Part A
AD590LF
テキサス・インスツルメンツ
- Lifecycle
- Active
- Stock
- 4157 個数
- Package
- CFLATPACK-2
- Series
- 温度センサー - アナログおよびデジタル出力
Replacement verdict
Compatible functional replacement candidate
The AD590KF and AD590LF are functionally interchangeable two-terminal current-output temperature transducers sharing the same temperature coefficient, supply range, and package family, with the LF grade offering tighter calibration accuracy. The KF variant is a suitable functional replacement candidate for the LF in applications where the tighter initial tolerance of the LF grade is not mandatory, though grade-specific accuracy requirements should be validated against the target design.
Output Type
High match
Temperature Coefficient
High match
Package Type
High match
Calibration Accuracy Grade
Validation required
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD590KF | AD590LF | Why it matters |
|---|---|---|---|
| Temperature Accuracy (Calibration Error at 25°C) | ±0.5°C | ±1.0°C | Determines the initial absolute accuracy of the sensor; the K grade is twice as accurate as the L grade at room temperature, directly affecting measurement precision without calibration. |
| Grade / Accuracy Class | K grade (higher accuracy) | L grade (standard accuracy) | The grade defines the guaranteed error window over the full temperature range; substituting a lower grade may violate system accuracy budgets. |
| Maximum Nonlinearity | ±0.3°C (over rated range) | ±0.5°C (over rated range) | Nonlinearity limits accuracy across the temperature span; the K grade maintains tighter linearity, which matters for wide-range temperature sensing. |
| Operating Temperature Range (Rated Performance) | -55°C to +125°C | -55°C to +125°C | Both cover the same military-grade range, but the guaranteed accuracy specifications differ within that range, affecting usable precision at extremes. |
| Temperature Coefficient of Output Current | 1 µA/K (nominal) | 1 µA/K (nominal) | The fundamental transfer function is identical (1 µA per Kelvin), so both are functionally interchangeable in the signal chain; only accuracy class differs. |
| Supply Voltage Range | +4 V to +30 V | +4 V to +30 V | Identical supply range means both can drop into the same circuit without power rail redesign. |
| Package | TO-52 (metal can) | TO-52 (metal can) | Same package ensures mechanical and footprint compatibility for direct board replacement. |
| Output Current at 25°C | 298.2 µA (nominal) | 298.2 µA (nominal) | Identical nominal output confirms the same signal scaling, so downstream readout circuitry requires no recalibration for the transfer function. |
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Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD590LF | AD590KF |
|---|---|---|
| Part Status | Active | Active |
| Sensor Type | Analog, Local | Analog, Local |
| Sensing Temperature - Local | -55°C ~ 150°C | -55°C ~ 150°C |
| Output Type | Analog Current | Analog Current |
| Voltage - Supply | 4V ~ 30V | 4V ~ 30V |
| Accuracy - Highest(Lowest) | ±1°C | ±2.5°C |
| Test Condition | 25°C | 25°C |
| Operating Temperature | -55°C ~ 125°C | -55°C ~ 125°C |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What is the primary difference between the AD590KF and AD590LF?
The main difference is the specified accuracy grade. The AD590KF is a standard-grade current output temperature transducer with a calibration error of ±2.5°C at 25°C, while the AD590LF is a higher-precision grade with a calibration error of ±1.0°C at 25°C. Both are otherwise functionally identical two-terminal IC temperature transducers.
Are the AD590KF and AD590LF pin-compatible and interchangeable?
Yes. Both devices are offered in the same package options (e.g., TO-52 metal can and SOIC) with identical pinouts and the same two-terminal current-mode architecture. They are pin-compatible, but substitution should account for the tighter accuracy specification of the AD590LF versus the AD590KF.
What is the output characteristic of the AD590KF and AD590LF?
Both are current-output temperature transducers that produce an output current proportional to absolute temperature at a nominal sensitivity of 1 µA/K. They operate over a supply voltage range of approximately 4 V to 30 V and are specified for a temperature range of −55°C to +150°C (extended ranges vary by package).
Which grade should be selected for a precision temperature measurement design?
The AD590LF should be selected when tighter initial accuracy is required, since its calibration error at 25°C is ±1.0°C compared with ±2.5°C for the AD590KF. For applications where the wider tolerance of the AD590KF is acceptable, the standard grade is the more economical choice.
Do the AD590KF and AD590LF require external calibration?
Both devices are factory-calibrated current sources, but their specified calibration errors differ. The AD590LF offers a tighter untrimmed accuracy, reducing or eliminating the need for system-level trim in precision designs, whereas the AD590KF may require external trimming in applications demanding better than its ±2.5°C specification.
What are the operating temperature and supply voltage ranges for these devices?
Both the AD590KF and AD590LF are specified over the −55°C to +150°C temperature range (with package-dependent limits) and operate from a supply voltage of 4 V to 30 V. These parameters are common to both grades and are documented in the Analog Devices AD590 datasheet.
Can the AD590KF and AD590LF be used in remote sensing applications?
Yes. Because both are two-terminal current-output devices, the output current is insensitive to voltage drops along long cable runs, making them suitable for remote temperature sensing. The choice between the KF and LF grades depends on the accuracy budget of the remote measurement system rather than on any difference in sensing architecture.