STMicroelectronics STA5620C

Overview

STA5620C from STMicroelectronics is a fully integrated GPS L1 RF front-end receiver IC that down-converts 1575.42 MHz GPS signals to a 4.092 MHz low-IF output, delivers SIGN/MAG 2-bit ADC outputs and 16.368 MHz GPS_CLK, operates at 2.7 V typical supply, features on-chip programmable PLL and crystal oscillator (10–40 MHz), and is housed in a VFQFPN32 (5×5 mm) package for portable navigation systems.

For engineers reviewing the STA5620C datasheet, STA5620C pinout, STA5620C application, or STA5620C equivalent, this device serves as a complete GPS RF receiver solution requiring no external IF filtering or gain control circuitry, with SPI-configurable power modes, integrated AGC loop, and ESD-hardened (2 kV HBM) I/Os for robust embedded GNSS designs.

Technical Context

The STA5620C implements a low-IF architecture (f_IF = 4f_O = 4.092 MHz) using a quadrature image-reject mixer driven by an on-chip LC-VCO, achieving ≥20 dB image rejection and <4.5 dB noise figure. Its RF amplifier, mixer, IF filter, VGA chain, and 2-bit ADC are monolithically integrated in BiCMOS SiGe technology.

It embeds a fully programmable integer-N PLL (R-divider: 1–63; N-divider: 56–4095), charge pump current selectable in 50 µA steps (50–200 µA), and a crystal oscillator supporting TCXO input or 10–40 MHz crystals with buffered XTAL_CLK output. AGC is implemented via internal integration of MAG output to regulate VGA gain and maintain ~33% MAG duty cycle.

Key Specifications

Pinout & Package

STA5620C is packaged in a 32-pin VFQFPN (Very Thin Quad Flat No-lead) with 0.5 mm pitch, 5 mm × 5 mm body, and exposed thermal pad for enhanced heat dissipation in GPS modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar GPS RF front-end applications.

Compared with MAX2769CTJ+ and GN101L, the STA5620C uniquely combines low-IF architecture, on-chip crystal oscillator with buffered XTAL_CLK, self-regulating AGC, and hierarchical SPI-controllable power modes - making it optimal for cost-sensitive, battery-powered GPS L1-only applications demanding design flexibility and timing autonomy.

Availability

STA5620C is available at Aetrix Electronics and suitable for portable navigation devices, automotive telematics units, asset tracking modules, and drone positioning systems requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for STA5620C 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

STMicroelectronics is a global semiconductor leader specializing in microcontrollers, analog ICs, MEMS, and automotive-grade chips, with manufacturing facilities across Europe, Asia, and the Americas.

The STA5620C belongs to ST's GPS RF front-end product line, designed specifically to deliver highly integrated, low-power, and ESD-hardened GPS L1 receivers for space-constrained and battery-operated navigation equipment.

FAQ

What is the function of the AGC_CTRL pin?

The AGC_CTRL pin provides the analog control voltage for the internal variable gain amplifiers. It is driven by an on-chip integrator that processes the MAG output to maintain a nominal 33% duty cycle. An external capacitor (~10 µF) is required for loop stability; bypassing this pin with a fixed voltage disables automatic gain control.

Can STA5620C operate with a TCXO instead of a crystal?

Yes - the XTAL_IN pin accepts an external TCXO signal up to 40 MHz. When used, the internal crystal oscillator is disabled, and XTAL_CLK becomes a buffered copy of the TCXO input. This configuration improves frequency stability and reduces temperature-induced timing drift in precision GNSS applications.

How does the power control logic work between CHIP_EN and RF_EN?

CHIP_EN is the master enable: low → standby (1 µA). When high, RF_EN determines functionality - low enables only crystal oscillator and one clock output (XTAL_CLK or GPS_CLK per MODE pin), while high activates the full RF chain. MODE also selects which clock is enabled in clock-only mode.

Is the GPS_CLK output derived from the crystal or VCO?

GPS_CLK (16.368 MHz) is generated by dividing either the crystal oscillator output or the VCO signal by 96, selected via SPI register configuration. This allows synchronization to either the stable crystal reference or the phase-locked VCO output, depending on system timing architecture requirements.