single Package

• Optimized for Single Supply Operation

• SmallPackages:8-PinMSOP,8-PinSOIC, 8-Pin PDI P

• Ultra Low Input Bias Current: Less than 100pA

• Low Quiescent Current: 12µA(Typ.)

• Rail-to-Rail Inputs and Outputs

•OperatesDowntoV

=1.8V,Min

Applications

• Power Management Circuits

• Battery Operated Equipment

• Consumer Products

Device Selection Table

Part Number Package

TC1026CEPA 8-Pin PDIP -40°C to +85°C

TC1026CEUA 8-Pin MSOP -40°C to +85°C TC1026CEOA 8-Pin SOIC -40°C to +85°C

Temperature

Range

Package Types

General Description

The TC1026 is a mixed-function device combining a general-purpose op amp, comparator and voltage reference in a single 8-pin package. This increased integration allows the user to r eplace two or three packages, which saves space, lowers supply current and increases system performance.

Both the op amp and comparatorhaverail-to-rail inputs and outputs which allows operation from low supply voltages with large input and output swings. The TC1026 is optimized for low voltage (V

=1.8V),low

supply current (12µA typ) operation. Packaged in a space-saving 8-Pin MSOP, the TC1026

consumes half the board area of an 8-Pin SOIC and is ideal for applications requiring high integration, small size and low power. It is also available i n 8-Pin SOIC and 8-Pin PDIP packages.

Functional Block Diagram

AMPOUT

AMPIN-

AMPIN+

AMP

TC1026

CMP

CMPOUT

REF (CMPIN-)

8-Pin PDIP

-Pin M

Voltage

Reference

CMPIN+

-Pin SOI

AMPOUT

AMPIN

AMPIN+

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2002 Microchip TechnologyInc. DS21725B-page 1

TC1026CEP TC1026CE TC1026CE

CMPOUT

REF (CMPIN)

CMPIN+

TC1026

1.0 ELECTRICAL CHARACTERISTICS

*Stresses above 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 above those indicated in the

ABSOLUTE MAXIMUM RATINGS*

Supply Voltage......................................................6.0V

operation sections of the specifications is not implied. Exposure to Absolute Maximum Rating conditions for extended periods may affectdevice reliability.

Package Power Dissipation:

8-Pin PDIP ...............................................730 mW

8-Pin SOIC...............................................470 mW

8-Pin MSOP .............................................320 mW

Voltage on Any Pin..........(V

– 0.3V) to (VDD+0.3V)

Junction Temperature.......................................+150°C

Operating Temperature Range.............-40°C to +85°C

StorageTemperature Range..............-55°C to +150°C

TC1026 ELECTRICAL SPECIFICATIONS

Electrical Characteristics: Typical values apply at 25°C and VDD=3.0V;TA= -40° to +85°C, and VDD= 1.8V to 5.5V,unless

otherwise specified.

Symbol Parameter Min Typ Max Units Test Conditions

Op Amp

VOL

ICMR

OS (DRIF T)

GBWP Gain-Bandwidth Product — 90 — kHz V

SR Slew Rate — 35 — mV/µsec CL= 100pF

OUT

CMRR Common Mode Rejection Ratio 66 — — dB T

PSRR Power Supply Rejection Ratio 80 — — dB TA=25°C,VCM=V

SRC

SINK

En Input Noise Voltage — 10 — µVpp 0.1Hz to 10Hz en Input Noise Voltage Density — 125 — nV/√Hz

Comparator

Supply Voltage 1.8 — 5.5 V Supply Current — 12 18 µA All outputs unloaded

LargeSignal Voltage Gain — 100 — V/mV RL=10kΩ, VDD=5V CommonModeInputRange VSS–0.2 — VDD+0.2 V Input Offset Voltage ±100

