Datasheet LM615AIN, LM615AMJ-883 Datasheet (NSC)

December 1994

LM615 Quad Comparator and Adjustable Reference

LM615 Quad Comparator and Adjustable Reference

General Description

The comparators have an input range which extends to the
negative supply, and have open-collector outputs. Improved
over the LM139 series, the input stages of the comparators
have lateral PNP input transistors which enable low input
currents for large differential input voltages and swings

a

above V

The voltage reference is a three-terminal shunt-type band­gap, and is referred to the V

.

b

terminal. Two resistors pro-

gram the reference from 1.24V to 6.3V, with accuracy of

g

0.6% available. The reference features operation over a
shunt current range of 17 mA to 20 mA, low dynamic imped­ance, broad capacitive load range, and cathode terminal
voltage ranging from a diode-drop below V

b

to above Va.

As a member of National’s Super-BlockTMfamily, the
LM615 is a space-saving monolithic alternative to a multi­chip solution, offering a high level of integration without sac­rificing performance.

Connection Diagram

M Package

Features

COMPARATORS

Y

Low operating current 600 mA

Y

Wide supply voltage range 4V to 36V

Y

Open-collector outputs

Y

Input common-mode range Vbto (V

Y

Wide differential input voltage

a

b

REFERENCE

Y

Adjustable output voltage 1.24V to 6.3V

Y

Tight initial tolerance available

Y

Wide operating current range 17 mAto20mA

Y

Tolerant of load capacitance

g

0.6% (25§C)

Applications

Y

Adjustable threshold detector

Y

Time-delay generator

Y

Voltage window comparator

Y

Power supply monitor

Y

RGB level detector

N Package

1.8V)

g

36V

Top View

TL/H/11057– 24

Top View

TL/H/11057– 1

Ordering Information

For information about surface-mount packaging of this device, please contact the

Analog Product Marketing group at National Semiconductor Corp. headquarters.

Reference

Tolerances

g

0.6% at 25§C, LM615AMN LM615AIN 16-Pin N16A
C max Molded DIP

80 ppm/

§

b

55§CsT

LM615AMJ/883 16-Pin J16A

g

2.0% at 25§C, LM615MN LM615IN 16-Pin N16A

150 ppm/§C max Molded DIP

Super-BlockTMis a trademark of National Semiconductor Corporation.

C

1995 National Semiconductor Corporation RRD-B30M115/Printed in U. S. A.

TL/H/11057

Temperature Range

Military Industrial Package Package Number

s

a

125§C

J

b

40§CsT

s

a

85§C

J

NSC

(Note 13) Ceramic DIP

LM615IM 16-Pin Narrow M16A

Surface Mount

Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.

Voltage on Any Pin Except V

(referred to Vbpin)
(Note 2) 36V (Max)
(Note 3)

Current through Any Input Pin

and V

Pin

RO

Differential Input Voltage

Output Short-Circuit Duration (Note 4)

Storage Temperature Range

RO

b

65§CsT

b

0.3V (Min)

g

s

a

J

20 mA

g

36V

150§C

Maximum Junction Temperature 150

Thermal Resistance, Junction-to-Ambient (Note 5)

N Package 95

§

Soldering Information

N Package Soldering (10 seconds) 260

ESD Tolerance (Note 6)

g

Operating Temperature Range

LM615AI, LM615I

LM615A, LM615M

b

40§CsT

b

55§CsT

s

a

85§C

J

s

a

125§C

J

C/W

1kV

C

§

C

§

Electrical Characteristics

These specifications apply for V
GND, unless otherwise specified. Limits in standard typeface are for T

b

e

GNDe0V, V

a

e

5V, V

CM

Operating Temperature Range.

