Voltage reference buffer (VREFBUF) RM0453
620/1461 RM0453 Rev 1
20.3 VREFBUF registers
20.3.1 VREFBUF control and status register (VREFBUF_CSR)
Address offset: 0x00
Reset value: 0x0000 0002
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res.
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Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. VRR VRS HIZ ENVR
rrwrwrw
Bits 31:4 Reserved, must be kept at reset value.
Bit 3 VRR: Voltage reference buffer ready
0: the voltage reference buffer output is not ready.
1: the voltage reference buffer output reached the requested level.
Bit 2 VRS: Voltage reference scale
This bit selects the value generated by the voltage reference buffer.
0: Voltage reference set to V
REF_OUT1
(around 2.048 V).
1: Voltage reference set to V
REF_OUT2
(around 2.5 V).
Bit 1 HIZ: High impedance mode
This bit controls the analog switch to connect or not the V
REF+
pin.
0: V
REF+
pin is internally connected to the voltage reference buffer output.
1: V
REF+
pin is high impedance.
Refer to Table 120: VREF buffer modes for the mode descriptions depending on ENVR bit
configuration.
Bit 0 ENVR: Voltage reference buffer mode enable
This bit is used to enable the voltage reference buffer mode.
0: Internal voltage reference mode disable (external voltage reference mode).
1: Internal voltage reference mode (reference buffer enable or hold mode) enable.