T-Mobile's G1: Google's Android OS emerges
Discover some interesting facts about the two primary PCBs (printed-circuit boards) inside the premier Google Android offering.
By Brian Dipert, Senior Technical Editor -- EDN, September 17, 2009
The myTouch 3G (also known as the HTC Magic), T-Mobile's second Google Android-OS-based and HTC-designed handset, recently became available for purchase. More svelte and with a more responsive touchscreen than its predecessor, the G1 (also known as the HTC Dream), the myTouch 3G conversely relies exclusively on an on-screen virtual keyboard. After peeling away the G1's oft-preferred physical keyboard, my Prying Eyes partners at phoneWreck discovered some interesting facts about the two primary PCBs (printed-circuit boards) inside the premier Google Android offering.
1. T-Mobile's UMTS (Universal Mobile Telecommunications System) cellular-data network leverages the WCDMA (wideband-code-division/multiple-access), 1700- and 2100-MHz bands in the United States, whereas GSM (global-system-for-mobile)-communication competitor AT&T, which currently touts a more extensive 3G coverage footprint, employs 850- and 1900-MHz spectrum slices. You'll therefore see some unique pieces of silicon in the G1 versus, say, the BlackBerry Bold (see "Trolling for gold in the BlackBerry Bold," EDN, May 28, 2009, pg 20). Avago's ACPM-7381 and ACPM-7391 UMTS power amplifiers, along with TriQuint's ALM-1412 quadband power-GSM amplifier, together mate to Qualcomm's RTR6285 RF transceiver and PM7540 power-management IC. Avago also supplies the ALM-1412 GPS (global-positioning-system) amplifier.
2. The multidie, single-package memory subsystem sandwiches 256 Mbytes of Samsung's NAND flash memory and 128 Mbytes of that company's DDR SDRAM. T-Mobile bundles a 1-Gbyte microSD (secure-digital) card with the handset; the memory-module interface is higher-capacity microSDHC (secure-digital-high-capacity)-compatible.
3. AKM's AK-7986A six-axis electronic compass supplements the G1's accelerometer and GPS capabilities to provide the handset with a rich set of location, motion, and direction statistics.
4. Qualcomm's 528-MHz MSM7201A baseband processor, which embeds GPS and audio DAC/ADC functions, acts as the brains of the G1. Curiously, HTC augmented the G1's logic with a Xilinx XC2C128 CoolRunner-II CPLD, which HTC has also employed in past PDA and smartphone designs. Although the CPLD seemingly runs counter to the integration- and cost-optimized focus of a high-volume consumer-electronics device, it also enables HTC to easily augment and update hardware capabilities both on the manufacturing line and in the field.
5. For those of you who prefer old-fashioned but reliable wires, SMSC's (Standard Microsystems Corp's) USB3316 USB (Universal Serial Bus) controller has you covered.
6. The device has 802.11b/g Wi-Fi- and Bluetooth-connectivity options. The Texas Instruments WL1251B transceiver and companion WL1251FE power amplifier handle Wi-Fi, and the company's BRF6300 chip handles Bluetooth.
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Not shown are the G1's 3.2M-pixel still-image-only camera based on Aptina's (formerly Micron's) MT9T013D sensor and Analog Devices' AD5398 autofocus-capable lens-coil driver; the Sharp-supplied 3.2-in., 320×480-pixel-resolution and 65,536-color LCD; and the 1150-mAhr battery.
