ML7344C datasheet(75/154 Pages) LAPIS

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FEDL7344C/E/J-05

ML7344C/E/J

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(3) IDLE detection mode

IDLE detection mode continues CCA untill IDLE detection. Idle detectin CCA will be executed when

RX_ON is issued while CCA_EN(CCA_CTRL: B0 0x39(4)])=0b1, CCA_CPU_EN(CCA_CTRL: B0

0x39(5)])=0b0 and CCA_IDLE_EN(CCA_CTRL: B0 0x39(6)])=0b1 are set.

Like normal mode, CCA judgement is determined by average ED value in [ED_RSLT: B0 0x3A] register and

CCA threshold defined by [CCA_LVL: B0 0x37] register. IF average ED value exceeds the CCA threshold

value, it is considered as “BUSY”. And CCA_RSLT[1:0]([CCA_CTRL: B0 0x39(1-0)]) =0b01 is set.

If average ED value is smaller than CCA threshold value and maintains IDLE detection period which is

defined by IDLE_WAIT[9:0] of the [IDLE_WAIT_L: B0 0x3B], [IDLE_WAIT_H: B0 0x3C] registers. it is

considered as “IDLE”. And CCA_RSLT[1:0] =0b00 is set. For details operation of CCA_IDLE_WAIT[9:0],

please refer to ”IDLE detection for longer period”.

In IDLE detection mode, only when IDLE is detected, CCA completion interrupt (INT[18] group3) is

generated. After IDLE detection, CCA_EN and CCA_IDLE_EN are reset to 0b0.

Upon clearing CCA completion interrupt, CCA_RSLT[1:0] are reset to 0b00. Therefore CCA_RSLT[1:0]

should be read before clearing CCA completion interrupt.

If an ED value exceeds the value defined by [CCA_IGNORE_LVL: B0 0x36] register, as long as a given ED

value is included in the averaging target of ED value calculation, IDLE judgement is not performed. In this

case, if average ED value is smaller than CCA threshold level, IDLE determination is not performed and

CCA_RSLT[1:0] indicates 0b11. CCA operation continues until given ED value is out of averaging target and

“IDLE” is determined. For details of ED value exceeding [CCA_IGNORE_LVL: B0 0x36] register, please

refer to ”IDLE determination exclusion under strong signal input”.

ML7344C Datasheet(PDF) 75 Page - LAPIS Semiconductor Co., Ltd.