g696l463t Global Mixed-mode Technology Inc, g696l463t Datasheet - Page 7
g696l463t
Manufacturer Part Number
g696l463t
Description
Microprocessor Reset
Manufacturer
Global Mixed-mode Technology Inc
Datasheet
1.G696L463T.pdf
(8 pages)
Interfacing to µPs with Bidirectional Reset Pins
Since the RESET output on the G697L is open drain,
this device interfaces easily with µPs that have bidi-
rectional reset pins, such as the Motorola 68HC11.
Connecting the µP supervisor’s RESET output di-
rectly to the microcontroller’s (µC’s) RESET pin with
a single pull-up resistor allows either device to assert
reset (Figure 5).
G697L Open-Drain
Multiple Supplies
Generally, the pull-up connected to the G697L will
connect to the supply voltage that is being monitored
at the IC’s V
the open-drain output to level-shift from the monitored
supply to reset circuitry powered by some other supply
(Figure 6). Note that as the G697L’s V
below 1V, so does the IC’s ability to sink current at
Ver: 1.1
Jul 26, 2002
RESET . Also, with any pull-up, RESET will be pulled
CC
Global Mixed-mode Technology Inc.
pin. However, some systems may use
RESET
Output Allows Use with
CC
decreases
7
high as
occurs depends on the pull-up resistor value and the
voltage to which it is connected.
Benefits of Highly Accurate Reset Threshold
Most µP supervisor ICs have reset threshold voltages
between 5% and 10% below the value of nominal
supply voltages. This ensures a reset will not occur
within 5% of the nominal supply, but will occur when
the supply is 10% below nominal.
When using ICs rated at only the nominal supply ±5%,
this leaves a zone of uncertainty where the supply is
between 5% and 10% low, and where the reset may or
may not be asserted.
The G69_ _463/G69_ _308 use highly accurate circuitry
to ensure that reset is asserted close to the 5% limit,
and long before the supply has declined to 10% below
nominal.
VCC
decays toward 0. The voltage where this
G696/G697
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