Maxim Integrated MAXQ7666 - Manual (Page 78)

MAXQ7665/MAXQ7666 User’s Guide
2-6
2.2 Power-Supply/Supervisory Monitoring Registers
The MAXQ7665/MAXQ7666 power-supply/supervisory monitoring peripheral registers are described here. All these peripheral regis-
ters are directly accessible by the microcontroller through the module/index address.
2.2.1 Voltage Monitor Control Register (VMC)
The VMC register contains the DVDD and DVDDIO voltage-monitor threshold select bits. This register is cleared to a default value of
0000h by all forms of reset except bits 1 and 0, which are cleared by power-on reset only.
Register Description: Voltage Monitor Control Register
Register Name: VMC
Register Address: Module 05h, Index 00h
Bits 15 to 6: Reserved. Read 0, write ignored.
Bits 5, 4: DVDDIO Brownout Interrupt Threshold Bits 1, 0 (VIOBI1, VIOBI0). These bits are used to select the brownout interrupt
threshold level for the DVDDIO voltage supply. An interrupt flag (VIOBI) is set if the DVDDIO brownout detection is enabled (VIBE = 1
in the APE register) and the DVDDIO voltage falls in the threshold range selected in the following table. To convert the interrupt flag to
an interrupt, the DVDDIO brownout interrupt enable bit (VIOBIE in the AIE register) must be set. Also, global interrupt mask bits IM5
(in the IMR register) and IGE (in the IC register) must be enabled.
Bit # 15 14 13 12 11 10 9 8
Name — — — — — — — —
Reset 0 0 0 0 0 0 0 0
Access r r r r r r r r
Bit # 7 6 5 4 3 2 1 0
Name — — VIOBI1 VIOBI0 VDBI1 VDBI0 VDBR1 VDBR0
Reset 0 0 0 0 0 0 0 0
Access r r rw rw rw rw rw rw
VIOBI1:VIOBI0
BROWNOUT INTERRUPT THRESHOLD
RANGE (V)*
00 4.25–4.74 (default)
01 4.30–4.79
10 4.35–4.84
11 4.40–4.89
r = read, w = write
Note: The VDBR1 and VDBR0 bits are reset only by POR. Other bits are cleared by all forms of reset.
* Reconfirm the values provided in this table with those in the latest MAXQ7665 and MAXQ7666 data sheets.
Maxim Integrated