maxq7670aatl+ Maxim Integrated Products, Inc., maxq7670aatl+ Datasheet - Page 21

• Manufacturer Part Number: maxq7670aatl+
• Description: Microcontroller With 12-bit Adc, Pga, 64kb Flash, And Can Interface
• Manufacturer: Maxim Integrated Products, Inc.

The DVDD reset supervisor resets the MAXQ7670A
when the +2.5V DVDD falls below the reset threshold.
The processor remains in reset until DVDD returns
above the reset threshold. The µC does not execute
commands in reset mode. See Figure 6 for the µC
response to DVDD brownout and reset.
Refer to the MAXQ7670 User’s Guide for detailed pro-
gramming information, and a more thorough descrip-
tion of POR and brownout behavior.
The integrated 3.3V 50mA linear regulator or an exter-
nal 3.3V supply powers AVDD. The integrated 3.3V reg-
ulator is inactive upon power-up. Enable the integrated
regulator with software programming after power-up.
When using an external supply, connect a regulated
3.3V supply to AVDD after applying DVDDIO.
Figure 6. DVDD Brownout and Reset Behavior
NOMINAL
DVDD (+2.5V)
+2.25V
DGND
DVLVL FLAG
(ASR[14])
DVBI FLAG
(ASR[4])
+2.38V
Internal 3.3V Linear Regulator
______________________________________________________________________________________
PGA, 64KB Flash, and CAN Interface
BROWNOUT
INTERRUPT
(BOI)
Microcontroller with 12-Bit ADC,
INTERNAL RESET
BROWNOUT
RESET OUTPUT
RESET
(BOR)
The integrated 2.5V 50mA linear regulator or an exter-
nal 2.5V supply applied at DVDD powers DVDD.
Connect REGEN2 to GNDIO to enable the integrated
regulator. Connect REGEN2 to DVDDIO to use an
external supply. When using an external supply, con-
nect a regulated 2.5V supply to DVDD after applying
DVDDIO.
Both internal linear regulators are capable of supplying
up to 50mA each. When using the regulators to power
AVDD and DVDD and to provide power to external
devices, make sure DVDDIO’s power input can source
a current greater than the sum of the MAXQ7670A sup-
ply current and the load currents of the two regulators.
FLAG ARBITRARILY
CLEARED BY µC
BOR STATE
DVDDIO Current Requirements
Internal 2.5V Linear Regulator
VDBE BIT SET BY µC
THRESHOLD RANGE
DVDD BROWNOUT
INTERRUPT
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