K60P100M100SF2RM Datasheet, PDF (902/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

Functional Description
VREF_SC field descriptions (continued)
Field
10 Tight-regulation buffer enabled
11 Reserved
Description
37.3 Functional Description
The Voltage Reference is a bandgap buffer system. Unity gain amplifiers are used.
The VREF_OUT signal is available as an internal reference when it is enabled. A 100 nF
capacitor must be connected between VREF_OUT and VSSA.
The following table shows all possible function configurations of the Voltage Reference.
Table 37-5. Voltage Reference function configurations
SC[VREFEN]
0
1
1
1
1
SC[MODE_LV]
X
00
01
10
11
Configuration
Functionality
Voltage Reference disabled
Off
Voltage Reference enabled,
only the VREF bandgap is on
Startup and standby
Reserved
Reserved
Voltage Reference enabled,
VREF bandgap and tight-
regulation buffer on
VREF_OUT available for
internal and external use. 100
nF capacitor is required.
Reserved
Reserved
37.3.1 Voltage Reference Disabled, SC[VREFEN] = 0
When SC[VREFEN] = 0, the Voltage Reference is disabled, all bandgap and buffers are
disabled. The Voltage Reference is in off mode.
37.3.2 Voltage Reference Enabled, SC[VREFEN] = 1
When SC[VREFEN] = 1, the Voltage Reference is enabled, and different modes can be
set by the SC[MODE_LV] bits.
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
902
Freescale Semiconductor, Inc.