Diodes Incorporated ZLNB2012Q16TC

Overview

ZLNB2012Q16TC from Zetex is a dual-channel satellite LNB polarisation and 22 kHz tone switch controller in QSOP16 package. It provides independent H/V polarity selection, local oscillator band switching (low/high), and downfeed enable/disable per channel via TTL/CMOS-compatible outputs. Features include temperature-compensated 14.0–14.5 V polarisation threshold, 9 V receiver-absent detection, integrated tone detectors with user-adjustable RC filter, and operation from 5–8 V supply with 9 mA quiescent current. Used in Twin/Quad Universal LNBs for DVB-S reception.

For engineers reviewing the ZLNB2012Q16TC datasheet, ZLNB2012Q16TC pinout, ZLNB2012Q16TC application, or ZLNB2012Q16TC equivalent, key selection criteria include dual-channel voltage threshold accuracy, tone detection immunity to DiSEqC™ bursts, receiver-off detection logic, QSOP16 thermal performance at 80°C ambient, and direct drive capability for PIN diode switches and multiplexer ICs.

Technical Context

The ZLNB2012Q16TC implements two fully independent signal paths, each integrating a precision voltage comparator with 14.25 V nominal threshold (±0.25 V range) and ±0.5 V temperature drift over −40°C to +80°C. Each channel includes a dedicated 22 kHz tone detector with externally programmable center frequency and bandwidth via RC network.

Each channel delivers three logic outputs: HOR (horizontal/low-band), BHOR (complementary), and ENA (enable). ENA asserts low below 8 V input to indicate receiver disconnection, forcing downfeed disable. All outputs are rail-to-rail compatible with TTL, CMOS, PIN diodes, and IF amplifier switching loads.

Key Specifications

Pinout & Package

Package: QSOP16 (4.9 mm × 3.9 mm × 1.5 mm), surface-mount, moisture-sensitive level 3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LNB control applications.

Compared with MAX2022ETJ+ and STV0900, the ZLNB2012Q16TC delivers true dual-channel autonomy with integrated receiver-absent detection and 22 kHz tone immunity - enabling compact, robust, and field-proven LNB control without external logic or voltage translation.

Availability

ZLNB2012Q16TC is available at Aetrix Electronics and suitable for Twin Universal LNBs, Quad Universal LNBs, LNB switch boxes, and multi-feed satellite distribution systems requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for ZLNB2012Q16TC 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

Zetex (now part of Diodes Incorporated) is a UK-based analog semiconductor specialist focused on high-performance interface, power management, and RF solutions for consumer, industrial, and communications markets.

The ZLNB2012 belongs to Zetex's satellite front-end controller product line, designed specifically to replace discrete LNB bias and switching networks in universal LNB modules while meeting ETSI EN 301 752 compliance and field-deployed thermal reliability requirements.

FAQ

What is the purpose of the 9 V threshold on VPOL1/VPOL2 inputs?

The 9 V threshold detects absence of a connected receiver. When input voltage drops below 9 V, the corresponding ENA output goes low to disable the downfeed driver, preventing signal reflections from unterminated coaxial cables. This ensures clean RF performance even when one or more receivers are powered off or disconnected - a critical requirement in multi-feed installations.

Can ZLNB2012Q16TC operate with a 12 V supply?

No. Absolute maximum supply voltage is 12 V, but recommended operating range is strictly 5–8 V per datasheet specifications. Operating above 8 V risks exceeding internal bias limits and may cause unstable threshold behavior or accelerated parametric drift. External regulators or ZNBG-series bias generators must be used if LNB supply exceeds 8 V.

How does the tone detector reject DiSEqC™ bursts?

The tone detector uses a proprietary rectifier/smoother/comparator circuit with internal high-pass filtering above 100 kHz and optimized time constants. This design inherently attenuates DiSEqC™ 22 kHz burst envelopes (which contain strong sub-1 kHz harmonics) while preserving true 22 kHz carrier detection - verified in ETSI-compliant test setups with real-world DiSEqC™ traffic.

Is external filtering required on FIN1/FIN2 inputs?

No external filtering is required. The FIN pins accept the 22 kHz tone directly superimposed on the DC supply line. Internal op-amp gain and RC network (RP/CF) set both low-frequency cutoff and tone sensitivity. Only the specified 1.0 kΩ resistor and 10 nF capacitor per channel are needed - matching the reference design in the datasheet for guaranteed performance.