NXP Semiconductors TDA9901TS/C3,118

Overview

TDA9901TS/C3,118 from NXP Semiconductors is a wideband differential digital-controlled variable gain amplifier (VGA) with 130 MHz −3 dB bandwidth, 24 dB digitally programmable gain range in 6 dB steps, and dual-mode (transparent/latched) AGC control. It operates from 4.75–5.25 V analog and 3.0–5.25 V digital supplies, delivering low 125 nV/√Hz output noise density at 30 dB gain, and is optimized for IF signal conditioning in wireless infrastructure receivers.

For engineers reviewing the TDA9901TS/C3,118 datasheet, TDA9901TS/C3,118 pinout, TDA9901TS/C3,118 application, or TDA9901TS/C3,118 equivalent, this device supports fast gain switching with ≤3.6 ns settling time, differential ADC driving (e.g., ADC1206S055), and PECL/TTL/CMOS-compatible digital interface - critical for high-linearity, low-phase-error AGC loops in fixed-network and instrumentation systems.

Technical Context

The TDA9901TS/C3,118 implements a fully differential signal path with high-impedance differential inputs and low-impedance differential outputs, supporting both single-ended and differential clock inputs (TTL, CMOS, or PECL). Its internal Gray-coded 3-bit digital control (GRAY0–GRAY2) selects one of five discrete gain states (0, 6, 12, 18, or 24 dB above minimum), plus 6 dB fixed gain, yielding up to 30.5 dB maximum gain.

Two operational modes are defined by the TE pin: transparent mode enables real-time gain updates synchronized to the CLK HIGH level, while latched mode updates gain only on the rising edge of CLK. The device integrates two independent regulator outputs - CMVGA (for VGA input common-mode bias) and CMADC (for ADC input common-mode reference) - each with specified output resistance, temperature drift, and load capability.

Key Specifications

Pinout & Package

Package: SSOP20 (SOT266-1), plastic shrink small outline package, 20 leads, 4.4 mm body width, 0.65 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digitally controlled variable gain amplifier applications.

Compared with AD8370ACPZ-R7 and LMH6514MA/NOPB, the TDA9901TS/C3,118 uniquely integrates dual regulated common-mode references (CMVGA/CMADC), supports direct PECL/TTL/CMOS clocking without level shifters, and delivers optimal 130 MHz bandwidth with <3.6 ns gain settling - making it purpose-built for cost- and timing-sensitive IF amplifier designs in telecom infrastructure.

Availability

TDA9901TS/C3,118 is available at Aetrix Electronics and suitable for wireless infrastructure receivers, fixed network base stations, and test & measurement instrumentation requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TDA9901TS/C3,118 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and communication markets.

The TDA9901TS/C3,118 belongs to NXP's high-performance analog signal conditioning product line, designed specifically for digitally controlled IF amplification in wireless and wired communication infrastructure where low noise, fast gain agility, and differential interface integrity are essential.

FAQ

What is the maximum clock frequency supported by the TDA9901TS/C3,118 for gain control?

The TDA9901TS/C3,118 supports a maximum clock frequency of 52 MHz for gain switching in both transparent and latched modes. At this rate, setup time is 3.8 ns and hold time is 2.0 ns in latched mode, ensuring reliable digital control timing with standard FPGA or ASIC clock domains. Exceeding 52 MHz may cause metastability or incomplete gain transitions in the TDA9901TS/C3,118.

Does the TDA9901TS/C3,118 require external common-mode biasing when driving a differential ADC?

No, the TDA9901TS/C3,118 does not require external common-mode biasing when driving a differential ADC. It provides two dedicated regulated outputs - CMVGA for its own input stage and CMADC (VDDA −1.45 V typical) for ADC input biasing. CMADC delivers up to 1 mA with 26 Ω output resistance and ±0.11 mV/°C temperature drift, enabling direct connection to ADC common-mode pins like those on ADC1206S055.

How does the Gray coding scheme affect gain selection in the TDA9901TS/C3,118?

Gray coding (GRAY2–GRAY0) in the TDA9901TS/C3,118 minimizes glitches during gain transitions by ensuring only one bit changes between adjacent states. Table 7 defines five valid codes (000 to 110) corresponding to gain offsets of 0, 6, 12, 18, and 24 dB above minimum gain. This prevents momentary invalid gain states that could occur with binary coding, preserving signal integrity during rapid AGC updates in the TDA9901TS/C3,118.

What is the warm-up time requirement for optimal performance of the TDA9901TS/C3,118?

A warm-up time of 1 minute (typical) is recommended for optimal performance of the TDA9901TS/C3,118 due to on-chip regulator stabilization. During this period, internal reference voltages (CMVGA, CMADC) and bias currents settle to their final values, ensuring specified noise, gain accuracy, and PSRR performance. Operation before warm-up may exhibit temporary gain drift or elevated noise floor in the TDA9901TS/C3,118.

Can the TDA9901TS/C3,118 operate with separate analog and digital ground planes?

Yes, but VSSA and VSSD must be shorted together at a single point near the TDA9901TS/C3,118 package per the datasheet. While the device has separate analog (VSSA) and digital (VSSD) ground terminals to minimize coupling, splitting them violates the specified operating condition and risks gain instability, increased noise, or latch-up. Proper PCB layout requires a low-inductance star ground connection for both pins in the TDA9901TS/C3,118.