±0.3

±500 ±1.5

µVmVVDD=3V,VCM=1.5V,TA=25°C

= -40°C to 85°C

Input Bias Current -100 50 100 pA TA=25°C,VCM=VDDto V Input Offset Voltage Drift — ±4 — µV/°C VDD=3V,VCM=1.5V

= 1.8V to 5.5V;

O=VDD

Gain = 1 V

IN=VSS

to V

=1MΩ to GND

to V

Output Signal Swing VSS+0.05 — VDD–0.05 V RL=10kΩ

=25°C,VDD=5V

CM=VDD

VDD=1.8Vto5V

Output Source Current 3 — — mA VIN+=VDD,VIN-=V

OutputShorted to V VDD=1.8V,Gain=1

OutputSInkCurrent — 125 — nV/Hz IN+ = VSS,IN-=V

OutputShorted to V VDD=1.8V,Gain=1

to V

1kHz

Input Voltage Range VSS–0.2 — VDD+0.2 V Input Offset Voltage -5

-5

— —

+5 +5

mV VDD=3V,TA=25°C

= -40°C to 85°C

Input Bias Current –– — ±100 pA TA=25°C,IN+=VDDto V OutputHighVoltage VDD–0.3 — — V RL=10kΩ to V OutputLowVoltage — — 0.3 V RL=10kΩ to V

SS DD

DS21725B-page 2

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2002 Microchip TechnologyInc.

TC1026

TC1026 ELECTRICAL SPECIFICATIONS (C ONTINUED)

Electrical Characteristics: Typical values apply at 25°C and VDD=3.0V;TA= -40° to +85°C, and VDD= 1.8V to 5.5V,unless

otherwise specified.

Symbol Parameter Min Typ Max Units Test Conditions

PSRR Power Supply Rejection Ratio 60 — — dB T

SRC

SINK

PD1

PD2

Output Source Current 1 — — mA IN+ = V

OutputSink Current 2 — — mA IN+ = V

Response Time — 4 — µsec 100mV Overdrive, CL= 100pF Response Time — 6 — µsec 10mV Overdrive, CL= 100pF

Voltage Reference

REF

REF(SOURCE)

REF(SINK)

L(REF)

Reference Voltage 1.176 1.200 1.221 V Source Current 50 — — µA Sink Current 50 — — µA Load Capacitance — — 100 pF

=25°C

=1.8Vto5V

OutputShortedtoV VDD=1.8V

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2002 Microchip TechnologyInc. DS21725B-page 3

TC1026

2.0 PIN DESCRIPTION

The description of t he pins are listed in Table 2-1.

TABLE 2-1: PIN FUNCTION TABLE

Pin No.

(8-Pin PDIP)

(8-Pin MSOP)

(8-Pin SOIC)

1 AMPOUT Op amp output. 2 AMPIN- Inverting op amp input. 3 AMPIN+ Non-inverting op amp input. 4V 5 CMPIN+ Non-inverting comparator input. 6 REF(CMPIN) Invertingcomparator input and voltage reference output voltage. 7 CMPOUT Comparator output. 8V

Symbol Description

Negative power supply.

Positive power supply.

DS21725B-page 4

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2002 Microchip TechnologyInc.

TC1026

3.0 DETAILED DESCRIPTION

The TC1026 i s one of a series of very low power,linear building block products targeted at low voltage, single supply applications. The TC1026 minimum operating voltageis 1.8V, and typicalsupplycurrentis only 12µA. It combines a comparator, an op amp and a voltage reference in a single package.

3.1 Comparator

The TC1026 contains one comparator. The comparator’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 beingdriven.Theinvertinginputisinternallyconnected to the output of the reference.

The c omparator exhibitspropagation delay and supply current which are largely independent of supply voltage. The low i nput bias current and offset voltage make it suitable for high impedance precision applications.

3.2 Operational Amplifier

The TC1026 contains one rail-to-rail op amp. The amplifier’s i nput 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.Thelowinput bias current and offsetvoltageof the TC1026 make it suitable for precisionapplications.

