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19-4779; Rev 0; 8/98
Supervisory Circuit Evaluation Kit
General Description
Maxim’s line of supervisory circuits offers multiple wafer
trimmable options, leading to thousands of variations.
The large number of variations makes it difficult to offer
samples for each unique version. The Supervisory
Circuit Evaluation Kit (SUPEVKIT) has been developed
to emulate all the different variations of the MAX63XX
line. It reproduces the logic of this line but not the elec-
trical characteristics. Any device in these product fami-
lies can be emulated simply by changing jumper
settings and using a capacitor, if required.
The SUPEVKIT supports the following MAX63XX devices:
MAX6305
MAX6306
MAX6307
MAX6308
MAX6309
MAX6310
MAX6311
MAX6312
MAX6313
MAX6314
MAX6315
MAX6316L
MAX6316M
MAX6317H
MAX6318LH
MAX6318MH
MAX6319LH
MAX6319MH
MAX6320P
MAX6321HP
MAX6322HP
MAX6326
MAX6327
MAX6328
MAX6332*
MAX6333*
MAX6334*
MAX6335*
MAX6336*
MAX6337*
PART
SUPEVKIT
Features
o
Easy to Configure
o
Five Reset Outputs
Bidirectional
RESET
Open-Drain
RESET
Push/Pull
RESET
Push/Pull RESET
Open-Drain RESET
o
Adjustable Reset Timeout
o
Manual Reset Input
o
Adjustable Under/Overvoltage Supply Monitoring
o
Adjustable Watchdog Timeout
o
Reset Valid Down to V
CC
= 1V
o
Immune to Short Negative-Going V
CC
Transients
o
Assembled and Tested
SUPEVKIT
Ordering Information
TEMPERATURE
+25°C
*Future
product—contact factory for availability.
Component Suppliers
SUPPLIER
Central
Semiconductor
Taiyo Yuden
PHONE
515-435-1110
408-573-4150
FAX
515-435-1824
408-573-4159
Component List
DESIGNATION QTY
C1
C2
C3, C4
C5
C6
C7
JU1, JU2
JU3, JU4, JU5
R1, R8
R2, R9
1
0
0
1
1
1
2
3
2
2
DESCRIPTION
470pF, ±20% ceramic capacitor
Not installed (user supplied)
Not installed (user supplied)
0.01µF, ±20% ceramic capacitor
0.068µF, ±20% ceramic capacitor
0.47µF, ±10% ceramic capacitor
Taiyo Yuden TMK316BJ474KL
3-pin jumpers
2-pin jumpers
30kΩ, 5% resistors
39kΩ, 5% resistors
DESIGNATION QTY
R3, R4, R5,
R10, R13, R16
R6, R7
R11, R12,
R14, R15, R17
R18, R19
Q1
Q2–Q5
U1
U2
U3
6
2
5
2
1
4
1
1
1
DESCRIPTION
10kΩ, 5% resistors
1MΩ, 5% resistors
100kΩ, 5% resistors
100kΩ trimmer potentiometers
2N3906 PNP transistor
Central Semiconductor CMPT3906
2N3904 NPN transistors
Central Semiconductor CMPT3904
MAX969EEE
MAX6303CUA
MAX6314US26D1-T
1
________________________________________________________________
Maxim Integrated Products
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Supervisory Circuit Evaluation Kit
SUPEVKIT
Quick Start
Before you begin, you will need the following equip-
ment:
to 0. The reset threshold voltage on the SUPEVKIT
is now set.
8) Connect the SUPEVKIT to the test circuit, using the
device inputs and outputs listed in Table 1.
Example: The MAX6320PUK33BX-T uses pads
MR,
WDI, and
RESETOD.
•
A 1V to 5.5V variable DC power supply
•
A voltmeter
•
A trimmer potentiometer adjustment tool (small
flat-blade screwdriver)
Table 1 lists the features that can be emulated by the
SUPEVKIT. Refer to the corresponding device’s data
sheet to look up the specifications for these features.
To configure the supervisory circuit, take the following
steps:
1) Install jumpers JU2–JU5 in the positions listed in
Table 1.
Example: For the MAX6320PUK33BX-T, the jumper
settings are JU2 = 2-3, JU3 = open, JU4 = closed,
and JU5 = closed.
2) Set the reset timeout period, referring to Table 2 to
determine which trace (if any) needs to be cut.
Example: For the MAX6320PUK33BX-T, the reset
timeout period is 20ms, so it is necessary to cut the
trace between C5 and C6.
3) If the selected supervisory circuit has a watchdog
timeout feature, consult Table 3 to determine which
capacitor value to use for C2 and which position to
use for jumper JU1.
Example: For the MAX6320PUK33BX-T, the watch-
dog timeout period is 71ms. Use a value of 0.039µF
for capacitor C2. Jumper JU1 should be in the 2-3
position.
