EM260-RCM-USART-R Ember, EM260-RCM-USART-R Datasheet - Page 19
![EM260 RCM BOARD](/photos/14/9/140937/em260-rcm-usart-r_sml.jpg)
EM260-RCM-USART-R
Manufacturer Part Number
EM260-RCM-USART-R
Description
EM260 RCM BOARD
Manufacturer
Ember
Type
Transceiver, 802.15.4/ZigBeer
Datasheet
1.EM260-RCM-USART-R.pdf
(54 pages)
Specifications of EM260-RCM-USART-R
Frequency
2.4GHz
For Use With/related Products
EM260
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
636-1025
4.11 Clock Sources
•
Additionally, the digital domain counts 1,024 clock edges on the 24MHz crystal before releasing the reset to
the main digital core.
Table 11 lists the features of the EM260 POR circuitry.
The EM260 integrates two oscillators: a high-frequency 24MHz crystal oscillator and a low-frequency internal
10kHz RC oscillator.
4.11.1 High-Frequency Crystal Oscillator
The integrated high-frequency crystal oscillator requires an external 24MHz crystal with an accuracy of
±40ppm. Based upon the application Bill of Materials and current consumption requirements, the external
crystal can cover a range of ESR requirements. For a lower ESR, the cost of the crystal increases but the
overall current consumption decreases. Likewise, for higher ESR, the cost decreases but the current
consumption increases. Therefore, the designer can choose a crystal to fit the needs of the application.
Parameter
VDD_PADS POR release
VDD_PADS POR assert
1.8V POR release
1.8V POR hysteresis
The 1.8V POR cell holds the main digital core in reset until the regulator output voltage rises above a
threshold.
Table 11. POR Specifications
Page 19
Min.
1.35
0.08
1.0
0.5
Typ.
1.2
0.6
1.5
0.1
Max.
1.65
0.12
1.4
0.7
EM260
120-0260-000J
Unit
V
V
V
V