Over Temperature Effects of Gm_critical | A Technical Review

The emergence of the IoT has accelerated the trend towards lower power consumption on many MCU and RF chipsets, pressuring IC designers to wring out every bit of energy savings in their circuits. The consequence, pertaining to the clocking scheme, is usually a weaker oscillator loop amplifier starved of transconductance (gm). The reduced power consumption has the potential to severely affect analog circuits, such as the Pierce oscillator.

The Pierce oscillator driving quartz crystals is one of the most common circuits in the electronics industry. Present in almost every microcontroller, RF chipsets, and many other IC’s, this circuit is the true workhorse of timing in almost every device developed today. As most design engineers employ negative resistance analysis to assess closed-loop dynamics, some may ignore another very significant metric – gm_critical.

As the name implies, gm_critical can be defined as the level of critical value of closed-loop transconductance mandatory to keep the amplifier in linear region, while maintaining sufficient forward gain at the desired phase shift of (n*2π). The closed-loop overall gain margin (GM) is mathematically represented as:

GM = gm / gm_critical ………. (1)

Whereas; gm = oscillator loop amplifier’s intrinsic transconductance (µA/V, or mA/V)
gm_critical = closed-loop transconductance needed to keep the amplifier in linear region with sufficient forward gain at the desired phase shift (µA/V, or mA/V)

It is a well-established industry figure of merit to target GM > 5, with minimum value of 3. With the reduction in the intrinsic gm value, it is paramount to simultaneously reduce the gm_critical needed for sustained oscillations.

It should be noted that gm_critical has significant dependence on the external resonator’s electrical characteristics at the desired resonant frequency and is outlined in equation (2).

gm_critical = 4 * ESR * (2πF)2 * (C0 + CL)2 ………… (2)

From equation (2) it is evident that any significant reduction in gm must be counter-balanced with a reduction in gm_critical to ensure that the closed-loop overall margin (GM) remains the same. For instance, consider the following example:

gm = 2.7 µA/V; GM = 5; then gm_critical = 0.54 µA/V maximum
Now, if the gm is reduced to 1.0 µA/V, to keep GM = 5; the gm_critical = 0.20 µA/V maximum

In equation (2) the three critical parameters that determine the feasibility of this counter-balance are the ESR, C0 and CL of the Quartz Crystal. To achieve lower gm_critical, all three of these parameters must be simultaneously reduced to ensure proper overall gain margin (GM), while the oscillator amplifier’s transconductance gm is lowered.

As the power optimized silicon expands its domination of the electronic industry, reducing the intrinsic gm, the gm_critical metric is the most important criteria to ensure robust oscillator loop performance.

Abracon’s family of newly released Performance Optimized IoT Crystals have been engineered to specifically address the falling transconductance values across the industry and are compatible with industry’s lowest gm_critical designs. The ABM8W/ABM10W/ABM11W/ABM12W MHz series are guaranteed to operate with gm_critical as low as 3.55mA/V for 50MHz operation. The ABS06W/ABS07W 32.768kHz Tuning Fork Crystals are guaranteed to operate with industry lowest gm_critical value of 0.276µA/V @ 25°C in 2.0×1.2×0.6mm and 0.191µA/V @ 25°C in 3.2×1.5×0.9mm packages.

Plots A and B represent over extended temperature oscillation sustainability matrix of these state-of-the art 32.768kHz solutions ideally suited for energy saving RTC applications.

As transconductance (gm) of most Pierce oscillators dive to unprecedented low levels, quartz crystals have to adapt to maintain sustainable oscillations. Abracon has embraced and overcome this challenge by designing and producing, lower plating load capacitance (CL) and lower equivalent series resistance (ESR) Crystals, while simultaneously lowering the (electrode package) capacitance C0.

Meeting the lowest gm_critical requirements demanded by energy saving MCUs and RF chipsets means guaranteed low CL, ESR and C0. Abracon’s specialized design and processing techniques address this paradigm shift and brings both MHz and kHz Performance Optimized Quartz Crystals to the market. Uniquely engineered for the IoT/Wearable/Consumer Electronics market, these crystals are ready for the future of lower power engineering.

Luscombe Rocky Mountain announced new Abracon Manufacturer’s Representative in Colorado, Utah, Idaho, Montana, and Wyoming

Austin, TX – Abracon, LLC (Abracon), a leading global manufacturer of passive & electromechanical timing, synchronization, power, connectivity, and RF solutions, announces Luscombe Rocky Mountain as the new manufacturer’s representative with coverage in Colorado, Utah, Idaho, Montana, and Wyoming.

Luscombe RM has been delivering hardware solutions to the Rockies for over 30 years, offering a focused supplier base, industry expertise, and a customer centric approach. Their addition to our team extends valuable guidance with technical acumen to our mutual customers in the region.

