Analog Devices Inc. LT1169CS8#PBF

Overview

LT1169CS8#PBF from Analog Devices (formerly Linear Technology) is a dual low-noise JFET-input operational amplifier optimized for high-impedance transducer signal conditioning. It delivers 6 nV/√Hz voltage noise, 1 fA/√Hz current noise, 5 pA typical input bias current over full common-mode range, and 1.5 pF input capacitance - enabling ultra-low-noise amplification of photocurrents, hydrophone outputs, and piezoelectric sensor signals.

For engineers reviewing the LT1169CS8#PBF datasheet, LT1169CS8#PBF pinout, LT1169CS8#PBF application, or LT1169CS8#PBF equivalent, key selection criteria include guaranteed matching specifications for instrumentation front ends, unconditional stability with ≥1000 pF capacitive loads, ±13.8 V output swing at 10 kΩ load, and validated performance at ±5 V and ±15 V supplies across –40°C to +85°C.

Technical Context

The LT1169CS8#PBF employs matched JFET input stages with enlarged geometry to simultaneously minimize voltage and current noise while maintaining >10¹³ Ω common-mode input resistance. Its architecture eliminates phase reversal during input overdrive and supports unity-gain stable operation without external compensation.

Each amplifier is 100% tested for slew rate (4.2 V/µs), gain-bandwidth product (5.3 MHz), and voltage noise (≤8 nV/√Hz max). Matching parameters-including ∆VOS ≤3.5 mV, ∆IB⁺ ≤20 pA, and ∆CMRR ≥78 dB-are guaranteed over temperature for precision instrumentation topologies.

Key Specifications

Pinout & Package

S8 package: 8-lead plastic small-outline (SO-8, narrow 0.150"), JEDEC MS-012AC compliant, thermal resistance θJA = 190°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual JFET op amp applications.

Compared with LT1113CN8#PBF and AD822ARZ, the LT1169CS8#PBF uniquely balances ultra-low current noise (1 fA/√Hz), guaranteed matching specs, and 100% tested noise/slew rate - making it the preferred choice for high-impedance transducer interfaces where both voltage and current noise contribute significantly to total system noise.

Availability

LT1169CS8#PBF is available at Aetrix Electronics and suitable for photocurrent amplification, hydrophone signal conditioning, piezoelectric accelerometer interfacing, high-precision instrumentation front ends, and active filter design requiring stable component supply and traceable sourcing.

Supply support for LT1169CS8#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 acquired Linear Technology in 2017 and maintains its legacy of precision analog ICs for demanding signal-chain applications.

The LT1169CS8#PBF belongs to Linear's ultra-low-noise JFET op amp product line, engineered specifically for high-impedance sensor interfaces where simultaneous minimization of voltage noise, current noise, and input capacitance is essential.

FAQ

What is the maximum capacitive load the LT1169CS8#PBF can drive while remaining stable?

The LT1169CS8#PBF is unconditionally stable at unity gain with capacitive loads up to 1000 pF, as verified in the datasheet's TPC17 plot. This eliminates the need for isolation resistors in sensor-buffering applications. For loads exceeding 1000 pF, a series resistor (typically 10–100 Ω) between the output and capacitor is recommended to maintain phase margin.

Does the LT1169CS8#PBF support operation from ±5 V supplies?

Yes, the LT1169CS8#PBF is fully specified and guaranteed for operation from ±5 V supplies, including input offset voltage (0.65 mV max), input bias current (20 pA max warmed up), and gain-bandwidth product (3.3 MHz min). All matching specifications also apply under ±5 V conditions.

How does the LT1169CS8#PBF achieve low current noise while maintaining low voltage noise?

The LT1169CS8#PBF achieves 1 fA/√Hz current noise through JFET input devices with ultra-low gate leakage, and 6 nV/√Hz voltage noise via enlarged input JFET geometry that maximizes transconductance. The combination yields the lowest total noise for source impedances above 50 kΩ, as confirmed in Figure 2 of the datasheet.

Is the LT1169CS8#PBF pin-compatible with other dual op amps like the OPA2111 or AD822?

The LT1169CS8#PBF uses the industry-standard SO-8 (S8) pinout shared with OPA2111, AD822, OP215, and LT1113. However, it is not a drop-in replacement due to differences in supply current, noise profile, and internal compensation - circuit validation is required when substituting.

What is the guaranteed input resistance of the LT1169CS8#PBF over temperature?

The LT1169CS8#PBF guarantees ≥10¹³ Ω common-mode input resistance over the full operating temperature range (–40°C to +85°C), as stated in the Electrical Characteristics table. This stability across temperature ensures consistent bias current and noise performance in field-deployed instrumentation.