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Mobile Devices

SonyEricsson Z250i Mobile Phone Teardown

03 February 2008
The following is an overview of a teardown analysis conducted by IHS Technology Teardown Services.

Main Features / Overview

Low-cost "fashion flip phone from Sony Ericsson. Tri-band GSM/GPRS with VGA camera, WAP 2.0 XHTML Internet connectivity (even includes IrDA), but no Bluetooth. The Z250i also features a 128x160 65K color STN screen with no secondary, however features external lighted ""indicator" icons for e-mail, missed calls, etc.

Internally - this is one of the most austere Sony Ericsson designs we have seen, and it appears to feature a variant of the TI LoCosto chipset based on (a) the lack of separate RF Xcvr and (b) The application of the TWL3031 also seen in the Motofone F3, which also featured (another) version of LoCosto (different package). There is minimum silicon content in this phone - only what's necessary - no discrete audio chips, image processor, Bluetooth, FM radio, or anything other than the bare essentials.

SonyEricsson Z250i Mobile Phone Main ImageSonyEricsson Z250i Mobile Phone Main Image

Target Market

Cost-conscious consumers, and emerging market consumers looking for a stylish handset.


"Coming soon" per Sony Ericsson's website at the time of writing (August 7).

Pricing and Availability

Pricing - Unknown as not yet released. Availability: ""Possible limited market availability." Per Sony Ericsson, however on its website the product is available in four countries in the Middle East, Africa, 13 smaller countries in the Asia-Pacific region (doesn't include China, Japan, Korea…), and most of Western and Eastern Europe.

Volume Estimations

Based on Sony Ericsson's market shares, the strength and potential for sale in new emerging markets, and our estimates of market volume shipments by manufacturers and market segments (see iSuppli Design Forecast Tool (DFT) data below), we are assuming a total production volume for this model of 2 million units over a two-year lifetime.

As a reminder, teardown volume production assumptions are meant primarily to be used for our cost analysis in terms of amortized NRE and tooling costs, especially for custom components specific to the model being analyzed (mechanical components especially). Unless assumed volumes are different by an order of magnitude, minor changes in volume (say 1 million vs. 2 million) rarely have a large net effect on our final analysis because of this.

iSuppli's Design Forecast Tool (DFT) and Market Shares

As part of iSuppli's Design Forecast Tool (DFT), we forecast handset shipments by major design feature and manufacturer, as well as the number of design starts a manufacturer will have by feature set.

From our most recent revision of this tool iSuppli estimates unit shipments of 408 million GPRS handsets in the 2007 global market, and we further estimate unit shipments of 168 million tri-band 900/1800/1900 handsets in the 2007 global market.

Function / Performance

Functional testing was not performed on the Sony Ericsson Z250i.

SonyEricsson Z250i Mobile Phone Cost AnalysisSonyEricsson Z250i Mobile Phone Cost Analysis

What Is Not Included in our Cost Analysis

The total materials and manufacturing costs reported in this analysis reflect ONLY the direct materials cost (from component vendors and assorted EMS providers), AND manufacturing and test. Not included in this analysis are costs above and beyond the material manufacture of the core device itself - cost of intellectual property, royalties and licensing fees (those not already included into the per component price), software, software loading and test, shipping, logistics marketing and other channel costs including not only EMS provider and the OEM's margin, but that of other resellers. Our cost analysis is meant to focus on those costs incurred in the manufacture of the core device and exceptionally in some circumstances the packaging and literature as well.

Manufacturing NotesSony Ericsson Relationships / Manufacturing

Sony Ericsson outsources roughly two-thirds of its mobile handsets to Flextronics and a couple of Taiwanese ODMs. Sony Ericsson centralizes its internal manufacturing activities in China and leverages the EMS provider's global footprint to tap emerging markets such as India and Brazil.

Country of Origin / Volume Assumptions

This product is labeled as Made in China, furthermore, we have assumed that for this model that PCB was also populated in China, and that custom mechanicals (plastics and metals) were also sourced domestically in China.

Country of origin assumptions relate directly to the associated cost of manufacturing, where calculated by iSuppli. In the cases of ""finished" sub-assemblies (such as chargers), we do not calculate internal manufacturing costs, but rather assess the market price of the finished product in which case country of origin assumptions may or may not have a direct effect on pricing.

The issue of labor rates was revisited in Q2 2006 as we began to apply some research by one the major worldwide EMS suppliers and are now applying some of their research on total loaded costs by country and region to arrive at these new rates, which are pronouncedly higher on the low end in China. Remember that labor rates are applied directly only to hand-inserted components and systems in our bill of materials, and although regional assumptions do, these new rates do not have a direct effect on our modeled calculations of placement costs for automated SMD assembly lines.

Design for Manufacturing / Device Complexity

Most of the phones we have seen that are either clamshell or ""slider" have higher component counts due to additional mechanical and electro-mechanical complexity owing to the ""splitting" of the design into two ""halves."

In the case of the SonyEricsson Z250i, this device has a total component count of 483 of which 92 are mechanical. This puts the Z250i in-line with other competing phones with similar functionality in the clamshell form factor.

Component counts have a direct bearing on the overall manufacturing cycle times and costs, and also can increase or decrease overall yields and re-work. Our calculations of manufacturing costs factor counts and more qualitative complexities in the design. The cost of manufacturing is also, to some extent, decreased in this case because of the assumed labor rate applied for China.

Note that manual labor has a much smaller effect on auto-insertion assembly lines (for the Main PCB, for example), where manufacturing costs are much more capital equipment intensive and driven by these investment costs.

Design Notes

The Sony Ericsson Z250i is designed around a variant of TI's LoCosto chipset. This is not a 100% positive identification from markings - but rather from circumstances. Our assumption seems well founded based on (a) the non-existence of a discrete RF transceiver, (b) the application of the same power management chip as the Motofone F3 (also with LoCosto), (c) the fact that this is clearly a low-end phone where that would make sense, and (d) the fact that it is from TI for which the RF xcvr integration in low-end chipsets would be known as a LoCosto solution.

Here is a summary of the major components used in the Sony Ericsson Z250i design:

Main PCBDigital Baseband / RF

DBB - Texas Instruments - D6553BQ - Digital Baseband Processor / RF Transceiver, TI LoCosto

Baseband - Battery / Power Management

  • ABB - Texas Instruments - TWL3031FZPH - Analog Baseband / Power Management


MCP - Intel - RD38F4050L0YUQ3 - 256Mb NOR Flash, 64Mb PSRAM


PAM - Skyworks - SKY77318-12 - Quad Band, GSM/GPRS


Camera Module - Manufacturer Unknown

Image Sensor - VGA, CMOS, 1/6-inch Format - 3.6um x 3.6um Pixel Size, 2.30mm x 1.73mm Active Image Area


1.8-inch Diagonal, 65K CSTN, 128x160 Pixels

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