CATALYST CAT811, CAT812 Service Manual

CAT811, CAT812

4-Pin Microprocessor Power Supply Supervisors with Manual Reset

FEATURES

 Precision monitoring of

+5.0 V (± 5%, ± 10%, ± 20%),
+3.3 V (± 5%, ± 10%),
+3.0 V (± 10%) and
+2.5 V (± 5%) power supplies

 Manual reset input
 Offered in two output configurations:
 CAT811: Active LOW reset
 CAT812: Active HIGH reset
 Direct replacements for the MAX811 and

MAX812 in applications operating over the
industrial temperature range

 Reset valid down to V

= 1.0V

CC

 6µA power supply current
 Power supply transient immunity
 Available in SOT-143 packages with Sn or

NiPdAu Green Lead finishes.

 Industrial temperature range: -40ºC to +85ºC

APPLICATION

 Computers, Servers, Laptops
 Cable modems
 Wireless communications
 Embedded control systems
 White goods
 Power meters
 Intelligent instruments
 PDAs and handheld equipment

DESCRIPTION

The CAT811 and CAT812 are microprocessor supervi­sory circuits that monitor power supplies. The CAT811
and CAT812 are direct replacements for the MAX811
and MAX812 in applications operating over the industrial
temperature range; both have a manual reset input.

These devices generate a reset signal, which is
asserted while the power supply voltage is below a
preset threshold level and for at least 140ms after the
power supply level has risen above that level. The
underlying floating gate technology, AE

2(TM)

used by
Catalyst Semiconductor, makes it possible to offer any
custom reset threshold value. Seven industry
standard threshold levels are offered to support
+5.0V, +3.3V, +3.0V and +2.5V systems.

The CAT811 features a RESET push-pull output
(active LOW) and the CAT812 features a RESET
push-pull output (active HIGH).

Fast transients on the power supply are ignored and
the output is guaranteed to be in the correct state at
Vcc levels as low as 1.0 V.

The CAT811/812 are fully specified over the industrial
temperature range (-40°C to 85°C) and are available
in a compact 4-pin SOT-143 package.

For Ordering Information details, see page 10.

THRESHOLD SUFFIX SELECTOR DESCRIPTION

Nominal Threshold

Voltage

4.63V L

4.38V M

Threshold Suffix

Designation

PIN CONFIGURATION

1

GND

CAT811
CAT812

¯¯¯¯¯¯

RESET

2 3

4 V

CC

¯¯¯

MR

4.00V J

3.08V T

2.93V S

2.63V R

2.32V Z

© Catalyst Semiconductor, Inc. 1 Doc. No. MD-3005 Rev. S
Characteristics subject to change without notice

CAT811, CAT812

V

V

PIN DESCRIPTION

Pin Number

CAT811 CAT812

Name Description

1 1 GND Ground

2 —

¯¯¯¯¯¯

RESET

Active LOW reset. RESET
and remains low for at least 140ms after V

¯¯¯¯¯¯

Active HIGH reset. RESET is asserted if V

— 2 RESET

and remains high for at least 140ms after V
threshold.

Manual Reset Input. A logic LOW on MR

3 3

¯¯¯

MR

active as long as MR
active low input has an internal 20k pull-up resistor. The input should be

¯¯¯

left open if not used.

4 4 V

Power supply voltage that is monitored.

CC

is asserted if V

is LOW and for 140ms after MR

falls below the reset threshold

CC

rises above the reset threshold.

CC

falls below the reset threshold

CC

rises above the reset

CC

¯¯¯

asserts RESET. RESET remains

¯¯¯

returns HIGH. The

BLOCK DIAGRAM

MR

CC

MR

CC

V

CC

TOLERANCE

BIAS

V

CC

TOLERANCE

BIAS

+

–

VOLTAGE

REFERENCE

+

–

GND

RESET

&

DIGITAL

DELAY

RESET

&

DIGITAL

DELAY

V

CC

CAT811

V

CC

RESET

RESET

VOLTAGE

REFERENCE

CAT812

GND

Doc. No. MD-3005 Rev. S 2 © Catalyst Semiconductor, Inc.

Characteristics subject to change without notice

CAT811, CAT812

ABSOLUTE MAXIMUM RATINGS

(1)

Parameters Ratings Units

Any pin with respect to ground -0.3 to + 6.0 V
Input Current, V
Output Current RESET, RESET
Rate of Raise, V

CC

¯¯¯¯¯¯

CC

Continuous Power Dissipations

20 mA
20 mA

100 V/µs

320 mW

Derate 4mW/ºC above +70ºC (SOT-143)
Storage Temperature -65 to +105 ºC
Operating Ambient Temperature -40 to +85 ºC
Lead Soldering (10 seconds) +300 ºC

ELECTRICAL OPERATING CHARACTERISTICS

VCC = Full range, TA = -40°C to +85°C unless otherwise noted. Typical values at TA = +25°C and VCC = 5V for the
L/M/J versions, V

Parameter Symbol Conditions Min Typ Max Units

VCC Range

Supply Current ICC TA = -40˚C to +85˚C

Reset

Threshold

Voltage

= 3.3V for the T/S versions, VCC = 3V for the R version and VCC = 2.5V for the Z version.