Symbol Parameter Conditions

COMPARATORS

I

S

V

V

DV

I

B

I

OS

A

t

R

I

SINK

I

L

OS

OS

DT

V

Total Supply Current VaCurrent, R

Offset Voltage over 4VsV

a

V

Range 2.0 6.0 7.0 mV max

Offset Voltage over 0VsV
V

Range V

CM

Average Offset

OS

3V

a

s

s

V

a

s

CM

a

e

30V, R

Voltage Drift

Input Bias Current

Input Offset Current 0.2 4 4 nA max

Voltage Gain R

Large Signal V
Response Time Swing, R

Output Sink Current V

Output Leakage V
Current V

e

10 kX to 36V, 500 50 50 V/mV

L

s

2V

V

OUT

e

1.4V, V

a

IN

L

e

0V, V

a

IN

e

1V, V

a

IN

e

36V 0.2 mA

OUT

e %

LOAD

36V 350 600 650 mA max

36V, R

s

(V

e

L

s

27V min

e

5.1 kX 2.0 ms

b

b

, 250 550 600 mA max

e

15 kX 1.0 3.0 5.0 mV max

L

a

b

1.8V) 1.0 3.0 5.0 mV max

15 kX 1.5 6.0 7.0 mV max

e

TTL 1.5 ms

b

IN

e

1V, 20 10 10 mA min

IN

e

IN

V

OUT

V

OUT

0V, 0.1 10 10 mA max

e

e

V

Va/2, I

OUT

e

J

e

100 mA, FEEDBACK pin shorted to

R

25§C; limits in boldface type apply over the

LM615AM LM615M

Typical LM615AI LM615I

(Note 7) Limits Limits

(Note 8) (Note 8)

15 mV/

b

5 25 35 nA max

b

830 40nA max

0.3 5 5 nA max

100 V/mV

e

1.5V 13 8 8 mA min

e

0.4V 2.8 1.0 0.8 mA min

2.4 0.5 0.5 mA min

Units

C

§

2

Electrical Characteristics

These specifications apply for V
GND, unless otherwise specified. Limits in standard typeface are for T
Operating Temperature Range. (Continued)

b

e

GNDe0V, V

a

e

5V, V

CM

e

V

OUT

J

e

e

Va/2, I

e

100 mA, FEEDBACK pin shorted to

R

25§C; limits in boldface type apply over the

LM615AM LM615M

Symbol Parameter Conditions

Typical LM615AI LM615I

(Note 7) Limits Limits

(Note 8) (Note 8)

VOLTAGE REFERENCE (Note 9)

V

R

DV

DT

DV

kH

DV

DT

DV

DI

R

R Resistance DV

DV

DV

DV

DV

I

FB

e

n

Note 1: Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the
device beyond its rated operating conditions.

Note 2: Input voltage above V

Note 3: More accurately, it is excessive current flow, with resulting excess heating, that limits the voltages on all pins. When any pin is pulled a diode drop below

b

V
and unpredictable when any parasitic diode or transistor is conducting.

Note 4: Shorting an Output to V

a

V
If the total power from all shorted outputs causes the junction temperature to exceed 150
determine junction temperature, see Note 5.

Note 5: Junction temperature may be calculated using T
packages soldered to copper-clad board with dissipation from one comparator or reference output transistor, nominal i

Note 6: Human body model, 100 pF discharge through a 1.5 kX resistor.

Note 7: Typical values in standard typeface are for T

most likely parametric norm.

Note 8: All limits are guaranteed for T

Note 9: V

1.244V).

Note 10: Average reference drift is calculated from the measurement of the reference voltage at 25

6

10
parameter is guaranteed by design and sample testing.

Note 11: Hysteresis is the change in V
hysteresis to the typical value, its junction temperature should be cycled in the following pattern, spiraling in toward 25

Note 12: Low contact resistance is required for accurate measurement.

Note 13: A military RETS electrical test specification is available on request. The LM615AMJ/883 may also be procured as a Standard Military Drawing.

Reference 1.244 1.2365 1.2191 V min
Voltage 1.2515 1.2689 V max

g

(

0.6%) (g2%)

Average Drift (Note 10)

R

with Temperature max

e

Average Drift T

R

with Time T

Hysteresis (Note 11)

R

J

VRChange V

R

with Current 0.1 1.1 1.1 mV max

R[100 mA

V

R[10 mA

(Note 12) 2.0 5.5 5.5 mV max

DV

VRChange V

R

with V

RO

VRChange V

R

a

with V

FEEDBACK V

RO

a

Change 0.1 1.3 1.3 mV max

R[V

R[Vae5V

V

R[Vae5V

b

Bias Current 29 40 55 nA max

b

V

]

R[17 mA

b

V

]

R[100 mA

R[10 mA to 0.1 mA

R[100 mAto17mA

b

e

]

V

RO

R

b

V

]

b

V

]

s

s

V

5.06V 22 35 50 nA max

FB

]

]

/9.9 mA 0.2 0.56 0.56 X max

]

/83 mA 0.6 13 13 X max

]

V

R[V

RO

R[Vae36V

R[Vae3V

40§C 400 ppm/kH

J

e

150§C 1000 ppm/kH

J

e

]

6.3V

]

]

18 80 150

3.2 mV/

0.05 1 1 mV max

1.5 5 5 mV max

2.5 5 5 mV max

2.8 10 10 mV max

0.1 1.2 1.2 mV max

0.01 1 1 mV max

0.01 1.5 1.5 mV max

Voltage Noise BWe10 Hz to 10 kHz 30 mV

a

is allowed. As long as one input pin voltage remains inside the common-mode range, the comparator will deliver the correct output.

