LT1970IFE - ±500mA Power Op Amp | Analog Devices
料号： LT1970IFE ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $8.32 | $8.32 |
| 10 | $7.65 | $76.50 |
| 100 | $6.85 | $685.00 |
| 500 | $6.2 | $3,100.00 |
| 1,000 | $5.55 | $5,550.00 |
LT1970IFE 概述
A power op amp is a specialized operational amplifier designed to deliver output power levels orders of magnitude greater than a conventional op amp. Unlike a small-signal op amp that typically sources or sinks tens of milliamps, a power op amp integrates output stages capable of hundreds of milliamps to several amps, often with thermal protection, current limiting, and short-circuit handling. Power op amps sit hierarchically between op amps and power management ICs, frequently replacing discrete driver + MOSFET combinations in programmable current sources, motor drivers, and audio line drivers. The LT1970 specifically combines power-output stages with adjustable precision current limiting, making it a single-chip alternative to discrete driver designs.
Key features include ±500 mA minimum output current, 2 % accurate independent source and sink current-limit programming via external control voltages, the ability to boost output current by adding external power transistors, single or split supply operation from 5 V to 36 V, and thermal shutdown with the exposed pad for low thermal resistance. The output stage swings to within ±2.5 V of either supply rail at full current.
The architecture uses a precision input stage followed by a high-current output stage with separate current-sense paths. The sourcing and sinking current limits are independently programmed by two DC control voltages on the ILIM+ and ILIM- pins, allowing asymmetric profiles for charging supercapacitors or driving inductive loads. External boost transistors can multiply output current beyond 500 mA while preserving the precision current-limit function.
Typical applications include programmable current sources for LED drivers, solenoid and actuator drivers, motor torque drivers, headphone amplifiers, programmable power supplies, and battery chargers. The wide supply range makes the LT1970 particularly suited to industrial 24 V bus systems and automotive 12 V/24 V loads.
When designing with this device, place a 1 µF bypass capacitor close to each supply pin and use the exposed pad for thermal dissipation. For applications above 500 mA, ensure the external boost transistors are mounted on a thermally adequate footprint and that the current-limit control voltages remain stable across the operating temperature range.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes for the LT1970IFE that complement the official datasheet by adding cross-source comparisons and PCB-level guidance.
直接替换替代料： LT1970IFE ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： LT1970IFE （相同外形与封装尺寸） ——差异在于 Lead-Free / RoHS, Package.
快速对比工具——选择替代料号进行并排对比：
LT1970IFE#PBF
✅ 直接替换📋 参考替代料（不在目录中）
LT1970AIFE#PBF
✅ 直接替换📋 参考替代料（不在目录中）
LT1970CFE#PBF
✅ 直接替换📋 参考替代料（不在目录中）
LT1970HFE
✅ 直接替换📋 参考替代料（不在目录中）
LT1970IFE 最大额定值与电气特性
| Product Type | Power Operational Amplifier |
| Output Current | ±500 mA minimum |
| Number of Channels | 1 |
| Supply Voltage (Total) | 5 V to 36 V |
| Supply Type | Single or Split |
| Current Limit Accuracy | 2 % (typical) |
| Current Limit Programming | Separate ILIM+ and ILIM- control voltages |
| Output Swing | Within ±2.5 V of either supply rail at full load |
| External Current Boost | Supported via external power transistors |
| 工作温度范围 | -40 °C to +85 °C (I grade) |
| 封装 | 20-pin TSSOP-EP (Exposed Pad) |
| 安装类型 | Surface Mount |
| 热关断 | Yes |
| Lead-Free / RoHS | Lead-free (PBF suffix); RoHS-compliant variants available |
| Datasheet Document | 1970fe.pdf (per Analog Devices product page) |
LT1970IFE 引脚配置
| 引脚 1 | NC — No connection (per datasheet) |
| 引脚 2 | NC — No connection (per datasheet) |
| 引脚 3 | IN+ — Non-inverting input |
| 引脚 4 | IN- — Inverting input |
| 引脚 5 | VREF — Reference voltage for current-limit programming |
| 引脚 6 | ILIM+ — Source current-limit control voltage |
| 引脚 7 | ILIM- — Sink current-limit control voltage |
| 引脚 8 | V- — Negative supply |
| 引脚 9 | V- — Negative supply |
