Texas Instruments 3138 155 232931 manual Manand 0x21 Manual signal and override register1

CC2420

MANAND (0x21) - Manual signal AND override register1

	Bit	Field Name	Reset	R/W
15		VGA_RESET_N	1	R/W
14		BIAS_PD	1	R/W
13		BALUN_CTRL	1	R/W
12		RXTX	1	R/W
11		PRE_PD	1	R/W
10		PA_N_PD	1	R/W
9		PA_P_PD	1	R/W
8		DAC_LPF_PD	1	R/W
7		XOSC16M_PD	1	R/W
6		RXBPF_CAL_PD	1	R/W
5		CHP_PD	1	R/W
4		FS_PD	1	R/W
3		ADC_PD	1	R/W
2		VGA_PD	1	R/W
1		RXBPF_PD	1	R/W
0		LNAMIX_PD	1	R/W

Description

The VGA_RESET_N signal is used to reset the peak detectors in the VGA in the RX chain.

Global bias power down (1)

The BALUN_CTRL signal controls whether the PA should receive its required external biasing (1) or not (0) by controlling the RX/TX output switch.

RXTX signal: controls whether the LO buffers (0) or PA buffers

(1)should be used. Powerdown of prescaler. Powerdown of PA (negative path).

Powerdown of PA (positive path). When PA_N_PD=1 and PA_P_PD=1 the up-conversion mixers are in powerdown.

Powerdown of TX DACs.

Powerdown control of complex bandpass receive filter calibration oscillator.

Powerdown control of charge pump.

Powerdown control of VCO, I/Q generator, LO buffers.

Powerdown control of the ADCs.

Powerdown control of the VGA.

Powerdown control of complex bandpass receive filter.

Powerdown control of LNA, down-conversion mixers and front- end bias.

1For some important signals the value used by analog and digital modules can be overridden manually. This is done as follows for the hypothetical important signal IS:

IS_USED = (IS * IS_AND_MASK) + IS_OR_MASK,

using boolean notation.

The AND-mask and OR-mask for the important signals listed resides in the MANAND and MANOR registers, respectively.

Examples:

•Writing 0xFFFE to MANAND and 0x0000 to MANOR will force LNAMIX_PD≡0 whereas all other signals will be unaffected.

•Writing 0xFFFF to MANAND and 0x0001 to MANOR will force LNAMIX_PD≡1 whereas all other signals will be unaffected.

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