My Inquiry
My Account
Texas Instruments LM748CN
- Part No.:
- LM748CN
- Manufacturer:
- Texas Instruments
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 8-DIP (0.300", 7.62mm)
- Datasheet:
-
LM748CN.pdf
- Description:
- IC OPAMP GP 1 CIRCUIT 8DIP
- Quantity:
- Payment:
- Shipping:
Inventory:2,951
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM748CN from National Semiconductor is a general-purpose operational amplifier with external frequency compensation, designed for stable unity-gain operation and high-frequency optimization across gains. It features ±5V to ±20V supply operation, continuous short-circuit protection, differential input voltage tolerance up to ±30V, and compatibility with logic-level comparators. It is widely used in precision analog signal conditioning and industrial comparator circuits.
For engineers reviewing the LM748CN datasheet, LM748CN pinout, LM748CN application, or LM748CN equivalent, key selection considerations include its 0°C to +70°C temperature range, 300–800 kΩ input resistance, ±30V differential input rating, ±15V maximum input voltage at ±15V supplies, and dual-in-line N08B/N08E package compatibility.
Technical Context
The LM748CN uses external compensation via a single 30 pF capacitor, enabling stability across all feedback configurations-including capacitive loads-and allowing gain-dependent bandwidth optimization. Its input stage avoids latch-up even when common-mode voltage exceeds rails, supporting robust operation in noisy or mismatched systems.
As a comparator, it supports clamped output levels compatible with DTL/TTL/RTL logic families, with differential inputs rated to ±30V and input offset voltage of 1.0–6.0 mV (typ/max). It shares the same pin configuration as the LM101, facilitating drop-in replacement in legacy designs where external compensation is retained.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | ±5V to ±20V - supports wide-rail analog systems including industrial sensors and legacy test equipment |
| Input Offset Voltage | 1.0–6.0 mV - defines DC error floor in precision amplification and zero-crossing detection |
| Differential Input Voltage | ±30V - enables direct interfacing with high-voltage transducers without external attenuation |
| Input Resistance | 300–800 kΩ - limits loading on high-impedance sources such as piezoelectric sensors |
| Large-Signal Voltage Gain | 25–160 V/mV - determines closed-loop accuracy and open-loop dynamic range in amplifier/comparator modes |
| Operating Temperature Range | 0°C to +70°C - qualified for commercial-grade embedded control and instrumentation applications |
| Output Voltage Swing | ±10V to ±14V (RL ≥ 2 kΩ) - delivers usable dynamic range near supply rails for single-supply-compatible designs |
Pinout & Package
Dual-In-Line Package (DIP), 8-pin, NS Package Number N08B/N08E - standard through-hole mounting with 0.3" body width and 0.1" pin pitch.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Inverting Input (−) | Differential input node | Accepts signal for phase inversion; supports ±30V differential swing relative to non-inverting input |
| Non-Inverting Input (+) | Differential input node | Reference input for follower or non-inverting gain stages; immune to latch-up beyond rail limits |
| Output | Amplified/comparator output | Drives TTL/DTL/RTL loads directly; clamping diodes allow logic-level output limiting |
| Positive Supply (V+) | Power rail connection | Accepts +5V to +20V; internal current limiting protects against overcurrent during fault conditions |
| Negative Supply (V−) | Power rail connection | Accepts −5V to −20V; symmetrical supply operation ensures balanced AC coupling capability |
| Offset Null 1 | External trim terminal | Connects to potentiometer wiper for manual nulling of input offset voltage |
| Offset Null 2 | External trim terminal | Completes nulling circuit; used with Offset Null 1 to adjust input stage bias imbalance |
| Compensation | External capacitor node | Connects 30 pF capacitor to ground for unity-gain stability; adjustable for higher-gain bandwidth optimization |
Key Features
| Feature | Design Value |
|---|---|
| External frequency compensation | Single 30 pF capacitor enables stable unity-gain operation and customizable bandwidth vs. gain trade-offs |
| Logic-compatible comparator mode | Clampable output allows direct interfacing with DTL, TTL, and RTL logic families without level-shifting circuitry |
| No latch-up under overvoltage | Continues normal operation even when common-mode input exceeds supply rails-critical for sensor fault tolerance |
| Continuous short-circuit protection | Internally limits output current to prevent thermal damage during sustained load faults up to +125°C case temperature |
| LM101 pin-compatible layout | Enables drop-in replacement in existing LM101-based designs without PCB revision, preserving legacy board investments |
Applications
| Industrial Sensor Signal Conditioning | Legacy Test Equipment Amplifier Stage |
|---|---|
Use Scenario: Amplifying low-level outputs from strain gauges and thermocouples in factory-floor monitoring systems. IC Role / Device Role / Timing Role: Precision DC-coupled op-amp with manual offset nulling and rail-to-rail input tolerance. Use Value: 1.0–6.0 mV input offset and ±30V differential input enable accurate measurement without front-end attenuation or isolation. | Use Scenario: Replacing aging op-amps in calibrated oscilloscope vertical amplifiers and function generator output stages. IC Role / Device Role / Timing Role: General-purpose amplifier with external compensation for predictable bandwidth control and stability margin tuning. Use Value: External 30 pF compensation allows precise bandwidth adjustment per channel, matching vintage instrument calibration requirements. |
| TTL-Compatible Voltage Comparator | High-Voltage Differential Threshold Detector |
Use Scenario: Converting analog sensor thresholds into clean digital signals for microcontroller interrupt inputs in PLC I/O modules. IC Role / Device Role / Timing Role: Comparator with clamped output and ±30V input tolerance, driving TTL logic directly. Use Value: Eliminates need for external level shifters or Schmitt triggers-reduces BOM count and improves noise immunity in industrial control. | Use Scenario: Detecting overvoltage events across 24V–48V DC power rails in telecom power supplies and battery management systems. IC Role / Device Role / Timing Role: High-common-mode comparator using differential inputs referenced to system ground. Use Value: ±30V differential input rating allows direct sensing of rail-to-rail voltage differences without resistive dividers or isolation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar operational amplifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM301AN | Same pinout, internal compensation, lower input resistance (2 MΩ min), no offset null pins | Lacks manual offset trimming; less suitable for precision DC-coupled amplifiers requiring <2 mV offset | Select LM301AN only when simplicity and internal compensation outweigh offset nulling needs |
| LM741CN | Same pinout, internal compensation, higher input bias current (80 nA typ), no differential input rating >±15V | Not rated for ±30V differential inputs; unsuitable for high-voltage comparator use cases | Choose LM741CN for cost-sensitive, non-critical amplification where ±15V differential input suffices |
Compared with LM301AN and LM741CN, the LM748CN uniquely provides both external compensation flexibility and ±30V differential input capability-making it the only option among the three for high-voltage comparator applications with tunable bandwidth and precision offset control.
