Part A
AM26LV31IDR
Техасские инструменты
- Lifecycle
- Active
- Stock
- 3059 ПКС
- Package
- SOIC-16
- Series
- Интерфейс - драйверы, приемники, передатчики
Replacement verdict
Compatible functional replacement candidate
The AM26LV31IDR and AM26LS31CDE4 are both quad differential line drivers with matching pinout and function, making them viable functional substitutes in many designs. However, the AM26LV31IDR is a low-voltage (3.3 V) device while the AM26LS31CDE4 operates at 5 V, so supply voltage, output levels, and thermal margins must be validated before substitution. Designers should confirm logic-level compatibility and power-supply configuration prior to adoption.
Supply Voltage
Validation required
Driver Function
High match
Pin Configuration
High match
Output Voltage Levels
Validation required
Parts at a glance
Part B
AM26LS31CDE4
Техасские инструменты
- Lifecycle
- Active
- Stock
- 8888 ПКС
- Package
- SOIC-16
- Series
- Интерфейс - драйверы, приемники, передатчики
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AM26LV31IDR | AM26LS31CDE4 | Why it matters |
|---|---|---|---|
| Supply Voltage (Vcc) | 3.0 V to 3.6 V | 4.75 V to 5.25 V | The two devices operate on different supply rails (3.3 V vs 5 V), so they are not drop-in replacements without adjusting the power supply. |
| Logic Family | LV (Low-Voltage) differential line driver | LS (standard 5 V) differential line driver | Different logic families imply different input thresholds and output levels, affecting interoperability with surrounding logic. |
| Output Type | 3-state differential (RS-422 compatible) | 3-state differential (RS-422 compatible) | Both provide tri-state differential outputs, but the voltage swing differs due to the supply rail difference. |
| Differential Output Voltage (typical) | ~2.0 V (with 3.3 V supply) | ~2.5 V (with 5 V supply) | Output swing affects signal margin over cable length and compatibility with receivers expecting a particular differential level. |
| Propagation Delay (typical) | ~6 ns | ~10 ns | Faster propagation delay supports higher data rates and tighter timing budgets in the transmission path. |
| Operating Temperature Range | -40 °C to +85 °C | 0 °C to +70 °C | The wider industrial temperature range of the LV part allows use in harsher environments where the commercial-grade LS part may not be rated. |
| Package | SOIC-16 (16-pin) | SOIC-16 (16-pin) | Identical package and pinout allow board-level footprint compatibility, though electrical differences still prevent direct substitution. |
| Number of Drivers | 4 | 4 | Both provide four differential drivers, so channel count is equivalent for multi-line transmission needs. |
| Input Compatibility | TTL/CMOS compatible at 3.3 V | TTL compatible at 5 V | Input threshold differences mean the driving logic must match the respective supply domain to avoid marginal switching. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AM26LV31IDR | AM26LS31CDE4 |
|---|---|---|
| Supplier | - | Texas Instruments |
| Part Status | Active | Discontinued at Digi-Key |
| Type | Driver | Driver |
| Protocol | RS422, RS485 | RS422, RS485 |
| Number of Drivers/Receivers | 4/0 | 4/0 |
| Voltage - Supply | 3V ~ 3.6V | 4.75V ~ 5.25V |
| Operating Temperature | -40°C ~ 85°C | 0°C ~ 70°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the AM26LV31IDR and AM26LS31CDE4?
The AM26LV31IDR is a quad differential line driver from Texas Instruments operating from a 3.3 V supply, while the AM26LS31CDE4 is a quad differential line driver operating from a 5 V supply. Both are designed for balanced transmission over twisted-pair or parallel-wire lines and are commonly used with RS-422/RS-485-type interfaces.
What is the key supply voltage difference between the AM26LV31IDR and AM26LS31CDE4?
The AM26LV31IDR is specified for a 3.0 V to 3.6 V supply (nominal 3.3 V), whereas the AM26LS31CDE4 is specified for a 4.75 V to 5.25 V supply (nominal 5 V). This difference affects logic-level compatibility, output swing, and power dissipation in the target design.
Are the AM26LV31IDR and AM26LS31CDE4 pin-compatible?
Both devices are offered in 16-pin SOIC packages with the same quad-driver pinout (inputs, outputs, and enable pins in equivalent positions). However, pin compatibility alone does not guarantee interchangeability because supply voltage, logic thresholds, and output characteristics differ; the datasheets for each device should be consulted before substitution.
What output drive current can each device source and sink?
The AM26LV31IDR is specified with a differential output drive suitable for RS-422 balanced lines at 3.3 V, while the AM26LS31CDE4 is specified for higher output drive at 5 V. Exact source/sink current and differential output voltage specifications should be taken from the respective Texas Instruments datasheets, as they are not identical between the two parts.
Can the AM26LV31IDR directly replace the AM26LS31CDE4 in an existing 5 V design?
No. The AM26LV31IDR is a 3.3 V device and is not specified for 5 V operation. Replacing a 5 V AM26LS31CDE4 with a 3.3 V AM26LV31IDR would require verifying supply compatibility, logic input thresholds, output levels, and load conditions against the AM26LV31IDR datasheet; a direct drop-in substitution is not supported by the published specifications.
What are the operating temperature ranges for these two drivers?
The AM26LV31IDR is specified over the industrial temperature range of −40 °C to +85 °C. The AM26LS31CDE4 is specified over the commercial temperature range of 0 °C to +70 °C. Designs requiring extended temperature operation should account for this difference.
Do both devices support three-state outputs and enable control?
Yes. Both the AM26LV31IDR and AM26LS31CDE4 provide three-state outputs with enable/disable control, allowing the driver outputs to be placed in a high-impedance state for bus sharing. The specific enable logic and pin assignments should be confirmed from each device's datasheet.
Which device is better suited for low-power 3.3 V systems?
The AM26LV31IDR is the appropriate choice for 3.3 V systems because it is specified for a 3.0 V to 3.6 V supply and is designed for lower-voltage operation. The AM26LS31CDE4 is a 5 V device and is not specified for 3.3 V operation, so it should not be used in a 3.3 V-only design without level shifting and verification against its datasheet.