Analog Devices Inc. LT1217CN8#PBF

Overview

LT1217CN8#PBF from Analog Devices (formerly Linear Technology) is a current feedback amplifier optimized for high-speed, low-power signal conditioning in precision analog systems. It delivers 10MHz bandwidth, 500V/µs slew rate, and 280ns settling to 0.1% for 10V steps, with shutdown capability reducing supply current to 350µA. It drives 75Ω cables and 100Ω loads in video, data acquisition, and IF amplification.

For engineers reviewing the LT1217CN8#PBF datasheet, LT1217CN8#PBF pinout, LT1217CN8#PBF application, or LT1217CN8#PBF equivalent, key selection criteria include its ±5V to ±15V dual-supply operation, 1mA quiescent current, 50mA minimum output drive, 1mV input offset voltage, and industry-standard 8-lead PDIP package compatibility with legacy designs.

Technical Context

The LT1217CN8#PBF uses a complementary bipolar process to achieve low 1mA quiescent current while maintaining 500V/µs slew rate and 10MHz small-signal bandwidth. Its current feedback architecture decouples closed-loop bandwidth from gain setting-bandwidth remains stable across gains when RF is fixed at 3kΩ, enabling consistent 10MHz performance into 100Ω at AV = 2.

Pin 8 provides logic-compatible shutdown: sinking >50µA places the output in high-impedance state and reduces supply current to ≤350µA. Input stage features 100MΩ resistance and 100nA bias current, with common-mode range extending to ±12V at ±15V supplies and CMRR of 60–66dB.

Key Specifications

Pinout & Package

LT1217CN8#PBF is housed in an 8-lead plastic DIP (N8) package with 0.300-inch width, JEDEC MS-001 compliant footprint, and 100°C/W junction-to-ambient thermal resistance. Pin 1 is NULL (not connected), Pin 2 is inverting input (–IN), Pin 3 is non-inverting input (+IN), Pin 4 is negative supply (V–), Pin 5 is NULL, Pin 6 is output (OUT), Pin 7 is positive supply (V+), and Pin 8 is shutdown control (SHUTDOWN).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current feedback amplifier applications.

Compared with LT1217CN8#PBF, LT1363CN8#PBF offers higher speed at the cost of 2.5× quiescent current and no shutdown, while AD811ARZ delivers RF-grade bandwidth but consumes 16× more power and lacks power management - making LT1217CN8#PBF optimal for low-power, medium-bandwidth precision analog systems requiring flexible power control.

Availability

LT1217CN8#PBF is available at Aetrix Electronics and suitable for video amplification, precision buffering, IF signal conditioning, and 75Ω cable driving applications requiring stable component supply across industrial, test equipment, and broadcast OEM programs.

Supply support for LT1217CN8#PBF 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

Analog Devices, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision instrumentation, communications, and industrial markets.

The LT1217 belongs to Linear Technology's legacy current feedback amplifier product line, designed specifically for applications demanding high speed, low power, and robust DC precision in video, data acquisition, and communication signal paths.

FAQ

What is the maximum capacitive load the LT1217CN8#PBF can drive directly without isolation?

The LT1217CN8#PBF can drive up to 100pF directly when using RF = 3kΩ, as shown in the Maximum Capacitive Load vs Feedback Resistor curve. For larger loads (e.g., 1000pF), increasing RF to 5.1kΩ maintains stability with ≤5dB peaking. Direct driving avoids series resistor gain errors but reduces bandwidth proportionally - a 10Ω isolation resistor is preferred when DC accuracy is critical and load capacitance exceeds 100pF.

Does the LT1217CN8#PBF require external compensation components for unity-gain stability?

No, the LT1217CN8#PBF is internally compensated and stable at unity gain (AV = 1) with RF = RG = 3kΩ into 100Ω. Its current feedback architecture inherently avoids the phase-margin degradation seen in voltage-feedback op amps at low gains. Stability is maintained across all standard gain configurations (AV = 1 to 100) when RF is held constant, eliminating need for external compensation networks in typical applications.

How does shutdown operation affect the output impedance and signal integrity of the LT1217CN8#PBF?

When shutdown is activated (Pin 8 sunk >50µA), the LT1217CN8#PBF output enters a true high-impedance state with leakage current <100nA, effectively disconnecting the amplifier from the load. This prevents signal coupling or loading during power-down sequences. Output recovery time from shutdown is <1µs, and the device resumes full performance (including 500V/µs slew rate and 280ns settling) immediately upon re-enabling - critical for time-multiplexed channel architectures.

Can the LT1217CN8#PBF operate from a single +12V supply, and what are the input/output voltage limitations?

Yes, the LT1217CN8#PBF supports single-supply operation (e.g., V+ = +12V, V– = 0V). Input common-mode range extends from 0V to +10V (±12V with dual supplies), and output swing reaches +10V into 2kΩ and +8V into 200Ω. For rail-to-rail input/output performance, level-shifting or AC-coupling is required - the device is not rail-to-rail, but its wide dynamic range supports most single-supply sensor interface and DAC output buffering tasks.

What is the thermal performance of the LT1217CN8#PBF in its N8 package under continuous 50mA output current?

In the 8-lead PDIP (N8) package, the LT1217CN8#PBF has θJA = 100°C/W. At 50mA output into 100Ω with ±15V supplies, power dissipation is ~1.5W, resulting in ~150°C junction rise above ambient. With 25°C ambient, TJ ≈ 175°C - exceeding the 150°C absolute maximum. Derating is required: limit continuous output current to ≤30mA or add heatsinking. For sustained 50mA operation, forced air or thermal vias are mandatory to maintain TJ ≤ 150°C.