Features, descriptions

These devices are designed by two independent voltage composition comparators to work in a wide range of power under a wide range of power supply. As long as the current consumption is and VCC is at least

low -power current consumption independent of the power supply voltage. Output can achieve wired and interpersonal relationships.

Voltage: Each comparator 0.4 mA (typical value) is connected to other episodes of the electrode opening output

Single power or dual power supply

- Maximum rated value: 2 V to 36 V dual power operation

-The test voltage is 30 V: non -V device, because the voltage difference between the two power supply is 2 V to 36 V,

- in 32 V: V suffix device input co -mode voltage for testing.

Low input bias current: 25 na (typical)

Low input offset current: 3 na (typical) (LM139) LM193 device is characterized by

Low input Disposal voltage: 2 MV (typical) 55 ° C to 125 ° C. LM293 and LM293A devices work at temperatures at -25 ° C to 85 ° C.

The characteristics of the co -mode input voltage LM393 and LM393A equipment include work grounding from 0 ° C to 70 ° C. LM2903 Device

Low output saturation voltage

Output compatible with TTL, MOS and CMOS

For products that meet MIL-PRF-38535, unless otherwise regulations, all parameters will be Test

Absolutely maximum rated value

Beyond the free air temperature range (unless otherwise explained) (1)

(123] (123] ( 1) The stress that exceeds the absolute maximum rated value may cause permanent damage to the device. These are the functional operations of the equipment under these conditions or under any other conditions. The conditions of the device are not implicit. Long -term exposure may affect the reliability of the device under absolute maximum rated conditions.

(2) Except for differential voltage, all voltage values u200bu200bare related to the grounding of the grid.

(3) Differential voltage is in+relative to IN-.

(4) The short circuit from output to VCC may cause overheating and eventually cause damage.

The electrical characteristics of lmx93

In the specified free air temperature, VCC u003d 5 V (unless there is another instructions)

(123] (123] ( 1) The full range of LM193 (minimum or most or mostLarge) is -55 ° C to 125 ° C, LM293 is 25 ° C to 85 ° C, and LM393 is 0 ° C to 70 ° C, unless otherwise regulations, otherwise the measurement characteristics are measured under the input voltage of the zero-coefficient.

(2) The negative value of the input or co -mode voltage must not exceed 0.3V. For the inverter input ( -), the upper limit of the co -mode voltage range is VCC+ - 1.5V, and the non -inverter input (+) can exceed the VCC level; the comparator provides the correct output state. Any or two inputs can reach 30 V without damage.

The electrical characteristics of LM2903 and LM2903A

In the prescribed free air temperature, VCC u003d 5 V (unless otherwise instruction ] (1) The full range of LM2903 (minimum or maximum) is -40 ° C to 125 ° C. All characteristics are used for measurement voltage with zero -co -model input, unless there are other regulations.

(2) VCC MAX u003d 30 V (non -V (non -V -type device) and 32 V (V (V Damnial device).

(3) The negative value of the input or co -mode voltage should not exceed 0.3 V. The upper limit of the co -mode voltage range is VCC+–1.5 V, but any or two inputs can reach 30 V (for V suffix device, 32 V) without damage.

Typical features

Overview

LM2903 is a dual comparator, which can run up to 36 volts on the power pins. This standard device has proven to be ubiquitous and multifunctional in wide applications. This is due to the very wide power supply voltage range (2 to 36 volts), low IQ and rapid reaction equipment. Open leak output allows users to configure the logical low voltage (VOL) of the output output, and can be used to enable the use of comparators.

Function description

LM2903 consists of a PNP Dallington input, allowing the device Essence The input of Darlington has generated the ability to limit the voltage of the input co -mode, allowing LM2903 to work accurately from the ground to VCC -1.5V differential input. This provides a lot of space for the modern power of 3.3V and 5V. The output includes a leakage NPN (drop -down or low -voltage side) transistor. The output NPN will absorb the current when the positive input voltage is higher than the negative input voltage and offset voltage. The volume is the resistance and will shrink according to the output current. For the VOL value of the output current, see Figure 3.

Equipment function mode

Voltage comparison

LM2903 is only used as a voltage comparator, comparing the difference between positive polesThe voltage negative foot, and the polarity is poor according to the input and output low impedance or high impedance logic (with high logic high logic).

Application information

LM2903 is usually used to compare a single signal with the reference signal or two signals. Many users use the drain opening output drive to the logical output to the logical voltage level MCU or logical device. The wide power range and high voltage capacity make the LM2903 most suitable for higher or lower voltage.

Detailed design program

When using LM2903 in general comparators, determine the following:

input voltage range [123 123 ]

Minimum overvoltage

output and drive current

Response time

Input voltage range

The voltage range (VICR) must take into account the account. If the temperature operation is higher or less than 25 ° C, the range of VICR is 0 V to VCC – 2.0 V. This limit input voltage range is as high as VCC – 2.0 V, as low as 0 V. Operations beyond this range can produce incorrect comparisons. The following is a list of input voltage and its results:

1. When IN-and IN+are within the scope of the co-mode: (A) If IN-higher than IN+and bias voltage, the output is low, and the output is low, and the output is low.输出晶体管下沉现在的（b） 如果IN-低于IN+和偏置电压，则输出为高阻抗，而输出晶体管为不导电

2.当IN-高于共模且IN+在When the co-module, the output is low and the output transistor is sinking current

3. When IN+is higher than the co-mode and IN-in the co-mode, the output is high impedance and the output transistor is not turned on

4. When the IN-and IN+are higher than the co-mode, the output is very low, and the output transistor is sinking now

minimum overvoltage

over-drive voltage is a comparator positive Differential voltage excessive offset voltage (VIO) generated between negative input. In order to accurately compare the voltage of VOD (overspeed) higher than the input offset voltage (VIO). Over -drive voltage can also determine the comparator, and the response time decreases with the driver. Figure 8 and 9 show positive values u200bu200band negative response time to excessive drive voltage.

Output and drive current

The output current is determined by the load/upper pull resistor and logic/pull -up voltage. The output current will generate a low voltage (VOL) from the comparator. Among them, VOL is proportional to the output current. Use the typical feature of VOL based on the output current. The output current also affects the transient response. For details, see the response time.

Response time

Instant response can be determined by load capacitors (CL)), load/upper pull resistance (RPULLUP) and equivalent electrode transmission pole resistance (RCE).

Positive response time (τP) is about τP ~ RPULLUP × CL. The negative response time (约N) is about τN ~ RCE × CL – RCE can determine the temperature by taking the typical characteristics of the typical characteristics in its linear area, or use the volume to divide the iOUT

application curve

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[ 123] The following curves are generated under VCC and Vlogic, RPULLUP u003d 5.1 kΩ, and 50 PF oscilloscope probes.

Power recommendation

For rapid response and comparative applications with noise or AC input, TI is recommended to use capacitors on bypass power pins to be used for use for use for use for use for the capacitance pins for used for use for the capacitor pins. Inhibit any changes in the power supply voltage. This change will affect the co -mode range of the input comparator and produce inaccurate comparisons.

Layout

Layout Guide

There is no delay in accurate comparative applications. What is important is to maintain a stable power supply minimum noise and small failure, which may affect high electricity Flat -input co -mode voltage range. For this reason, it is best to add a bypass container between the power supply voltage and ground. This should be executed on the positive power supply and negative power supply (if any). If the negative power supply is used, do not place a capacitor between the GND pins of the IC and the system grounding.