, a parasitic NPN transistor turns ON. No latch-up will occur as long as the current through that pin remains below the Maximum Rating. Operation is undefined

b

), will cause 80 mA (typ.) to be drawn through the output transistor. This current multiplied by the applied voltage is the power dissipation in the output transistor.

is the reference output voltage, which may be set for 1.2V to 6.3V (see Application Information). VRis the VRO-to-FEEDBACK voltage (nominally

RO

DVR/V

#

R[25§C

#

]

will not cause power dissipation, so it may be continuous. However, shorting an Output to any more positive voltage (including

C, degraded reliability or destruction of the device may occur. To

§

e

a

T

PDiJA. The given thermal resistance is worst-case for packages in sockets in still air. For

J

A

e

25§C; values in boldface type apply for the full operating temperature range. These values represent the

J

ea

25§C (standard type face) or over the full operating temperature range (bold type face).

J

DTJ, where DVRis the lowest value subtracted from the highest, V

caused by a change in TJ, after the reference has been ‘‘dehysterized.’’ To dehysterize the reference; that is minimize the

RO

C and at the temperature extremes. The drift, in ppm/§C, is

§

is the value at 25§C, and DTJis the temperature range. This

]

R[25§C

is 80§C/W for the N package.

JA

C: 25§C, 85§C,b40§C, 70§C, 0§C, 25§C.

§

Units

ppm/

§

RMS

C

§

C

3

Simplified Schematic Diagrams

Reference Bias

Comparator

TL/H/11057– 2

TL/H/11057– 3

4

Typical Performance Characteristics (Reference)

e

T

25§C, FEEDBACK pin shorted to V

J

b

e

0V, unless otherwise noted.

Reference Voltage
vs Temperature

Reference Voltage
vs Current
and Temperature

Reference Voltage
vs Reference Current

Reference Voltage
Drift vs Time

Reference Voltage
vs Current
and Temperature

Reference AC
Stability Range

Accelerated Reference
Voltage Drift vs Time

Reference Voltage
vs Reference Current

FEEDBACK Current
vs FEEDBACK-to-V

b

Voltage

FEEDBACK Current
vs FEEDBACK-to-V
Voltage

b

Reference Noise
Voltage vs Frequency

Reference Small-Signal
Resistance vs Frequency

TL/H/11057– 4

5

Typical Performance Characteristics (Reference) (Continued)

e

25§C, FEEDBACK pin shorted to V

T

J

b

e

0V, unless otherwise noted.

Reference
Power-Up Time

Reference Step Response
for 100 mE10 mA
Current Step

with FEEDBACK
Voltage Step

Reference Voltage
Change with Supply
Voltage Step

Typical Performance Characteristics (Comparators)

Reference Voltage

25§C, V

a

e

T

J

b

e

5V, V

e

0V, unless otherwise noted

Reference Voltage
with 100E12 mA
Current Step

TL/H/11057– 5

Supply Current
vs Supply Voltage

Input-Bias
Current vs Common-Mode
Voltage

6

Input Current vs
Differential Input Voltage

TL/H/11057– 6

Typical Performance Characteristics (Comparators) (Continued)

Output Saturation
Voltage vs Sink Current

Small-Signal Response
Times Non-Inverting Input,
Positive Transition

Large-Signal Response
Times-Inverting Input,
Negative Transition

Small-Signal Response
TimesÐInverting Input,
Negative Transition

Small-Signal Response
TimesÐNon-Inverting Input,
Negative Transition

Large-Signal Response
TimesÐNon-Inverting Input,
Positive Transition

Small-Signal Response
TimesÐInverting Input,
Positive Transition

Large-Signal Response
TimesÐInverting Input,
Positive Transition

Large-Signal Response
TimesÐNon-Inverting Input,
Negative Transition

TL/H/11057– 8

7

Application Information

VOLTAGE REFERENCE

Reference Biasing

The voltage reference is of a shunt regulator topology that
models as a simple zener diode. With current I
the ‘‘forward’’ direction there is the familiar diode transfer
function. I
ence voltage to be developed from cathode to anode. The

flowing in the reverse direction forces the refer-

r

cathode may swing from a diode drop below V
erence voltage or to the avalanche voltage of the parallel
protection diode, nominally 7V. A 6.3V reference with V
3V is allowed.

