Standard and Alternate Parts List
An overview of the key components used in the LPC1114 802.15.4 Wireless Board.
The following table lists the key components used in the LPC1114 802.15.4 Wireless Transceiver, as well as a few alternate parts that you may want to consider using in special circumstances where you require a lower operating voltage or a wider temperature range. The pros and cons of these suggested part replacements are detailed below.
Standard Parts List
These are the default parts that are used when assembling the boards, resulting in a temperature range of -10°C to 70°C
| Part | Description | Manuf. Number | Digikey | V Min | V Max | Temp Min | Temp Max | uA (Sleep) |
| B1 | Balun | 0896FB15A0100 | 712-1473-2-ND | -- | -- | -40°C | 85°C | -- |
| Q1/3 | P-Ch FET | IRLML5103TRPBF | IRLML5103PBFTR-ND | -- | -- | -55°C | 150°C | -- |
| Q4 | NPN Trans | BC817-40,215 | 568-1631-2-ND | -- | -- | -65°C | 150°C | -- |
| U1 | Transceiver | AT86RF212 | AT86RF212-ZU-ND | 1.8V | 3.6V | -40°C | 85°C | 0.2uA |
| U2 | VReg | TPS780330220DDCR | 296-23332-1-ND | -- | 5.5V | -40°C | 125°C | 0.5uA |
| U3 | MCU | LPC1114FBD48/301,1 | 568-4950-ND | 1.8V | 3.6V | -40°C | 85°C | varies |
| U4 | EEPROM | 24AA32AFT-I/OT | 24AA32AFT-I/OTTR-ND | 1.7V | 5.5V | -40°C | 85°C | 1uA |
| U5 | I2C Temp. | LM75BDP,118 | 568-4768-2-ND | 2.8V | 5.5V | -55°C | 125°C | 0.2uA |
| Y1 | XTAL | NX3225SA-
16.000000MHZ | 644-1049-2-ND | -- | -- | -10°C | 70°C | -- |
| Y2 | XTAL | NX3225SA-
12.000000MHZ | 644-1047-2-ND | -- | -- | -10°C | 70°C | -- |
Alternate Parts List
The following replacement parts may be worth considering in certain circumstances, and can be populated on special request. They offer either a wider operating temperature range (-40°C-70°C instead of -10°C to 70°C) or a lower minimum operating voltage (1.8V instead of 2.8V, though if a micro-SD card is used 3.3V will always be required).
Engineering is all about tradeoffs. Using the parts detailed below will let you run the same board with a 1.8V supply (though you'll need to change the voltage regulator for this as well, and 1.8V will rule out using a micro-SD card), and with a wider operating temperature range (-40 to 70°C), but at a marginally higher cost (~1.50€ more), with a higher power consumption in deep sleep and a slightly less accurate crystal. Obviously deciding whether these compromises are necessary or acceptable depends on the exact requirements that you have, but hopefull this information will make it easier to find the right compromise.
| Part | Description | Manuf. Number | Digikey | V Min | V Max | Temp Min | Temp Max | uA (Sleep) |
| U5 | I2C Temp. | DS75LVU+ | DS75LVU+-ND | 1.7V | 3.7V | -55°C | 125°C | 2uA |
| Y1 | XTAL | NX3225SA-
16.000000MHZ | 644-1129-2-ND | -- | -- | -40°C | 125°C | -- |
| Y2 | XTAL | NX3225SA-
12.000000MHZ | 644-1128-1-ND | -- | -- | -40°C | 125°C | -- |
U5 - I2C Temperature Sensor
- Pros: Allows the board to be run as low as 1.8V
- Cons: Higher sleep current for boards that spend most of time in deep sleep
The SD75LVU+ is SW compatible with the LM75B and can operate down to 1.7V, meaning that the entire board (except the SD card) can be run as low as 1.8V (or from the 2.2V output on the TPS780 linear regulator), resulting in a significantly lower operating current. The tradeoff, though, is that the sleep current is higher on the SD75LVU+ than the LM75B (2uA versus ~0.2uA). For devices that spend the overwhelming majority of their time in deep sleep (i.e., quickly reading a sensor once every 15 minutes) the 1.8uA saving in deep sleep may be more significant than any energy saved in active mode if the device is only active for a few hundred milliseconds.
X1/X2 - Crystals
- Pros: Wide temperature range (allowing the board to operate -40°C to 70°C versus -10 to 70°C)
- Cons: Slightly less accurate with +/50ppm freq. stability versus +/-15ppm
These crystals have a much wider temperature range (-40°C-125°C to -10°C-70°C), allowing you to operate the board over a much wider range (-40°C to 70°C is no other components are changed). They are marginally more expensive, but the main drawback is that they are slightly less accurate with +/-50ppm frequency stability versus +/-15ppm for the reduced temperature range versions.