MAX811SEUS+T Maxim Integrated Products, MAX811SEUS+T Datasheet - Page 6

• Manufacturer Part Number: MAX811SEUS+T
• Description: IC MPU V-MONITOR 2.93V SOT143-4
• Manufacturer: Maxim Integrated Products
• Type: Simple Reset/Power-On Resetr

Specifications of MAX811SEUS+T

• Number Of Voltages Monitored: 1
• Output: Push-Pull, Totem Pole
• Reset: Active Low
• Reset Timeout: 140 ms Minimum
• Voltage - Threshold: 2.93V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: SOT-143, SOT-143B, TO-253AA
• Monitored Voltage: 3 V or 3.3 V or 5 V
• Undervoltage Threshold: 2.88 V
• Overvoltage Threshold: 2.98 V
• Manual Reset: Resettable
• Watchdog: No
• Battery Backup Switching: No
• Power-up Reset Delay (typ): 560 ms
• Supply Voltage (min): 1.2 V
• Supply Current (typ): 2.7 uA (Typ)
• Maximum Power Dissipation: 320 mW
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 85 C
• Chip Enable Signals: No
• Minimum Operating Temperature: - 40 C
• Output Type: Active Low or Push-Pull
• Power Fail Detection: No
• Dc: 06+
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MAX811SEUS+TTR

__________ Applications Information
In addition to issuing a reset to the µP during power-up,
power-down, and brownout conditions, the MAX811/
MAX812 are relatively immune to short duration nega-
tive-going V
Figure 1 shows typical transient durations vs. reset
comparator overdrive, for which the MAX811/MAX812
do not generate a reset pulse. This graph was generat-
ed using a negative-going pulse applied to V
ing above the actual reset threshold and ending below
it by the magnitude indicated (reset comparator over-
drive). The graph indicates the typical maximum pulse
width a negative-going V
causing a reset pulse to be issued. As the magnitude
of the transient increases (goes farther below the reset
threshold), the maximum allowable pulse width
decreases. Typically, a V
below the reset threshold and lasts 40µs or less
(MAX81_L/M) or 20µs or less (MAX81_T/S/R) will not
cause a reset pulse to be issued. A 0.1µF capacitor
mounted as close as possible to V
tional transient immunity.
4-Pin µP Voltage Monitors
with Manual Reset Input
Figure 1. Maximum Transient Duration without Causing a
Reset Pulse vs. Comparator Overdrive
6
_______________________________________________________________________________________
CC
8
7
6
5
4
3
2
1
0
RESET COMPARATOR OVERDRIVE , V
Negative-Going V
transients (glitches).
1
T
MAX81 _L/M
A
= +25°C
MAX81 _R/S/T
10
CC
CC
transient may have without
transient that goes 125mV
100
CC
TH
CC
- V
provides addi-
CC
Transients
(mV)
1000
CC
, start-
When V
no longer sinks current—it becomes an open circuit.
Therefore, high-impedance CMOS-logic inputs con-
nected to the RESET output can drift to undetermined
voltages. This presents no problem in most applica-
tions, since most µP and other circuitry is inoperative
with V
RESET output must be valid down to 0V, adding a pull-
down resistor to the RESET pin will cause any stray
leakage currents to flow to ground, holding RESET low
(Figure 2). R1’s value is not critical; 100kΩ is large
enough not to load RESET and small enough to pull
RESET to ground.
A 100kΩ pull-up resistor to V
for the MAX812 if RESET is required to remain valid for
V
Figure 2. RESET Valid to V
CC
< 1V.
CC
CC
below 1V. However, in applications where the
falls below 1V, the MAX811 RESET output
Ensuring a Valid RESET Output
MAX811
GND
V
CC
CC
RESET
= Ground Circuit
CC
Down to V
is also recommended
R1
CC
= 0V