Analog Devices Inc. LTC2433-1IMS#PBF

Overview

LTC2433-1IMS#PBF from Analog Devices (formerly Linear Technology) is a micropower 16-bit differential ΔΣ analog-to-digital converter with integrated oscillator, 0.12LSB INL, 1.45µV RMS noise independent of VREF, and simultaneous 50Hz/60Hz notch rejection - used in precision weight scales, strain-gage transducers, and direct temperature measurement systems.

For engineers reviewing the LTC2433-1IMS#PBF datasheet, LTC2433-1IMS#PBF pinout, LTC2433-1IMS#PBF application, or LTC2433-1IMS#PBF equivalent, key selection criteria include its rail-to-rail differential input/reference capability, 200µA active supply current, 4µA autosleep mode, internal oscillator eliminating external timing components, and 10-lead MSOP package compatibility with LTC2431/LTC2411.

Technical Context

The LTC2433-1IMS#PBF implements a no-latency delta-sigma architecture with decimating FIR filtering and on-chip autocalibration that performs offset and full-scale correction every conversion cycle. Its digital filter achieves ≥87dB normal-mode rejection from 49Hz to 61.2Hz when FO is grounded, or configurable notch at f_EOSC/2560 ±4% with external clock.

It supports dual serial interface modes: internal SCK output (17.5kHz, 45–55% duty cycle) or external SCK input (up to 2MHz), with 19-bit output format (3 status + 16 data bits), end-of-conversion flag on Bit 18, and sign/overrange encoding via Bits 16–15. Conversion time is fixed at 146.7ms with internal oscillator.

Key Specifications

Pinout & Package

Package: 10-lead MSOP (3mm × 3mm, 0.5mm pitch), moisture sensitivity level 1, RoHS-compliant, rated for –40°C to +85°C (I-grade).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit differential ΔΣ ADC applications.

Compared with ADS124S08IPWR and LTC2431CMS#PBF, the LTC2433-1IMS#PBF uniquely combines 16-bit precision, 4µA autosleep, integrated 50/60Hz rejection, and 10-lead MSOP footprint - making it optimal for space-constrained, mains-immune, battery-operated sensor nodes.

Availability

LTC2433-1IMS#PBF is available at Aetrix Electronics and suitable for weight scales, strain-gage transducers, direct temperature measurement, and gas analyzers requiring stable component supply and long-term manufacturability.

Supply support for LTC2433-1IMS#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. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC2433-1IMS#PBF belongs to ADI's precision delta-sigma ADC product line, designed specifically for low-power, high-accuracy sensor digitization in electrically noisy environments - emphasizing autonomous noise rejection, rail-to-rail flexibility, and minimal external component count.

FAQ

What is the conversion time of the LTC2433-1IMS#PBF when using the internal oscillator?

The LTC2433-1IMS#PBF has a fixed conversion time of 146.7ms when operating with its internal oscillator (FO = GND). This value is guaranteed across the full temperature range (–40°C to +85°C) and supply voltage (2.7V–5.5V), and includes complete digital filter settling with no latency - the 19-bit output corresponds exactly to the analog input sampled at the start of the conversion cycle. The LTC2433-1IMS#PBF does not require additional settling time after conversion completion.

Can the LTC2433-1IMS#PBF operate with a 100mV reference voltage while maintaining 16-bit resolution?

Yes, the LTC2433-1IMS#PBF supports differential reference voltages as low as 100mV and maintains full 16-bit resolution with no missing codes. At 100mV VREF, the LSB size is 1.5µV, and the 1.45µV RMS noise remains constant - resulting in effective resolution exceeding 16 bits for low-level signals. This capability is explicitly guaranteed in the datasheet and enables high-fidelity digitization of microvolt-level sensor outputs without amplification.

How does the FO pin configure the LTC2433-1IMS#PBF for 50Hz/60Hz rejection?

The FO pin configures the LTC2433-1IMS#PBF by selecting the clock source: grounding FO (FO = 0V) activates the internal oscillator and configures the digital filter for simultaneous ≥87dB rejection from 49Hz to 61.2Hz. Driving FO with an external clock f_EOSC disables the internal oscillator and sets the notch center to f_EOSC/2560 ±4%. The LTC2433-1IMS#PBF automatically detects the presence of an external signal and transitions modes without firmware intervention.

Is the LTC2433-1IMS#PBF pin-compatible with other devices in the LTC24xx family?

The LTC2433-1IMS#PBF is pin-compatible with the LTC2431 and LTC2411 in the 10-lead MSOP package, sharing identical pin assignments for VCC, REF+, REF–, IN+, IN–, GND, CS, SDO, SCK, and FO. However, functional differences exist - the LTC2431 is 20-bit and lacks the FO pin's notch configuration, while the LTC2411 is 24-bit and uses different timing. The LTC2433-1IMS#PBF retains full electrical and mechanical compatibility for drop-in replacement where 16-bit resolution and dual-frequency rejection are sufficient.

What is the meaning of the 19-bit output format of the LTC2433-1IMS#PBF?

The LTC2433-1IMS#PBF outputs a 19-bit serial frame: Bit 18 is the end-of-conversion (EOC) flag, Bit 17 is a dummy zero, Bit 16 is the sign bit (SIG), Bit 15 is the MSB, and Bits 14–0 are the remaining 15 data bits - totaling 16 data bits. Bits 16 and 15 together indicate overrange (11) or underrange (00). This format enables real-time EOC interrupt generation, sign-aware data interpretation, and unambiguous fault detection - all without requiring additional status registers or command cycles.