MAX6329 Maxim, MAX6329 Datasheet - Page 6

• Manufacturer Part Number: MAX6329
• Description: 150mA / SOT23 / Low-Dropout Linear Regulators with Internal Microprocessor Reset Circuit
• Manufacturer: Maxim

150mA, SOT23, Low Dropout Linear Regulators
with Internal Microprocessor Reset Circuit
The MAX6329/MAX6349 are low-dropout, low-quies-
cent current linear regulators with integrated micro-
processor reset circuits. The devices drive loads up to
150mA and are available with preset output voltages of
+3.3V, +2.5V, or +1.8V. The internal reset circuit moni-
tors the regulator output voltage and asserts the reset
output when the regulator output is below the micro-
processor supply tolerance.
The regulator core operates with an input voltage range
of +2.5V to +5.5V. The output voltage is offered with
three fixed voltage options (+3.3V, +2.5V, and +1.8V) for
the MAX6329 and MAX6349. Enable the fixed voltage
output
MAX6329/MAX6349 offer an adjustable output voltage
that is implemented with an external resistor-divider net-
work connected to OUT, SET, and GND (Figure 1). SET
must be connected to either GND or the external divider.
The MAX6329/MAX6349 automatically determine the
feedback path depending on the voltage seen at SET.
Featured characteristics include ultra-low quiescent cur-
rent and low dropout voltage. The Typical Operating
Circuit shows a typical connection for the MAX6329.
6
_______________________________________________________________________________________
PIN
1
2
3
4
5
6
by
RESET
RESET
NAME
SHDN
connecting
GND
OUT
SET
MR
IN
Detailed Description
Regulator Input. Supply voltage can range from +2.5V to +5.5V.
Ground. This pin also functions as a heatsink. Solder to large pads or the circuit board ground plane to
maximize thermal dissipation.
(MAX6329 Only) Active-Low Shutdown Input. A logic low reduces the supply current to < 1µA. Connect
(MAX6349 Only) Active-Low Manual Reset Input. A logic low forces a reset. Reset remains asserted for
the duration of the reset timeout period after MR transitions from low to high. Leave unconnected or
connect to V
Active-Low Reset Output. RESET remains low while V
held low. RESET remains low for the duration of the reset timeout period after the reset conditions are
terminated.
Active-High Reset Output. RESET remains high while V
held low. RESET remains high for the duration of the reset timeout period after the reset conditions are
terminated.
Feedback Input for Setting the Output Voltage. Connect to GND to set the output voltage to the preset
fixed value (+3.3V, +2.5V, or +1.8V). Connect to an external resistor-divider network for adjustable
output operation.
Regulator Output. Fixed (+3.3V, +2.5V, or +1.8V) or adjustable (+1.23V to +5.0V). Sources up to
150mA. Bypass with a 1µF minimum capacitor for full rated performance.
SET
OUT
to
if not used. MR has an internal pullup resistor of 20kΩ (typ) to OUT.
ground.
Regulator
The
OUT is an internally regulated low dropout (LDO) linear
regulator that powers a microprocessor.
The reset supervisor circuit is fully integrated in the
MAX6329/MAX6349 and uses the same reference volt-
age as the regulator. Two supply tolerance reset thresh-
olds, -5% and -10%, are provided for each type of
device:
Figure 1. Adjustable Output Voltage Configuration
DESCRIPTION
OUT
2.5V TO 5.5V
OUT
is below the reset threshold or while MR is
is below the reset threshold or while MR is
MAX6329
MAX6349
GND
IN
OUT
SET
Pin Description
Reset Circuit
R1
R2