FIGURE 1. Voltage Associated with Reference

(Current Source I

is External)

r

The reference equivalent circuit reveals how Vris held at
the constant 1.2V by feedback, and how the FEEDBACK pin
passes little current.

To generate the required reverse current, typically a resistor
is connected from a supply voltage higher than the refer­ence voltage. Varying that voltage, and so varying I
small effect with the equivalent series resistance of less
than an ohm at the higher currents. Alternatively, an active
current source, such as the LM134 series, may generate I

flowing in

r

b

to the ref-

TL/H/11057– 9

r

a

, has

Capacitors in parallel with the reference are allowed. See
the Reference AC Stability Range typical curve for capaci­tance valuesÐfrom 20 mA to 3 mA any capacitor value is
stable. With the reference’s wide stability range with resis­tive and capacitive loads, a wide range of RC filter values
will perform noise filtering.

Adjustable Reference

The FEEDBACK pin allows the reference output voltage,
V

, to vary from 1.24V to 6.3V. The reference attempts to

e

ro

hold V

at 1.24V. If Vris above 1.24V, the reference will

r

conduct current from Cathode to Anode; FEEDBACK cur­rent always remains low. If FEEDBACK is connected to An­ode, then V
BACK is held at a constant voltage above AnodeÐsay

3.76V for V
stant V
ode into FEEDBACK node. A Thevenin equivalent 3.76V is
generated from FEEDBACK to Anode with R2
Keep I greater than one thousand times larger than FEED­BACK bias current for
tary grade over the military temperature range (I

e

e

V

ro

e

ro

generates a current IeR1/Vrflowing from Cath-

r

1.24V. For higher voltages FEED-

r

5V. Connecting a resistor across the con-

e

3.76/I.

k

0.1% errorÐIt32 mA for the mili-

t

5.5 mA
for a 1% untrimmed error for an industrial temperature
range part).

.

r

TL/H/11057– 12

FIGURE 4. Thevenin Equivalent of

Reference with 5V Output

FIGURE 2. Reference Equivalent Circuit

TL/H/11057– 10

TL/H/11057– 11

FIGURE 3. 1.2V Reference

R1eVr/Ie1.24/32me39k

e

R1[(Vro/Vr)b1

R2

FIGURE 5. Resistors R1 and R2 Program

Reference Output Voltage to be 5V

8

e

]

39k[(5/1.24)b1

TL/H/11057– 13

e

]

118k

Application Information (Continued)

Understanding that V
sistors, and capacitors may be tied to the FEEDBACK pin, a
range of V

temperature coefficients may be synthesized.

r

is fixed and that voltage sources, re-

r

Connecting a resistor across V
0 TC current source, but a range of TCs may be synthe-

-to-FEEDBACK creates a

RO

sized.

FIGURE 6. Output Voltage has Negative Temperature

TL/H/11057– 14

Coefficient (TC) if R2 has Negative TC

TL/H/11057– 15

FIGURE 7. Output Voltage has Positive TC

if R1 has Negative TC

TL/H/11057– 16

FIGURE 8. Diode in Series with R1 Causes Voltage

Across R1 and R2 to be Proportional to Absolute

Temperature (PTAT)

IeVr/R1e1.24/R1

TL/H/11057– 17

FIGURE 9. Current Source is Programmed by R1

TL/H/11057– 18

FIGURE 10. Proportional-to-Absolute-Temperature

Current Source

TL/H/11057– 19

FIGURE 11. Negative-TC Current Source

Reference Hysteresis

The reference voltage depends, slightly, on the thermal his­tory of the die. Competitive micro-power products varyÐal­ways check the data sheet for any given device. Do not
assume that no specification means no hysteresis.

9

Application Information (Continued)

COMPARATORS

Any of the comparators or the reference may be biased in
any way with no effect on the other sections of the LM615,
except when a substrate diode conducts (see Electrical
Characteristics Note 3). For example, one or both inputs of
one comparator may be outside the input voltage range lim­its, the reference may be unpowered, and the other compar­ators will still operate correctly. Unused comparators should
have inverting input and output tied to V
input tied to V

a

.

Hysteresis

Any comparator may oscillate or produce a noisy output if
the applied differential input voltage is near the compara­tor’s offset voltage. This usually happens when the input
signal is moving very slowly across the comparator’s switch­ing threshold. This problem can be prevented by the addi­tion of hysteresis, or positive feedback, as shown in

12

.

