
System Control Registers
259
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
System Control
4.2.25 LDOSPCTL Register (Offset = 0x1B4) [reset = 0x18]
LDO Sleep Power Control (LDOSPCTL)
This register specifies the LDO output voltage in sleep mode. This register should be configured while in
run mode. If the VADJEN bit is set, writes can be made to the VLDO field within the provided encodings.
lists the maximum clock frequencies with respect to LDO voltage.
Table 4-37. Maximum System Clock and PIOSC
Frequency with Respect to LDO Voltage
Operating Voltage
(LDO)
Maximum System
Clock Frequency
PIOSC
1.2 V
120 MHz
16 MHz
0.9 V
30 MHz
16 MHz
LDOSPCTL is shown in
and described in
Return to
Figure 4-31. LDOSPCTL Register
31
30
29
28
27
26
25
24
VADJEN
RESERVED
R/W-0x0
R-0x0
23
22
21
20
19
18
17
16
RESERVED
R-0x0
15
14
13
12
11
10
9
8
RESERVED
R-0x0
7
6
5
4
3
2
1
0
VLDO
R/W-0x18
Table 4-38. LDOSPCTL Register Field Descriptions
Bit
Field
Type
Reset
Description
31
VADJEN
R/W
0x0
Voltage Adjust Enable.
This bit enables the value of the VLDO field to be used to specify the
output voltage of the LDO in sleep mode.
0x0 = The LDO output voltage is set to the factory default value in
sleep mode. The value of the VLDO field does not affect the LDO
operation.
0x1 = The LDO output value in sleep mode is configured by the
value in the VLDO field.
30-8
RESERVED
R
0x0
7-0
VLDO
R/W
0x18
LDO Output Voltage.
This field provides program control of the LDO output voltage in
sleep mode. The value of the field is used only for the LDO voltage
when the VADJEN bit is set. When using the USB module, the LDO
must be configured to 1.2 V.
0x12 = 0.90 V
0x13 = 0.95 V
0x14 = 1.00 V
0x15 = 1.05 V
0x16 = 1.10 V
0x17 = 1.15 V
0x18 = 1.20 V
All other values are reserved.