16-3 __________________________________________________________________________________________________________
MAXQ7667 User’s Guide
SECTION 16: POWER-SUPPLY/SUPERVISORY MONITORING
The MAXQ7667 power-supply/supervisory monitoring module supports dedicated supply pins to independently power analog, digital
I/O, and digital core functions. The analog functions, digital core, and the digital I/O can be powered from an internal regulator.
The MAXQ7667 power-supply/supervisory monitoring module includes the following features:
• Dedicated analog supply (+3.3V) pins
• Dedicated digital I/O supply (+5.0V) pins
• Dedicated digital core supply (+2.5V) pins
• On-chip +2.5V regulator with a dedicated output pin
• On-chip +3.3V regulator with a dedicated output pin
• On-chip +5.0V regulator (needs an external pass transistor for operation)
• Digital core voltage monitor
• Digital I/O voltage monitor
• Analog voltage monitor
• Preset threshold voltage level for power-on reset
• Preset threshold voltage level for digital core interrupt generation
• Preset threshold voltage level for digital I/O interrupt generation
• Preset threshold voltage level for analog interrupt generation
• Four reset sources: power-on (brownout), external, watchdog timer, and internal system
16.1 Power-Supply/Supervisory Module Pins
Table 16-1 shows the MAXQ7667 power-supply module signals.
Table 16-1. MAXQ7667 Power-Supply Module Pins
POWER-SUPPLY
SIGNA L
PIN FUNCTION
AVDD 27, 32
Analog Supp ly (+3.3V). AVDD is the power -supply pin for all analog functions. Connect to REG3P3 and
bypass with a 0.1µF capacitor to ground for self-powered operation.
AGND 28, 31, 33 Analog Ground
D V D D 6, 19, 42
D ig ital Supply Voltage (+2.5V). Connect all D V D D p ins to the same point. Connect to REG2P5 and
bypass with a 0.1µF capacitor to ground for self-powered operation.
D V D DIO 8,17, 44
I/O Supp ly Voltage (+5.0V). D V DDIO is the power-supply p in for all d ig ital input/output pins. Connect all
D V D DIO p ins to the same point.
DGN D 7, 18, 43 Di g ital G round
RESET
25
Active-Low Reset Input/Output. Open-d ra in si gnal w ith internal pul lup r esistor to DV D D that remains low
until DV DD r ises above the brownout-reset (BOR) threshold and a ti meout per iod expi res. RESET is
pulled low by internal circuitry if DV D D falls below its brownout reset value. It can also be pul led low by
the internal watchdog timer, or externally by the user.
GATE5 24
D V D DIO Pass Transis tor Voltage Regulation Control. GATE5 connects d irectly to the gate of a depletion
mode trans istor or through level-shifting diodes to an enhancement mode or npn Dar l ington transistor that
supplies 5V to DV D DIO.
REG2P5 22
+2.5V Regulator Output. For self-powered operation, connect to DV D D and bypass to DGND with a 0.1µF
capacitor.
REG3P3 23
+3.3V Regulator Output. For self-powered operation, connect to AVD D and bypas s to AGND w ith a 0.1µF
capacitor.
(114 Seiten)
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Kommentare zu diesen Handbüchern