MAX6766 MAXIM [Maxim Integrated Products], MAX6766 Datasheet - Page 15

no-image

MAX6766

Manufacturer Part Number
MAX6766
Description
Automotive Micropower Linear Regulators with Supervisor
Manufacturer
MAXIM [Maxim Integrated Products]
Datasheet
The regulator accepts an input voltage from +4V to +72V.
All of the devices feature fixed output-voltage options of
+1.8V, +2.5V, +3.3V, and +5V. The MAX6767–MAX6774
feature an adjustable output voltage set with an external
resistive-divider network connected between OUT, SET,
and GND. See Figure 1.
The MAX6767/MAX6768 support two logic inputs,
ENABLE (active-high) and HOLD (active-low), making
these devices “automotive friendly.” For example, when
the ignition key signal drives ENABLE high, the regulator
turns on and remains on even if ENABLE goes low, as
long as HOLD is forced low and kept low before
ENABLE goes low. In this state, releasing HOLD turns
the regulator output (OUT) off. This feature makes it pos-
sible to implement a self-holding circuit without external
components. Forcing ENABLE low with HOLD high (or
unconnected) places the MAX6767/MAX6768 into shut-
down mode, drawing 3.3µA (typ) of supply current.
Table 3 shows the state of the regulator output with
respect to the voltage level at ENABLE and HOLD.
Connect HOLD to OUT or leave it unconnected to allow
the ENABLE input to act as a standard enable/shut-
down switch for the regulator output (OUT).
The reset output is typically connected to the reset
input of a µP. A µP’s reset input starts or restarts the µP
in a known state. The MAX6765–MAX6774 supervisory
circuits provide the reset logic to prevent code-execu-
tion errors during power-up, power-down, and
brownout conditions (see the Typical Application
Circuit). RESET changes from high to low whenever the
monitored voltage drops below the reset threshold volt-
ages. Once the monitored voltage exceeds its respec-
tive reset threshold voltage(s), RESET remains low for
the reset timeout period, then goes high. See Table 1.
The MAX6769/MAX6770 monitor the voltage on RESETIN
using an adjustable reset threshold (V
an external resistive voltage-divider and the internal reset
threshold V
RESETIN Threshold (MAX6769/MAX6770)
TH
. See Table 2.
Automotive Micropower Linear Regulators
______________________________________________________________________________________
Enable and Hold Inputs
(MAX6767/MAX6768)
Reset Output
RESETIN
Regulator
) set with
Figure 1. Setting the Output Voltage Using a Resistive Divider
Table 1. Preset Timeout Period
Table 2. Preset Output Voltage and Reset
Threshold
PART NUMBER
SUFFIX (_)
PART NUMBER
M
W
L
T
S
Z
Y
V
SUFFIX (_)
D0
D1
D2
D3
D4
with Supervisor
MAX6767–MAX6774
VOLTAGE (V)
OUTPUT
GND
V
IN
IN
3.3
3.3
2.5
2.5
1.8
1.8
5
5
OUT
SET
TIMEOUT
PERIOD
3.125ms
12.5ms
R1
R2
200ms
THREHOLD (V)
50ms
75µs
RESET
4.625
4.375
3.053
2.888
2.313
2.188
1.665
1.575
15

Related parts for MAX6766