4) Turn on the power supply and connect it to the volt-
meter. Set the power-supply voltage to the desired
reset threshold voltage. The accuracy of the trip
threshold is determined by the accuracy of the volt-
meter.
Example: For the MAX6320PUK33BX-T, set the
power supply to 3.30V.
5) Connect the power supply to the SUPEVKIT at the
pads labeled V
CC
and GND. The SUPEVKIT oper-
ates from +1V to +5.5V.
The supply voltage must
not exceed +5.5V.
6) Connect the voltmeter to the pads labeled TP and
GND.
7) Turn potentiometer R18 clockwise until the volt-
meter reading goes high (approximately equal to
V
CC
). Then slowly turn potentiometer R18 counter-
clockwise until the voltmeter reading decreases
2
Detailed Description
Watchdog Circuit
A watchdog circuit consists of an input (WDI) and an
output (RESET). If WDI is not toggled within the watch-
dog timeout period (which is a predetermined amount
of time), then a RESET is issued. Disable the watchdog
function by installing jumper JU3.
Capacitor C2 selects the watchdog timeout period. To
choose a value for this capacitor, refer to Table 3 or use
the following formula:
C2 = t
WD
/ 2.67
where t
WD
is the watchdog timeout period in µs and C2
is in pF.
The SUPEVKIT features two modes of watchdog timer
operation: normal mode and extended mode. In normal
mode (JU1 = 2-3), the formula shown above deter-
mines the watchdog timeout period. In extended mode
(JU1 = 1-2), the watchdog timeout (t
WD
) is multiplied by
a factor of 500.
Note:
In extended mode operation, leaving pad WDI
floating disables the watchdog feature.
Reset Outputs
The SUPEVKIT has five reset outputs: active-low
push/pull (RESET), active-low bidirectional (RESETBD),
active-low open-drain (RESETOD), active-high push/pull
(RESET), and active-high open-drain (RESETOD).
These outputs are valid down to V
CC
= 1V. The reset
timeout period is the amount of time RESET is asserted
after V
CC
rises above the reset threshold voltage.
Capacitors C1, C5, C6, and C7 set the reset timeout
period. The SUPEVKIT comes with the period set at
1120ms. To change the period to either 1ms, 20ms, or
140ms, cut a PC board trace as specified in Table 2.
The bidirectional reset output of the SUPEVKIT is valid
only for reset threshold voltages down to 2.63V.
Undervoltage Setup
Potentiometer R18 sets the undervoltage reset thresh-
old. To enable the undervoltage reset feature, install the
jumpers in the positions specified in Table 4. Use a volt-
meter to set the power-supply voltage to the desired trip
_______________________________________________________________________________________
Supervisory Circuit Evaluation Kit
SUPEVKIT
Table 1. Devices and Settings
DEVICE INPUTS
OVERSTIN
RSTIN1
RSTIN2
DEVICE
DEVICE OUTPUTS
RESETOD
RESETOD
RESETBD
INSTALL
ADJUST
RESET
RESET
USER SETTINGS
WDI
JU2
JU4
MAX6305
MAX6306
MAX6307
MAX6308
MAX6309
MAX6310
MAX6311
MAX6312
MAX6313
MAX6314
MAX6315
MAX6316L
MAX6316M
MAX6317H
MAX6318LH
MAX6318MH
MAX6319LH
MAX6319MH
MAX6320P
MAX6321HP
MAX6322HP
MAX6326
MAX6327
MAX6328
MAX6332
MAX6333
MAX6334
MAX6335
MAX6336
MAX6337
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
R18
R18
R18
R18
R18
R18
X
X
C2
X
C2
C2
C2
X
X
X
X
X
C2
C2
C2
R18
R18
R18
R18
R18
R18
R18
R18
R18
R18
R18
R18
R18
R18
X
X
X
X
X
X
X
X
X
X
R18
R18
R18
R18
R18
R18
R18
2-3
2-3
open
2-3
2-3
open
2-3
2-3
open
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
open
open
open
open
open
closed
closed
open
open
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
JU3
open
closed
closed
open
closed
closed
open
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
open
open
open
open
open
open
open
open
open
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
closed
X
X
X
X
X
X
X
X
Note:
All devices require V
CC
and GND connections.
_______________________________________________________________________________________
JU5
3
MR
Supervisory Circuit Evaluation Kit
SUPEVKIT
voltage. Connect a voltmeter or oscilloscope to the TP
pad. Turn R18 clockwise until the voltage at TP goes
high (V
CC
). Slowly turn R18 counterclockwise until the
voltage goes low. The SUPEVKIT is now set to trip when
the supply voltage decreases to this voltage. To disable
undervoltage reset, open jumper JU4.
Table 4. Undervoltage Setup
JUMPER
JU2
JU3
JU4
JU5
STATE
2-3
Closed
Closed
Closed
Overvoltage Setup
Potentiometer R19 sets the overvoltage reset threshold.
