SAPH and SAPH_A Registers
536
SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
Sequencer for Acquisition, Programmable Pulse Generator, and Physical
Interface (SAPH, SAPH_A)
21.8.19 SAPHMCNF/SAPH_AMCNF Register (Offset = 2Ch) [reset = 2h]
SAPHMCNF/SAPH_AMCNF is shown in
and described in
Return to
Mode Configuration Register. This bit needs to be unlocked via SAPH_AKEY for changes
Figure 21-39. SAPHMCNF/SAPH_AMCNF Register
15
14
13
12
11
10
9
8
RESERVED
LPBE
RSV1
CPEO
R/W-0h
R/W-0h
R/W-0h
R/W-0h
7
6
5
4
3
2
1
0
RESERVED
RSV0
BIMP
R/W-0h
R/W-0h
R/W-2h
Table 21-24. SAPHMCNF/SAPH_AMCNF Register Field Descriptions
Bit
Field
Type
Reset
Description
15-12
RESERVED
R/W
0h
11
LPBE
R/W
0h
LPBE, low power bias mode enable. This bit enables the low power
bias operation mode. The selection of the operation mode shall only
be changed while the PSQ is in OFF state (changes during other
states of the PSQ causes corrupt measurement results and irregular
triggers of sub modules ba ASQ)
Reset type: BOR
0h (R/W) = For manual bias mode and regular ASQ bias mode. In
this configuration the user controls by the ASQBSW has full control
over the TxBias and RxBias switches.
1h (R/W) = Low power bias mode. In this mode the ASQ uses the
CHxEBSW and PGABSW as auxiliary values to achieve faster
channel setting on reactive input loads. The ASQ has full controls
over the bias switch multiplexer.
10-9
RSV1
R/W
0h
Reserved for future use
Reset type: BOR
8
CPEO
R/W
0h
Charge pump explicitly on. This bit enables the charge pump of the
input multiplexer.
Reset type: BOR
0h (R/W) = Charge pump is turned on by SDHS and ASQ related
requests only.
1h (R/W) = Charge pump is turned on regardless of SDHS and ASQ
related charge pump requests.
7-4
RESERVED
R/W
0h
3-2
RSV0
R/W
0h
Reserved for future use
Reset type: BOR
1-0
BIMP
R/W
2h
Bias generator Impedance configuration. These bits define the
impedance of the buffers for RxBias and TxBias. While for resistive
loads the lowest impedance shows the fastest settling; is this not the
case for reactive loads.
Reset type: BOR
0h (R/W) = Buffer impedance 500 ohms for RxBias and 450 ohms
for TxBias
1h (R/W) = Buffer impedance 900 ohms for RxBias and 850 ohms
for TxBias
2h (R/W) = Buffer impedance 1500 ohms for RxBias and 1450 ohms
for TxBias
3h (R/W) = Buffer impedance 2950 Ohms for RxBias and 2900
Ohms for TxBias