3.3 Voltage Reference

A 2.0% tolerance, internally biased, 1.20V bandgap voltage reference is included i n the TC1026. It has a push-pull output capable of sourcing and sinking at least 50µA.

4.0 TYPICAL APPLICATIONS

The TC1026 lends itself to a wide variety of applications,particularlyin battery powered systems. It typically finds application in power management, processor supervisory and interface circuitry.

4.1 External Hysteresis (Comparator)

Hysteresis can be set externally with three resistors using positive f eedback techniques (see Figure 4-1). The design procedure for setting external comparator hysteresisis as follows:

1. 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

where VRis a stable reference voltage.

at the comparator’s trip point is VR/

2. Determinethehysteresis voltage (V the upper and lower thresholds.

3. Calculate R

as follows:

EQUATION 4-1:



-----------



RAR

4. Choose the rising threshold voltage for V (V

THR

5. Calculate R

as follows:

EQUATION 4-2:

THR



–

-------



-----------------------------------------------------------=



---------------------



VRRA×

6. Verify the t hreshold voltages with these formulas:

rising:

SRC

.Sincethe

canbesetto

–

------R

)between

SRC

EQUATION 4-3:

SRC

THR

falling:

VR()RA()

 

------R



-------

++=





-------



EQUATION 4-4:

RAVDD×



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2002 Microchip TechnologyInc. DS21725B-page 5

THF

THR

--------- ------------- ---

–=



TC1026

FIGURE 4-1: CO MPARATOR

EXTERNAL HYSTERESIS CONFIGURATION

SRC

TC1026

–

TC1026

Comparator

OUT

4.2 Precision Battery Monitor

Figure 4-2 is a precision battery low/battery dead monitoring circuit. Typically, the battery low output warns the user that a battery dead condition i s imminent. Battery dead typically initiates a forced shutdown to prevent operation at low internal supply voltages(whichcan cause unstable system operation).

The circuit of Figure 4-2 uses two TC1026 devices and only six external resistors. AMP 1 is a simple buffer whileCMPTR1 and CMPTR2 provideprecisionvoltage detection using V R4 set the detection threshold for BATT LOW resistors R1and R3 set the detection threshold for BATT FAIL

. The component values shown assert BATT LOW (typical). Total current consumed by this circuit is typically 28µA at 3V. Resistors R5 and R6 provide hysteresis for comparators CMPTR1 and CMPTR2, respectively.

as a reference. Resistors R2 and

while

at 2.2V (typical) and BATT FAIL at 2.0V

4.3 Voice Band Receive Filter

The majority of spectral energy for human voices is in a 2.7kHz frequency band from 300Hz to 3kHz. To properly recover a voice signal in applications such as radios, c ellular phones and voice pagers, a low-power bandpass filter that is matched to the human voice spectrum can be implemented using Microchip’s CMOS op amps. Figure 4-3 shows a unity-gain multipole Butterworth filter with ripple less than 0.15dB in thehumanvoiceband.Thelower3dBcut-off frequency is 70Hz (single-orderresponse),whilethe upper cut-off frequency is 3.5kHz (fourth-order response).

4.4 Supervisory Audio Tone (SAT) Filter for Cellular

Supervisory Audio Tones (SAT) provide a reliable transmission path between cellular subscriber units and base stations. The SAT tone functions much like the current/voltage used in land l ine telephone systems to indicate that a phone is off the hook. The SAT tone may be one of three frequencies: 5970, 6000 or 6030Hz. A loss of SAT implies that channel conditions are impaired, and if SAT is interrupted for more than 5 seconds, a cellular call is terminated.

Figure 4-4 shows a high Q (30) first order SAT detection bandpass filter using Microchip’s CMOS op amp architecture. This circuit nulls all frequencies except the three SAT tones of interest.

DS21725B-page 6

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2002 Microchip TechnologyInc.

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