Microchip Technology U2790B-NFPG3H

Overview

U2790B-NFPG3H from Atmel is a 100–1000 MHz single-ended quadrature modulator in SO16 package, featuring 90° phase control loop, –1 dBm typical RF output, 35 dB sideband suppression at 900 MHz, and low LO input requirement of –10 dBm; used in GSM and digital radio transmitters.

For engineers reviewing the U2790B-NFPG3H datasheet, U2790B-NFPG3H pinout, U2790B-NFPG3H application, or U2790B-NFPG3H equivalent, key selection criteria include LO frequency range (100–1000 MHz), sideband suppression performance, power-down mode support, and baseband input impedance matching for I/Q signal integrity.

Technical Context

The U2790B-NFPG3H integrates a duty-cycle regenerator and frequency doubler to enable precise 90° quadrature phase shifting without external calibration. Its internal bias network sets 2.5 V DC offset on baseband inputs, supporting AC-coupled differential signaling with 3.2 kΩ single-ended input impedance.

LO and RF ports are 50-Ω single-ended with VSWR ≤2.0 across operating band; phase error remains <1° and amplitude error <±0.25 dB under nominal conditions, enabling high-fidelity modulation for GMSK and other constant-envelope schemes.

Key Specifications

Pinout & Package

U2790B-NFPG3H is housed in a Pb-free SO16 surface-mount package (10.0 × 3.8 mm, 1.4 mm height) with standard 1.27 mm pitch; thermal resistance R_thJA = 110 K/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quadrature modulator applications.

Compared with ADL5375-05ACPZ-R7 and TRF3705IRGET, the U2790B-NFPG3H offers superior sideband suppression (35 dB) and lower LO drive (–10 dBm) within its 100–1000 MHz range, making it optimal for cost-sensitive, narrowband digital radio transmitters where external component count must be minimized.

Availability

U2790B-NFPG3H is available at Aetrix Electronics and suitable for GSM transmitter front-ends, base station digital radio modulators, and JDC infrastructure systems requiring stable component supply and Pb-free compliance.

Supply support for U2790B-NFPG3H 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

Atmel Corporation (now part of Microchip Technology) is a semiconductor manufacturer specializing in microcontrollers, RF ICs, and mixed-signal solutions for communications and embedded systems.

The U2790B-NFPG3H belongs to Atmel's UHF quadrature modulator product line, designed specifically for digital cellular radio systems including GSM, JDC, and ADC, emphasizing low-power, single-ended interface simplicity and factory-calibrated quadrature accuracy.

FAQ

What is the recommended LO input level for U2790B-NFPG3H?

The U2790B-NFPG3H specifies a typical LO input level of –10 dBm, with a functional range of –12 to –5 dBm depending on frequency. At 900 MHz, –10 dBm delivers optimal sideband suppression and output linearity. Lower levels increase distortion; higher levels risk saturation. The U2790B-NFPG3H's low LO sensitivity eliminates need for driver amplifiers in many designs.

Does U2790B-NFPG3H require external phase calibration components?

No, the U2790B-NFPG3H features an integrated phase control loop that provides factory-trimmed 90° quadrature accuracy with <1° phase error - eliminating external hybrids, delay lines, or calibration circuitry. Pins 15 and 16 (Phadj) support optional fine-tuning only for applications demanding >35 dB sideband suppression beyond standard performance.

What baseband input configuration does U2790B-NFPG3H support?

The U2790B-NFPG3H supports differential AC-coupled baseband inputs (pins 7/8 for I+, I– and 9/10 for Q+, Q–) with internal 2.5 V ±0.15 V bias and 3.2 kΩ single-ended input impedance. It accepts 1 V_pp differential signals and also supports DC-coupled operation with externally supplied 2.5 V bias - confirmed in Section 8.2 of the U2790B-NFPG3H datasheet.

How does the power-down mode function on U2790B-NFPG3H?

The U2790B-NFPG3H enters power-down mode when PU (pin 1) is held ≤0.5 V, reducing supply current to 1 µA. This feature enables rapid system-level power gating in battery-operated or duty-cycled transmitters. Recovery time is defined by SPU pin capacitance; with 100 pF, settling occurs in ≤10 µs - verified in Electrical Characteristics Table 5.2.

Is U2790B-NFPG3H compatible with 50-Ω RF and LO interfaces?

Yes, the U2790B-NFPG3H has fully 50-Ω matched single-ended LO (pin 12) and RF (pin 3) ports, with VSWR ≤2.0 across 100–1000 MHz. No external matching networks are required for standard 50-Ω PCB traces or connectors - confirmed in Figures 7-8 through 7-11 and Table 4.7 of the U2790B-NFPG3H datasheet.