The LP239, LP339, LP2901 are low-power quadruple differential comparators. Each device consists of four
independent voltage comparators designed specifically to operate from a single power supply and typically to
draw 60-µA drain current over a wide range of voltages. Operation from split power supplies is also possible
and the ultralow power supply drain current is independent of the power supply voltage.
Applications include limit comparators, simple analog-to-digital converters, pulse generators, squarewave
generators, time delay generators, voltage controlled oscillators, multivibrators, and high-voltage logic gates.
The LP239, LP339, LP2901 were specifically designed to interface with the CMOS logic family. The ultralow
power supply current makes these products desirable in battery-powered applications.
The LP239 is characterized for operation from – 25°C to 85°C. The LP339 is characterized for operation from
0°C to 70°C. The LP2901 is characterized for operation from – 40°C to 85°C.
AVAILABLE OPTIONS
PACKAGE
T
A
0 °C to 70 °C±5 mVLP339DLP339NLP339J
– 25 °C to 85 °C±5 mVLP239DLP239NLP239J
– 40 °C to 85 °C±5 mVLP2901DLP2901NLP2901J
The D package is available taped-and-reeled. Add R suffix to device type when ordering (e.g., LP339DR).
VIOmax AT 25°C
SMALL OUTLINEPLASTIC DIPCERAMIC DIP
(D)(N)(J)
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Lead temperature range 1,6 mm (1/16 inch) from case for 10 seconds: D or N package 260°C. . . . . . . . . . .
Lead temperature range 1,6 mm (1/16 inch) from case for 60 seconds: J package 300°C. . . . . . . . . . . . . . . .
†
Stresses beyond 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 beyond those indicated in the recommended operating conditions is not implied.
Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. All voltage values, except differential voltages, are with respect to the network ground.
2. Differential voltages are at IN+ with respect to IN –.
3. This input current only exists when the voltage at any of the inputs is driven negative. The current flows through the collector-base
junction of the input clamping device. In addition to the clamping device action, there is lateral n-p-n parasitic transistor action. This
action is not destructive and normal output states are re-established when the input voltage returns to a value more positive than
– 0.3 V at TA = 25°C.
4. Short circuits between outputs to VCC can cause excessive heating and eventual destruction.
5. If the output transistors are allowed to saturate, the low bias dissipation and the on-off characteristics of the outputs keep the
dissipation very small (usually less than 100 mW).
Full range is –25°C to 85°C for the LP239, 0°C to 70°C for the LP339, and –40°C to 85°C for the LP2901.
NOTES: 6. VIO is measured over the full common-mode input voltage range.
7. Because of the p-n-p input stage, the direction of the current is out of the device. This current is essentially constant (i.e., independent
of the output state). No loading change exists on the reference or input lines as long as the common-mode input voltage range is
not exceeded.
8. The output sink current is a function of the output voltage. These devices have a bimodal output section that allows them to sink
(via a Darlington connection) large currents at output voltages greater than 1.5 V, and smaller currents at output voltages
less than 1.5 V.
Figure 1 shows the basic configuration for using the LP239, LP339, or LP2901 comparator. Figure 2 shows the
diagram for using one of these comparators as a CMOS driver.
V
CC
30 kΩ
IN +
IN –
+
–
1/4 LP239, LP339,
or LP2901
Figure 1. Basic Comparator
OUT
IN +
IN –
1/4 LP239, LP339,
or LP2901
3
+
–
12
100 kΩ
1/4 SN54/74ALS1000A
V
CC
1/4 SN54/74LS00 or
OUT
Figure 2. CMOS Driver
All pins of any unused comparators should be grounded. The bias network of the LP239, LP339, and LP2901
establishes a drain current that is independent of the magnitude of the power supply voltage over the range of
2 V to 30 V. It is usually necessary to use a bypass capacitor across the power supply line.
The differential input voltage may be larger than V
without damaging the device. Protection should be
CC
provided to prevent the input voltages from going negative by more than – 0.3 V. The output section has two
distinct modes of operation: a Darlington mode and a ground-emitter mode. This unique drive circuit permits
the device to sink 30 mA at V
= 2 V in the Darlington mode and 700 µA at VO = 0.4 V in the ground-emitter
O
mode. Figure 3 is a simplified schematic diagram of the output section. The output section is configured in a
Darlington connection (ignoring Q3). If the output voltage is held high enough (above 1 V), Q1 is not saturated
and the output current is limited only by the product of the h
of Q1, the hFE of Q2, and I1 and the 60-Ω saturation
FE
resistance of Q2. The devices are capable of driving LEDs, relays, etc. in this mode while maintaining an ultralow
power supply current of 60 µA typically.
V
CC
I1 = 6 µA
Q3
V
O
Q1
Q2
Figure 3. Output-Section Schematic Diagram
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
LP239, LP339, LP2901
LOW-POWER QUAD DIFFERENTIAL COMPARATORS
SLCS004A – OCTOBER 1987 – REVISED MA Y 1988
APPLICATION INFORMATION
Without transistor Q3, if the output voltage were allowed to drop below 0.8 V , transistor Q1 would saturate and
the output current would drop to zero. The circuit would be unable to pull low current loads down to ground or
the negative supply , if used. Transistor Q3 has been included to bypass transistor Q1 under these conditions
and apply the current I1 directly to the base of Q2. The output sink current is now approximately I1 times the
h
of Q2 (700 µA at VO = 0.4 V). The output of the devices exhibit a bimodal characteristic with a smooth
FE
transition between modes.
In both cases, the output is an uncommitted collector. Several outputs can be tied together to provide a dot logic
function. An output pullup resistor can be connected to any available power supply voltage within the permitted
power supply range, and there is no restriction on this voltage based on the magnitude of the voltage that is
supplied to V
T exas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue
any product or service without notice, and advise customers to obtain the latest version of relevant information
to verify, before placing orders, that information being relied on is current and complete. All products are sold
subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those
pertaining to warranty, patent infringement, and limitation of liability.
TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TI deems necessary to support this warranty . Specific testing of all parameters of each device is not necessarily
performed, except those mandated by government requirements.
CERT AIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF
DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL
APPLICATIONS”). TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, AUTHORIZED, OR
WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT DEVICES OR SYSTEMS OR OTHER
CRITICAL APPLICA TIONS. INCLUSION OF TI PRODUCTS IN SUCH APPLICATIONS IS UNDERST OOD TO
BE FULLY AT THE CUSTOMER’S RISK.
In order to minimize risks associated with the customer’s applications, adequate design and operating
safeguards must be provided by the customer to minimize inherent or procedural hazards.
TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent
that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other
intellectual property right of TI covering or relating to any combination, machine, or process in which such
semiconductor products or services might be or are used. TI’s publication of information regarding any third
party’s products or services does not constitute TI’s approval, warranty or endorsement thereof.
Copyright 1998, Texas Instruments Incorporated
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