Mobile Devices 1.1 - 1.4 Flashcards
The display is …
usually an LCD or organic light-emitting diode (OLED) display
Backlight technology uses LEDs instead of …
- uses LEDs instead of CCFLs
- has strips of LED lights
- most LEDs do not need an inverter
- Tablets and phones, almost exclusively use LED backlighting
The inverter is a
DC –>AC
The inverter is a small circuit board installed behind the LCD panel
* flickering screens or dimness = inverter
If you see a laptop advertised as having an LED display
it’s an LCD monitor with LED backlighting
LCD monitors in use today (3)
LCD monitors in use today:
-in-plane switching (IPS)
- twisted nematic (TN)
- vertical alignment (VA).
LCDtechnology = liquid crystals and transistors to form patterns
TN has somewhat restricted
- viewing angles and not the best color reproduction
BUT - very little lag
- high refresh rates such as 240 Hz with ease
- popular choice for competitive gamers & offices
- not the best choice for high-end video needs
IPS have the best
- viewing angles and color reproduction of all
BUT - more lag than TN monitors do, but the difference is minimal in higher-end models
- graphic designers and video artists
- can mount them vertically eg programmers
VA has the best
- contrast ratios (difference between dark & bright colors)
- bit more lag (but we’re talking milliseconds here)
BUT - a jack-of-all-trades technology vs the other two options.
An OLED display supplies the light source, so there is no need for
a backlight, so power consumption is less than it is in LCD panels
- contrast ratio of OLED displays exceeds that of LCD panels, meaning that in darker surroundings, OLED displays produce better images than LCD panels produce.
- OLED monitors are the highest-quality monitors you will find on the market today.
- OLED is found in smaller devices such as smartphones
A digitiser is
A digitizer is a device that can be written or drawn on, and the content will be converted from analog input to digital images on the computer
- input from a user’s finger or a stylus
- glass of the display itself, or an overlay for the display
With a laptop, almost all components must be integrated onto the motherboard, including
onboard circuitry for the USB, video, expansion, and network ports
In most cases, this processor cannot be
removed, meaning no processor upgrades are possible.
Most laptops will run the processor in a lower power state when on battery power to extend the life of the battery. This is known as
processor throttling. The motherboard works closely with the operating system to determine if the processor really needs to run at full speed. If it doesn’t, it’s slowed down to save energy and to reduce heat
DDR SODIMMs pins range from 200 to …
200-pin DDR/DDR2
204-pin DDR3,
260-pin DDR4, and
262-pin DDR5 options
How much memory does each DDR have? (GB)
DDR 1 GB per module
DDR2 and DDR3 SODIMM up to 8 GB
DDR4 up to 32 GB
DDR5 up to 64 GB
Laptops don’t have the room for the full-sized 3.5″ hard drives that desktop computers use, instead they have
Laptops don’t have the room for the full-sized 3.5″ hard drives that desktop computers use. Smaller form factor drives at 2.5″ or 1.8″
Newer SSDs may come in the even smaller
Newer SSDs may come in the even smaller M.2 form factor.
Keyboards may need to be replaced if keys are
Keyboards may need to be replaced if keys are missing or are stuck and won’t function
The two primary forms of internal expansion used in laptops today are
The two primary forms of internal expansion used in laptops today are Mini PCIe and M.2
M.2 expansion supports
M.2 supports USB 2.0 and newer. The slowest M.2 slots support PCIe x2 and M-keyed slots support PCIe x4, making it much faster than Mini PCIe. Most M.2 expansion cards focus on communications or storage.
Mini PCIe has been the most common slot for
Mini PCIehas been the most common slot for laptop expansion cards.
Expansion cards reside inside the case of the laptop and are connected via a
a 52-pin card edge connector.
Mini PCIe cards come in two sizes:
The full-sized cards are 30 mm wide and 51 mm long. Half-sized cards are 30 mm wide and 27 mm long.
Mini PCIe cards support:
Mini PCIe cards support USB and PCIe x1 functionality, and at the same speeds.
Mini PCIe cards have 2 voltages
Mini PCIe cards have the 1.5V and 3.3V power options
Compare M.2 to PCIe
comparing it to Mini PCIe, know that it uses a narrower connector (22 mm vs. 30 mm) that has more pins (66-pin vs. 52-pin). M.2 supports USB 2.0 and newer. The slowest M.2 slots support PCIe x2 and M-keyed slots support PCIe x4, making it much faster than Mini PCIe. Most M.2 expansion cards focus on communications or storage.
Common types of cards you will see in the market include the following:
Wi-Fi network cards
Bluetooth cards
Cellular cards
SSDs
Laptops utilize DC power to energize their internal components. Therefore, any AC power source needs to be …
AC power source needs to be rectified (converted) to DC
Most laptop display backlights require _____ power
AC power. To avoid a separate external AC input, an inverter is used to convert the DC power that is supplied for the rest of the system to AC for the backlight.
converters vs inverters
converters (AC->DC)
inverters (DC->AC)
perform opposite functions
Allow a full battery discharge once a month, called
Battery calibration.