Availability
LM748CN is available at Aetrix Electronics and suitable for industrial sensor signal conditioning, legacy test equipment repair, TTL-compatible voltage comparison, and high-voltage differential threshold detection requiring stable component supply and long-term obsolescence mitigation.
Supply support for LM748CN includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
National Semiconductor was a U.S.-based semiconductor company specializing in analog and mixed-signal ICs, acquired by Texas Instruments in 2011. Its legacy op-amp portfolio remains widely deployed in industrial and instrumentation systems.
The LM748CN belongs to National's general-purpose op-amp family designed for reliability, ease of compensation, and interoperability with older bipolar amplifier standards-targeting repair, calibration, and analog signal integrity in commercial-grade environments.
FAQ
What is the maximum supply voltage for the LM748CN?
The LM748CN supports a maximum supply voltage of ±22V, as specified in its Absolute Maximum Ratings. Operation beyond this limit risks permanent device damage. For reliable long-term use, National Semiconductor recommends staying within ±20V, especially at elevated ambient temperatures where thermal derating applies per Note 1 in the datasheet. The LM748CN maintains full electrical specifications across ±5V to ±20V.
Does the LM748CN have internal frequency compensation?
No, the LM748CN requires external frequency compensation using a single 30 pF capacitor connected between the Compensation pin and ground. This design allows users to optimize bandwidth versus gain and ensures stability with capacitive loads. Unlike internally compensated op-amps such as the LM741CN, the LM748CN gives designers full control over compensation network selection and placement.
Can the LM748CN be used as a comparator?
Yes, the LM748CN can operate as a comparator with differential inputs up to ±30V and clamped output levels compatible with DTL, TTL, and RTL logic families. Its lack of internal hysteresis means external positive feedback may be added for noise immunity. The output clamping feature-enabled via external diodes-ensures safe logic-level interfacing without additional level-shifting components.
What is the input offset voltage specification for the LM748CN?
The LM748CN has an input offset voltage of 1.0 mV (minimum), 5.0 mV (typical), and 6.0 mV (maximum) at TA = 25°C with RS ≤ 10 kΩ. Over the full 0°C to +70°C operating range, the maximum offset increases to 6.0 mV. Manual nulling is supported via dedicated Offset Null pins, enabling sub-millivolt residual offset in precision applications when properly trimmed.
Is the LM748CN pin-compatible with other National Semiconductor op-amps?
Yes, the LM748CN uses the same 8-pin DIP pinout as the LM101, allowing direct physical replacement in legacy designs. However, unlike the LM101, the LM748CN includes dedicated Offset Null and Compensation pins-requiring verification that the host PCB provides appropriate connections. No changes are needed for basic amplifier use, but optimal performance requires implementing the external 30 pF compensation capacitor.
LM748CN Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Amplifier Type:
- General Purpose
- Number of Circuits:
- 1
- Output Type:
- -
- Slew Rate:
- 0.5V/µs
- Gain Bandwidth Product:
- 1 MHz
- -3db Bandwidth:
- -
- Current - Input Bias:
- 120 nA
- Voltage - Input Offset:
- 1 mV
- Current - Supply:
- 1.8mA
- Current - Output / Channel:
- -
- Voltage - Supply Span (Min):
- 10 V
- Voltage - Supply Span (Max):
- 40 V
- Operating Temperature:
- 0°C ~ 70°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 8-DIP
LM748CN FAQ
1.How can I place an order for LM748CN through Aetrix?
Please submit a Request for Quotation (RFQ) for LM748CN on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LM748CN reliable?
The price and inventory of LM748CN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM748CN is usually 5 days.
3.What payment methods are accepted for LM748CN?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM748CN transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM748CN?
LM748CN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM748CN order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LM748CN?
For technical support, including LM748CN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM748CN requirements.
6.How does Aetrix verify that LM748CN is sourced from the original manufacturer or authorized distributors?
All LM748CN products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LM748CN meets industry standards.
7.What is the process for return or replacement of LM748CN?
All LM748CN units undergo pre-shipment inspection (PSI). If there is an issue with LM748CN, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LM748CN part is unused and in its original packaging.
Return procedure for LM748CN:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM748CN Tags
-
LM358DT
STMicroelectronics
-
LM358DR
Texas Instruments
-
LM2904DR
Texas Instruments
-
LM358ADR
Texas Instruments
-
LM2904DGKR
Texas Instruments
-
LM324DR
Texas Instruments
-
MCP6006T-E/OT
Microchip Technology
-
MCP6006UT-E/OT
Microchip Technology
-
LM324PWR
Texas Instruments
-
LM2902PWR
Texas Instruments
-
LM2902DR
Texas Instruments
-
LM358P
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
