19-2531; Rev 2; 12/05
Low-Power Dual-/Triple-Voltage SC70 µP
Supervisory Circuits
General Description
The MAX6736–MAX6745 are low-power dual-/triple-
voltage microprocessor (µP) supervisors. These
devices assert a reset if any monitored supply falls
below its factory-trimmed or adjustable threshold and
maintain reset for a minimum timeout period after all
supplies rise above their thresholds. The integrated
dual/triple supervisory circuits significantly reduce size
and power compared to separate ICs or discrete com-
ponents. The low supply current of 6µA makes these
devices ideal for portable equipment.
The MAX6736/MAX6737 are dual fixed-voltage µP
supervisors with a manual reset input. The MAX6738/
MAX6739 have one fixed and one adjustable reset
threshold and a manual reset input. The MAX6740/
MAX6743 are triple-voltage µP supervisors with two
fixed and one user-adjustable reset threshold inputs.
The MAX6741/MAX6744 are dual-voltage µP supervi-
sors with a power-OK (POK) output ideal for power-
supply sequencing. The MAX6742/MAX6745 monitor
the primary VCC supply and have an independent
power-fail comparator.
The MAX6736–MAX6745 monitor I/O supply voltages
(VCC1) from 1.8V to 5.0V and core supply voltages
(VCC2) from 0.9V to 3.3V with factory-trimmed reset
threshold voltage options (Table 1). An external
adjustable RSTIN input option allows monitoring volt-
ages down to 0.5V.
A variety of push-pull or open-drain reset outputs along
with manual reset input and power-fail input/output fea-
tures are available (see the Selector Guide). The
MAX6736–MAX6745 are offered in a space-saving 5-pin
SC70 package and operate over the -40°C to +85°C
temperature range.
Applications
Portable/Battery-
Powered Equipment
Multivoltage Systems
Notebook Computers
Controllers
PDAs
GPS Equipment
POS Equipment
Features
♦ Dual-/Triple-Supply Reset Voltage Monitors
♦ Precision Factory-Set Reset Thresholds for
Monitoring from 0.9V to 5.0V
♦ Adjustable Reset Input Down to 0.488V
♦ 150ms and 1200ms (min) Reset Timeout Period
Options
♦ VCC1 Power-OK Output for Power-Supply
Sequencing Applications (MAX6741/MAX6744)
♦ Power-Fail Input/Power-Fail Output
(MAX6742/MAX6745)
♦ 6µA Supply Current
♦ Tiny SC70 Package
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX6736XK_ _D_-T -40°C to +85°C 5 SC70-5
MAX6737XK_ _D_-T -40°C to +85°C 5 SC70-5
Note: The first “_ _” or “_” are placeholders for the threshold
voltage levels of the devices. Desired threshold levels are set
by the part number suffix found in Tables 1 and 2. The “_” after
the D is a placeholder for the reset timeout period suffix found
in Table 3. For example, the MAX6736XKLTD3-T is a dual-volt-
age supervisor VTH1 = 4.625V, VTH2 = 3.075V, and a 150ms
minimum reset timeout period. All devices are available in
tape-and-reel only. There is a 2500-piece minimum order
increment for standard versions (see Table 1). Sample stock is
typically held on standard versions only. Nonstandard versions
require a minimum order increment of 10,000 pieces. Contact
factory for availability.
Devices are available in both leaded and lead-free packaging.
Specify lead-free by replacing “-T” with “+T” when ordering.
Ordering Information and Selector Guide continued at end
of data sheet.
Pin Configurations, Typical Application Circuits, and
Functional Diagram appear at end of data sheet.
Selector Guide
PART
VOLTAGE
MONITORS
OPEN-DRAIN PUSH-PULL
RESET
RESET
MANUAL
RESET
POWER-FAIL
INPUT/
OUTPUT
POK
OUTPUT
RSTIN
INPUT
MAX6736
2 fixed
MAX6737
2 fixed
MAX6738
1 fixed, 1 adj
*Manual reset detect on RESET output.
X
—
X
—X
XX
—X
— ——
— ——
— —X
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