“Luscombe RM shares many common values with Abracon,” said Joan Lanoux, North Central Regional Sales Manager with Abracon. “These include a legacy of exceptional technical knowledge, diligence in providing quality solutions, and vast sales experience. I appreciate the genuine enthusiasm they have towards finding the best technical solutions for their customers.”

This partnership assures optimal in-territory support for existing and new customers, accelerating their time to market using Abracon’s broad product solutions and leading edge technologies.

“Luscombe Rocky Mountain is excited to begin our new partnership with Abracon. We look forward to engaging and supporting our customers with Abracon’s IoT optimized portfolio” said Bryan Fluegel, Partner at Luscombe Rocky Mountain.

About Abracon, LLC
Founded in 1992, and headquartered in Spicewood, Texas, Abracon is a leading global manufacturer of passive and electromechanical timing, synchronization, power, connectivity and RF solutions. Abracon offers a wide selection of quartz timing crystals and oscillators, MEMS oscillators, real time clocks (RTC), Bluetooth modules, ceramic resonators, SAW filters and resonators, power and RF inductors, transformers, circuit protection components and RF antennas and wireless charging coils. The company is ISO9001-2008 certified with design & application engineering resources in Texas and sales offices in Texas, California, China, Taiwan, Singapore, Scotland, Israel, Hungary, UK, and Germany. Abracon’s products are offered through its global distribution network. For more information about Abracon, visit www.abracon.com.

Abracon and TTI Inc Announce Asia Partnership

Austin, TX – Abracon, LLC (Abracon), a leading global manufacturer of passive & electromechanical timing, synchronization, power, connectivity and RF solutions, announces Asia partnership with TTI, Inc., the leading authorized distributor of interconnect, passive, electromechanical and discrete components. The Asia partnership is an extension of TTI and Abracon’s existing global distribution agreement which was announced by both companies in April 2017.

Michael Calabria, Abracon’s CEO said, “With mutual focus on IP&E and discrete components, the two companies are leaders in the industry and a natural fit. As many users of electronics components rely on the supply chain and go-to-market benefits provided by distributors, Abracon is excited to partner with TTI to support its highly valued customers.”

Anthony Chan, President of TTI Asia Pacific, commented on the addition of Abracon to TTI Asia’s specialized line card, “I am pleased to welcome Abracon to be a TTI business partner in Asia. Abracon offers a wide selection of latest technologies in frequency control, timing and synchronization. I am confident that our partnership in Asia will create additional value to our customers.”

About TTI
TTI, Inc. a Berkshire Hathaway company, is an authorized, specialty distributor of interconnect, passive and electromechanical (IP&E) components and the distributor of choice for industrial and consumer electronics manufacturers worldwide. Broader and deeper inventory, leading-edge products and custom supply chain solutions have established TTI as the leading specialist in electronic component distribution. Globally, the company maintains 1.2 million cubic feet of dedicated warehouse space containing over 850,000 component part numbers. Along with its subsidiaries, Mouser Electronics and Sager Electronics, TTI employs more than 4,700 employees and is represented in over 100 locations throughout North America, Europe and Asia. For more information about TTI, visit www.ttiinc.com.

About Abracon, LLC
Founded in 1992, and headquartered in Spicewood, Texas, Abracon is a leading global manufacturer of passive and electromechanical timing, synchronization, power, connectivity and RF solutions. Abracon offers a wide selection of quartz timing crystals and oscillators, MEMS oscillators, real time clocks (RTC), Bluetooth modules, ceramic resonators, SAW filters and resonators, power and RF inductors, transformers, circuit protection components and RF antennas and wireless charging coils. The company is ISO9001-2008 certified with design & application engineering resources in Texas and sales offices in Texas, California, China, Taiwan, Singapore, Scotland, Israel, Hungary, UK, and Germany. Abracon’s products are offered through its global distribution network. For more information about Abracon, visit www.abracon.com.

Abracon announces new rep, TAI Technical Sales, for East Pennsylvania, South Jersey, and Delaware Market

Austin, TX – Abracon, LLC (Abracon), a leading global manufacturer of passive & electromechanical timing, synchronization, power, connectivity and RF components announces TAI Technical Sales as the new manufacturer’s representatives serving South Jersey, Eastern Pennsylvania, and Delaware. TAI brings over 100 years of sales experience to our team with strong channel growth objectives and customer centric values.

“TAI’s mission is to offer a market advantage to our customers along with the resources they need to succeed with their designs. Partnering with Abracon perfectly aligns with this mission and provides our customers with a unique advantage, offering fast engineering support and deep industry knowledge for end market solutions. Innovative design engineers will find solutions faster and easier with the availability of Abracon products in East Pennsylvania, South Jersey, and Delaware” commented Steve Buroojy, partner at TAI Technical Sales.

TAI is a quality extension of Abracon’s core capabilities and services in the East Pennsylvania and South Jersey markets. With TAI, our customers can leverage leading knowledge and services to design-in high quality Abracon solutions.