FIGURE 12. RSand RFAdd Hysteresis to Comparator

The amount of hysteresis added in

R

e

Vax

V

H

&

V

S

a

(R

RS)

F

R

S

a

x

R

F

for R

n

F

A good rule of thumb is to add hysteresis of at least the
maximum specified offset voltage. More than about 50 mV
of hysteresis can substantially reduce the accuracy of the
comparator, since the offset voltage is effectively being in­creased by the hysteresis when the comparator output is
high.

R

S

Figure 12

b

, and non-inverting

Figure

TL/H/11057– 20

is

It is often a good idea to decrease the amount of hysteresis
until oscillations are observed, then use three times that
minimum hysteresis in the final circuit. Note that the amount
of hysteresis needed is greatly affected by layout. The
amount of hysteresis should be rechecked each time the
layout is changed, such as changing from a breadboard to a
P.C. board.

Input Stage

The input stage uses lateral PNP input transistors which,
unlike those of many op amps, have breakdown voltage
BV

equal to the absolute maximum supply voltage. Also,

EBO

they have no diode clamps to the positive supply nor across
the inputs. These features make the inputs look like high
impedances to input sources producing large differential
and common-mode voltages.

The guaranteed common-mode input voltage range for an
LM615 is V
This is the voltage range in which the comparisons must be

b

s

V

CM

a

s

b

(V

1.8V), over temperature.

made. If both inputs are within this range, the output will be
at the correct state. If one input is within this range, and the
other input is less than (V

a

than V

, the output will be at the correct state. If, however,
either or both inputs are driven below V
current exceeds 10 mA, the output state is not guaranteed
to be correct. If both inputs are above (V

b

a

32V), even if this is greater

b

, and either input

a

b

1.8V), the

output state is also not guaranteed to be correct.

Output Stage

The comparators have open-collector output stages which
require a pull-up resistor from each output pin to a positive
supply voltage of the output to switch properly. When the
internal output transistor is off, the output (HIGH) voltage
will be pulled up to this external positive voltage.

To ensure that the LOW output voltage is under the TTL-low
threshold, the output transistor’s load current must be less
than 0.8 mA (over temperature) when it turns on. This im­pacts the minimum value of the pull-up resistor.

10

Typical Applications

Power Supply Monitor

V

OUT1

outputs, and are LOW when the
corresponding LED is ON.

All resistors 1%
tolerance or better.

and V

are optional digital

OUT2

TL/H/11057– 21

Tracking Comparator

R1– C1 removes the low-frequency signal component,
so that through R2 –C2 the higher­frequency component is detected.

TL/H/11057– 22

4-Threshold Level Detector

TL/H/11057– 23

11

12

Physical Dimensions inches (millimeters)

Ceramic Dual-In-Line Package (J)

Order Number LM615AMJ/883

NS Package Number J16A

16-Pin Narrow Surface Mount Package (M)

Order Number LM615IM

NS Package Number M16A

13

Physical Dimensions inches (millimeters) (Continued)

16-Pin Molded Dual-In-Line Package (N)

Order Number LM615IN or LM615MN

NS Package Number N16A

LM615 Quad Comparator and Adjustable Reference

LIFE SUPPORT POLICY

NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL
SEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices or 2. A critical component is any component of a life
systems which, (a) are intended for surgical implant support device or system whose failure to perform can
into the body, or (b) support or sustain life, and whose be reasonably expected to cause the failure of the life
failure to perform, when properly used in accordance support device or system, or to affect its safety or
with instructions for use provided in the labeling, can effectiveness.
be reasonably expected to result in a significant injury
to the user.

National Semiconductor National Semiconductor National Semiconductor National Semiconductor
Corporation Europe Hong Kong Ltd. Japan Ltd.

1111 West Bardin Road Fax: (
Arlington, TX 76017 Email: [e-mail] Ocean Centre, 5 Canton Rd. Fax: [phone]
Tel: [phone] Deutsch Tel: (
Fax: [phone] English Tel: (

National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.

Fran3ais Tel: (
Italiano Tel: (

a

49) 0-180-530 85 86 13th Floor, Straight Block, Tel: [phone]

a

49) 0-180-530 85 85 Tsimshatsui, Kowloon

a

49) 0-180-532 78 32 Hong Kong

a

49) 0-180-532 93 58 Tel: [phone]

a

49) 0-180-534 16 80 Fax: [phone]