To enable the overvoltage reset feature, install the
jumpers in the positions specified in Table 5. Use a volt-
meter to set the power-supply voltage to the desired trip
voltage. Connect a voltmeter or oscilloscope to the TP
pad. Turn R19 clockwise until the voltage at TP goes
high (V
CC
). Slowly turn R19 counterclockwise until the
voltage goes low. The SUPEVKIT is now set to trip when
the supply voltage increases to this voltage. To disable
overvoltage reset, move JU2’s shunt to position 2-3.
Note: If the voltage at TP does not pull high after turning
R19 clockwise for 14 turns, turn R18 counterclockwise.
The undervoltage trip point might be set higher than the
supply voltage, holding the SUPEVKIT in reset.
Table 5. Overvoltage Setup
JUMPER
JU2
JU3
JU4
JU5
STATE
1-2
Closed
Closed
Closed
Table 6. Jumper Function Table
JUMPER
STATE
1-2
JU1
2-3*
FUNCTION
Watchdog-select connected to V
CC
(extended mode).
Watchdog-select connected to GND
(normal mode).
Use R19 to set overvoltage threshold.
Disable overvoltage comparator.
Use OVRSTIN pad.
Use watchdog function (insert C2).
Disable watchdog function.
Use RSTIN1 pad.
Use R18 to set undervoltage threshold.
Use RSTIN2 pad.
Disable RSTIN2 undervoltage
comparator.
Negative-Going V
CC
Transients
The SUPEVKIT is relatively immune to short-duration
negative-going transients (glitches). If more immunity is
required, install 0.1µF bypass capacitors for C3 and C4.
Table 2. Selecting the Reset Timeout
Period
MINIMUM
TIMEOUT PERIOD (ms)
1
20
140
1120
*Default
jumper state.
CUT TRACE
BETWEEN:
C1 and C5
C5 and C6
C6 and C7
No cutting necessary*
1-2
JU2
2-3*
Open
JU3
JU4
Open
Closed*
Open
Closed*
Open
JU5
Closed*
*Default
jumper state.
Table 3. Capacitance Values for
Common Watchdog Timeout Periods
MINIMUM
WATCHDOG
TIMEOUT (t
WD
)
4.3ms
71ms
1.12sec
17.9sec
4
C1 VALUE
2200pF ±20%
0.039µF ±20%
1200pF ±20%
0.018µF ±20%
JU1 STATE
2-3
2-3
1-2
1-2
_______________________________________________________________________________________
Supervisory Circuit Evaluation Kit
SUPEVKIT
Pad Description
PAD NAME
V
CC
GND
WDI
RSTIN1
RSTIN2
OVRSTIN
MR
RESET
RESETOD
DESCRIPTION
Supply Voltage and Reset Threshold Monitor Input (1V to 5.5V)
Ground
Watchdog Input. A rising or falling transition must occur on this input within the selected watchdog timeout period, or a
reset will occur.
Undervoltage Reset Comparator Input. Asserts reset when the monitored voltage falls below the programmed thresh-
old. Set the reset threshold with an external resistor-divider.
Undervoltage Reset Comparator Input. Asserts reset when the monitored voltage falls below the programmed
threshold. Set the reset threshold with an external resistor-divider.
Overvoltage Reset Comparator Input. Asserts reset when the monitored voltage exceeds the programmed thresh-
old. Set the reset threshold with an external resistor-divider.
Manual Reset Input. A logic low on
MR
asserts reset. Reset remains asserted as long as
MR
is low, and for the
duration of the reset timeout period (t
RP
) after the reset condition is terminated.
Push/Pull, Active-High Reset Output. RESET changes from low to high whenever a reset condition occurs. After the
reset condition is terminated, RESET remains high for the duration of the reset timeout period and then goes low.
Open-Drain, Active-High Reset Output. RESETOD is asserted high whenever a reset condition occurs. After the reset
condition is terminated, RESETOD remains high for the duration of the reset timeout period.
Push/Pull, Active-Low Reset Output.
RESET
changes from high to low whenever a reset condition occurs.
RESET
remains low for the duration of the reset timeout period. After the reset condition is terminated,
RESET
remains low
for the duration of the timeout period and then goes high.
Open-Drain, Active-Low Reset Output.
RESETOD
is asserted low whenever a reset condition occurs. After the reset
condition is terminated,
RESETOD
remains low for the duration of the reset timeout period.
Bidirectional, Active-Low Reset Output.
RESETBD
changes from high to low whenever a reset condition occurs.
After the reset condition is terminated,
RESETBD
remains low for the duration of the reset timeout period and then
goes high. In addition to the normal N-channel pull-down,
RESETBD
has a P-channel pull-up transistor in parallel
with a 4.7kΩ resistor to facilitate connection to µPs with bidirectional resets. See the MAX6314 data sheet.
RESET
RESETOD
RESETBD
_______________________________________________________________________________________
5

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