onsemi MC10E122FNR2G

Overview

MC10E122FNR2G from onsemi is a 5V ECL 9-bit non-inverting buffer IC designed for high-speed data distribution in PECL/NECL logic systems. It delivers ≤500 ps max propagation delay, supports dual supply modes (VCC = 4.2–5.7 V / VEE = 0 V or VCC = 0 V / VEE = −4.2 to −5.7 V), and operates across 0°C to +85°C. It is used in telecom clock fanout, backplane data buffering, and high-frequency test equipment signal conditioning.

For engineers reviewing the MC10E122FNR2G datasheet, pinout, applications, or equivalent options, key selection criteria include its 9-channel ECL output drive capability, internal 50 kΩ input pulldowns, guaranteed skew ≤75 ps, and PLCC-28 Pb-free tape-and-reel packaging for automated assembly.

Technical Context

The MC10E122FNR2G implements nine independent ECL buffer stages with identical input-to-output paths, enabling matched timing across all channels. Its architecture uses emitter-coupled logic with differential internal nodes and relies on external 50 Ω termination to VCC − 2.0 V for proper signal integrity.

It operates in either PECL mode (positive VCC, ground-referenced VEE) or NECL mode (ground-referenced VCC, negative VEE), with DC parameters scaling linearly with supply voltage. All VCC and VCCO pins are internally tied, requiring external connection to the same supply rail per mode.

Key Specifications

Pinout & Package

MC10E122FNR2G is housed in a 28-lead plastic leaded chip carrier (PLCC-28), case 776, with dimensions 12.32 mm × 12.32 mm × 3.56 mm (max height). The package is Pb-free and RoHS-compliant (G suffix), optimized for reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ECL buffer applications.

Compared with MC10E122FNR2G, MC100E122FNR2 offers broader temperature support but same PLCC-28 footprint, while SY100EL12ZC provides lower-voltage operation at the cost of mechanical and electrical incompatibility - neither is pin-compatible, requiring layout changes.

Availability

MC10E122FNR2G is available at Aetrix Electronics and suitable for telecom infrastructure, test & measurement equipment, and radar subsystems requiring stable component supply with Pb-free compliance and tape-and-reel delivery.

Supply support for MC10E122FNR2G 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The MC10E122FNR2G belongs to the ECLinPS™ family of high-speed ECL logic devices, engineered specifically for sub-nanosecond timing-critical applications in telecom, military, and instrumentation systems.

FAQ

What is the maximum operating frequency supported by the MC10E122FNR2G?

The MC10E122FNR2G supports a maximum toggle frequency of 800 MHz, as specified in Table 7 of its datasheet. This rating applies under both PECL (VCC = 5.0 V, VEE = 0 V) and NECL (VCC = 0 V, VEE = −5.0 V) operating conditions, with thermal equilibrium established and airflow >500 lfpm. The MC10E122FNR2G achieves this performance using emitter-coupled logic topology optimized for speed and low skew.

Does the MC10E122FNR2G require external termination resistors?

Yes, the MC10E122FNR2G requires external 50 Ω termination resistors from each Q0–Q8 output to VCC − 2.0 V, as defined in Notes 2, 4, 6, and 8 of the datasheet. This termination is mandatory to maintain proper ECL logic levels, signal integrity, and impedance matching. The MC10E122FNR2G does not integrate termination resistors; they must be placed externally on the PCB.

Can the MC10E122FNR2G operate in both PECL and NECL modes simultaneously?

No, the MC10E122FNR2G cannot operate in both PECL and NECL modes simultaneously. It is configured for one mode per power-up: either PECL (VCC = 4.2–5.7 V, VEE = 0 V) or NECL (VCC = 0 V, VEE = −4.2 to −5.7 V). The MC10E122FNR2G's internal circuitry is hardwired for single-mode operation; mixing supplies violates absolute maximum ratings and may damage the device.

What is the purpose of the internal 50 kΩ pulldown resistors on the MC10E122FNR2G inputs?

The internal 50 kΩ pulldown resistors on D0–D8 ensure defined logic LOW states when inputs are left unconnected or driven by open-collector/open-emitter sources. This eliminates the need for external biasing components in many configurations, simplifying design and reducing BOM count. The MC10E122FNR2G leverages these resistors to improve robustness against floating inputs in test fixtures or during configuration changes.

Is the MC10E122FNR2G pin-compatible with the MC100E122FNR2?

Yes, the MC10E122FNR2G is pin-compatible with the MC100E122FNR2 - both use identical PLCC-28 footprints, pin assignments, and power/signal connections as shown in Figure 1 and Table 1. However, the MC10E122FNR2G is rated for 0°C to +85°C operation, while the MC100E122FNR2 extends to −40°C, making them mechanically interchangeable but thermally differentiated.