| 引脚 10 | NC — No connection (per datasheet) |
| 引脚 11 | NC — No connection (per datasheet) |
| 引脚 12 | OUT — Power output |
| 引脚 13 | V+ — Positive supply |
| 引脚 14 | V+ — Positive supply |
| 引脚 15 | NC — No connection (per datasheet) |
| 引脚 16 | NC — No connection (per datasheet) |
| 引脚 17 | NC — No connection (per datasheet) |
| 引脚 18 | NC — No connection (per datasheet) |
| 引脚 19 | NC — No connection (per datasheet) |
| 引脚 20 | NC — No connection (per datasheet) |
| 引脚 EP | Exposed Pad — Thermal pad, solder to PCB ground plane |
典型应用
LT1970IFE 适用于 7 应用s: Programmable Current Source / Sink, Solenoid and Actuator Driver, Headphone / Line Driver Amplifier, Battery Charger Current Controller, DC Motor Torque / Voice-Coil Driver, Programmable Power Supply Output Stage, LED Driver with Thermal Foldback.
Programmable Current Source / Sink
The LT1970IFE's independently programmable sourcing and sinking current limits (set by DC voltages on ILIM+ and ILIM- with 2 % accuracy) make it ideal for precision current-source applications such as battery formation, supercapacitor test, and LED string drivers. It replaces discrete op amp + MOSFET + sense resistor designs with a single 20-pin TSSOP-EP chip. Output current up to ±500 mA is available without external boost transistors; the part handles both charge and discharge profiles independently, supporting asymmetric profiles required by battery-conditioning and active-cell-balancing systems.
推荐
Solenoid and Actuator Driver
With ±500 mA output swing and 5 V to 36 V supply operation, the LT1970IFE drives proportional solenoids, valves, and small DC actuators directly in industrial-control loops. Its adjustable current-limit feature protects the actuator coil from overcurrent faults, while the exposed thermal pad dissipates the loss in the same IC - eliminating the need for a separate current-limit circuit. The independent source/sink limits allow controlled flyback-energy recirculation into the actuator, useful for proportional-valve and haptic-feedback applications.
推荐
Headphone / Line Driver Amplifier
The LT1970IFE is widely used as a headphone amplifier driver because its ±500 mA output current swings low-impedance (32 ohm to 600 ohm) headphones to full output without additional buffer stages. The 5 V to 36 V single-supply operation suits portable and line-level audio designs. Its exposed thermal pad maintains junction temperature under continuous sine-wave drive, and the precision current-limit prevents damage from accidental output shorts - a common failure mode in consumer audio products.
推荐
Battery Charger Current Controller
In lithium-ion and lead-acid battery chargers, the LT1970IFE regulates charge and discharge currents by monitoring current-sense voltages on its ILIM+ and ILIM- pins with 2 % accuracy. The independent source/sink control allows the charger to switch smoothly between CC and CV modes, while the 5 V to 36 V supply matches 1S to 8S battery packs. The exposed pad dissipates the difference between input and battery voltage times charge current, simplifying thermal design for wall-plug chargers and solar MPPT regulators.
推荐
DC Motor Torque / Voice-Coil Driver
The LT1970IFE delivers bidirectional current to small DC motors, voice coils, and voice-coil actuators in hard-disk drives, optical image-stabilization systems, and haptic-feedback modules. Its split-supply operation allows direct drive of H-bridge-like single-ended loads with controlled acceleration and deceleration profiles via the ILIM inputs. The ±500 mA continuous output drives voice coils rated up to several watts, and the exposed pad keeps the die cool during PWM-like transitions.
推荐
Programmable Power Supply Output Stage
Used as the series-pass element in a programmable lab power supply, the LT1970IFE handles ±500 mA continuously and can be paralleled with external boost transistors for higher-current rails. The ILIM+ pin sets the constant-current threshold, while the ILIM- pin sets the constant-current sink limit for two-quadrant operation - useful for testing battery-powered DUTs. The 5 V to 36 V compliance matches most lab-bench applications without an additional pre-regulator.