“Between the two current partners, Steve Buroojy and Scott Bibus, and TAI members, Jim Heffernan and Joe Bierman, TAI brings over 100 years of experience to the table. Their vision for growth, channel strategy, and customer value proposition complements Abracon’s mission to provide exceptional support to our growing community of engineers. TAI is the perfect partner for Abracon in the Philadelphia territory” commented Steve Anderson, Northeast Regional Sales Manager, Abracon.

About Abracon, LLC
Founded in 1992, and headquartered in Spicewood, Texas, Abracon is a leading global manufacturer of passive and electromechanical timing, synchronization, power, connectivity and RF solutions. Abracon offers a wide selection of quartz timing crystals and oscillators, MEMS oscillators, real time clocks (RTC), Bluetooth modules, ceramic resonators, SAW filters and resonators, power and RF inductors, transformers, circuit protection components and RF antennas and wireless charging coils. The company is ISO9001-2008 certified with design & application engineering resources in Texas and sales offices in Texas, California, China, Taiwan, Singapore, Scotland, Israel, Hungary, UK, and Germany. Abracon’s products are offered through its global distribution network.

Antenna Solutions Guide available by Abracon

Abracon, LLC. (Abracon), a leading global manufacturer of frequency control, signal conditioning, clocking and magnetic components, announces availability of the Antenna Solutions Guide designed to enable quick selection of devices available within Abracon’s broad antenna offering supporting IoT, industrial and commercial RF protocols. Chip, patch, multi-band and external antennas addressing advanced protocols such as Cellular, LTE, GSM, WiFi, WLAN, Zigbee, Bluetooth, BLE, GPS, GLONASS and BEIDOU in a broad range of markets including connected lighting, wearables, industrial process control, home automation, geolocation, asset tracking, synchronization, machine to machine (M2M), networking and communications.

“The IoT has brought with it the next connectivity revolution,” says Juan Conchas, Director of Marketing with Abracon. “Abracon is committed to support antenna device solutions and optimization services for a wide range of fast growing end applications with stringent time-to-market requirements.”

“Considering there is no free lunch with respect to antenna gain, sensitivity and performance,” says Dean Clark, Senior Technical Manager with Abracon, “Abracon’s wide offering allows end users to select the optimal antenna performance and form factor. Additionally, obtaining the best efficiency, gain and bandwidth often requires tuning antennas to each individual design. Abracon’s antenna optimization service is a resource that bridges this gap for the customer.”

The latest Antenna Solutions Guide is available here: http://abracon.com/Support/antenna-solutions-guide.pdf

All antennas and antenna optimization services with part number ABAOS-5WK are available from any of Abracon’s franchised distributors.

About Abracon, LLC
Abracon is a global manufacturer of frequency control, signal conditioning, clock distribution and magnetic components. Abracon offers a wide selection of Quartz Crystals, Crystal and MEMS Oscillators, Real Time Clocks, Antennas, Bluetooth Modules, Ceramic Resonators, SAW Filters, SAW Resonators, Inductors, Transformers, RFID Tags and RJ45 Jacks. The company is ISO9001-2008 certified with design, warehouse and applications engineering resources in Texas and offices in California, China, UK and Germany. Abracon’s products are offered through its global distribution network.

Abracon announces new Director of Distribution, Chad VanDoorninck

Abracon, LLC. (Abracon), a leading global manufacturer of frequency control, signal conditioning, clocking and magnetic components, announces Chad VanDoorninck as Director, Distribution. In his new role, Chad will work with Abracon’s comprehensive network of distribution channel partners to enhance the product availability and support for end customers and EMSi Providers.

“We are happy to enlist Chad’s expertise in supporting our channel strategy,” says Mike White, VP of Global Sales. “Our customers count on the supply chain benefits that distributors bring and we believe Chad is the best fit to ensure the right inventory is properly positioned to support accelerated time to market demands.”

Chad’s previous roles include Financial Analyst, Regional Finance Manager and Account Executive with TW Telecom. With Amphenol Aerospace, he served as Regional Distribution Sales Manager and National Distribution Sales Manager for The United States, Canada and Mexico. Chad holds a Bachelor of Science in Business Administration from Colorado State University and a Master of Business Administration from Regis University.

About Abracon, LLC
Abracon is a global manufacturer of frequency control, signal conditioning, clock distribution and magnetic components. Abracon offers a wide selection of Quartz Crystals, Crystal and MEMS Oscillators, Real Time Clocks, Antennas, Bluetooth Modules, Ceramic Resonators, SAW Filters, SAW Resonators, Inductors, Transformers, RFID Tags and RJ45 Jacks. The company is ISO9001-2008 certified with design, warehouse and applications engineering resources in Texas and offices in California, China, UK and Germany. Abracon’s products are offered through its global distribution network.