推荐
LED Driver with Thermal Foldback
The LT1970IFE drives high-brightness LED strings up to ±500 mA with adjustable current-limit thresholds via ILIM+ - ideal for architectural lighting, automotive LED modules, and industrial machine-vision illumination. The exposed pad maintains thermal performance at high currents, and the 5 V to 36 V supply accommodates both 12 V and 24 V bus systems. Programming the source limit with a temperature-dependent voltage (from an NTC + resistor divider) enables automatic thermal foldback without firmware intervention.
推荐
推荐产品汇总
工程参考数据： LT1970IFE ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | LT1970IFE#PBF | LT1970AIFE#PBF | LT1970CFE#PBF | LT1970HFE |
|---|---|---|---|---|---|
| Brand | Analog Devices (formerly Linear Technology) | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 20-pin TSSOP-EP | 20-pin TSSOP-EP - same | 20-pin TSSOP-EP - same | 20-pin TSSOP-EP - same | 20-pin TSSOP-EP - same |
| Output Current | ±500 mA | ±500 mA | ±500 mA | ±500 mA | ±500 mA |
| Supply Voltage | 5 V to 36 V | 5 V to 36 V | 5 V to 36 V | 5 V to 36 V | 5 V to 36 V |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +125 °C (extended) | 0 °C to +70 °C | -40 °C to +125 °C (military) |
| Lead-Free / RoHS | Verify per suffix | Yes (lead-free) | Yes (lead-free) | Yes (lead-free) | Verify per suffix |
| Current-Limit Accuracy | 2 % (typical) | 2 % | 2 % (tighter grade) | 2 % | 2 % |
| Datasheet Document | 1970fe.pdf | 1970fe.pdf (same) | 1970fe.pdf (same) | 1970fe.pdf (same) | 1970fe.pdf (same) |
关键差异点
- Programmable bidirectional current limit without external sense resistor （对比 LT1970IFE#PBF)
- External boost transistors multiply output beyond 500 mA （对比 Discrete op amp + MOSFET designs)
- Wide supply range with single or split operation （对比 LT1970CFE#PBF)
设计说明
The LT1970IFE's TSSOP-EP package relies on the exposed pad for thermal dissipation. Solder the EP directly to a PCB ground plane with thermal vias for heat transfer; without proper EP soldering the device will overheat at sustained ±500 mA loads. Estimated: at VIN=24 V, VOUT=12 V, IOUT=500 mA, dissipation = (24-12)*0.5 = 6 W, which requires the EP to be mounted on at least 1 square inch of 2 oz copper to keep junction rise within the 85 °C industrial limit.
Place a 1 µF low-ESR ceramic bypass capacitor as close as possible to each V+ and V- supply pin, and add a 10 µF bulk capacitor on each rail at the board entry point. The ILIM+ and ILIM- reference voltages should be filtered with 0.1 µF capacitors to prevent noise-induced current-limit jitter; this is critical when programming sub-100 mA limits. Do not exceed the absolute maximum differential supply of 36 V.
A common mistake is leaving ILIM+ or ILIM- floating - if either pin is left open, the internal default may allow full ±500 mA without limit protection. Always tie ILIM+ and ILIM- to defined reference voltages through low-impedance dividers. Also, do not use the output (pin 12) as a current-sense point - the LT1970 samples current internally; external sense resistors are not required and will degrade accuracy.
Keep the input traces (IN+, IN-) short and shielded with a ground guard trace to prevent noise pickup, especially at high source/sink currents. Place the feedback resistors directly at the IN- pin with the inverting input trace running over a continuous ground plane. The exposed pad must be electrically tied to the system ground (V-) to provide the return path for the high-current output stage.
合规信息
LT1970IFE#PBF variant is lead-free and RoHS-compliant per Analog Devices ordering information. Halogen-free status not explicitly stated in the verified web data. AEC-Q100 not applicable for this op amp family.