CC

TA = 0°C to +70°C 1.0 5.5
T

= -40°C to +85°C 1.2 5.5

A

VCC < 5.5V, J/L/M 8 20
V

< 3.6V, R/S/T/Z 6 15

CC

L Threshold

M Threshold

J Threshold

T Threshold

V

TH

S Threshold

R Threshold

Z Threshold

TA = +25°C 4.56 4.63 4.70
T

= -40°C to +85°C 4.50 4.75

A

TA = +25°C 4.31 4.38 4.45
T

= -40°C to +85°C 4.25 4.50

A

TA = +25°C 3.93 4.00 4.06
T

= -40°C to +85°C 3.89 4.10

A

TA = +25°C 3.04 3.08 3.11
T

= -40°C to +85°C 3.00 3.15

A

TA = +25°C 2.89 2.93 2.96
T

= -40°C to +85°C 2.85 3.00

A

TA = +25°C 2.59 2.63 2.66
T

= -40°C to +85°C 2.55 2.70

A

TA = +25°C 2.28 2.32 2.35
T

= -40°C to +85°C 2.25 2.38

A

V

µA

V

Notes:

(1) Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings

only, and functional operation of the device at these or any other conditions outside of those listed in the operational sections of this
specification is not implied. Exposure to any absolute maximum rating for extended periods may affect device performance and reliability.

© Catalyst Semiconductor, Inc. 3 Doc. No. MD-3005 Rev. S
Characteristics subject to change without notice

CAT811, CAT812

ELECTRICAL OPERATING CHARACTERISTICS (continued)

VCC = Full range, TA = -40°C to +85°C unless otherwise noted. Typical values at TA = +25°C and VCC = 5V for the
L/M/J versions, V

Parameter Symbol Conditions Min Typ
Reset Threshold

Tempco
VCC to Reset

(2)

Delay
Reset Active

Timeout Period

¯¯¯¯¯¯

RESET

Output
Voltage Low
(Push-pull, active
LOW, CAT811)

¯¯¯¯¯¯

RESET

Output
Voltage High
(Push-pull, active
LOW, CAT811)

RESET Output
Voltage Low
(Push-pull, active
HIGH, CAT812)

RESET Output
Voltage High
(Push-pull active
HIGH, CAT812)

¯¯¯

MR

Minimum

Pulse Width
¯¯¯

MR

Glitch

Immunity
¯¯¯

MR

to RESET

Propagation Delay

¯¯¯

MR

Input

Threshold

= 3.3V for the T/S versions, VCC = 3V for the R version and VCC = 2.5V for the Z version.

CC

(1)

Max Units

30 ppm/˚C

V

T

V

OL

V

OH

V

OL

V

OH

10 µs

t

MR

= VTH to (VTH - 100mV) 20 µs

CC

= -40˚C to +85˚C 140 240 400 ms

A

VCC = V
CAT811R/S/T/Z

VCC = V
CAT811J/L/M

> 1.0V, I

V

CC

VCC = V
CAT811R/S/T/Z

V

= V

CC

CAT811J/L/M
VCC > V

CAT812R/S/T/Z
V

> V

CC

CAT812J/L/M

1.8 V < V
I

SOURCE

, I

TH min

SINK

, I

TH min

SINK

SINK

, I

TH max

TH max

TH max

TH max

CC

, I

, I

, I

 V

SOURCE

SOURCE

SINK

SINK

TH min

= 150µA

= 1.2mA

= 3.2mA

0.3

0.4

= 50µA 0.3

= 500µA

= 800µA

= 1.2mA

= 3.2mA

,

0.8V

V

0.8V

CC

- 1.5

CC

0.3

0.4

V

CC

Note 3 100 ns

Note 2 0.5 µs

t

MD

V

VCC > V

IH

V

0.8 V

IL

V

VCC > V

IH

, CAT811/812L/M/J 2.3V

TH (MAX)

, CAT811/812R/S/T/Z 0.7VCC

IH (MAX)

V

V

V

V

0.25V

IL

¯¯¯

MR

Pull-up

Resistance

Notes:

(1) Production testing done at T

¯¯¯¯¯¯

(2) RESET
(3) Glitches of 100ns or less typically will not generate a reset pulse

Doc. No. MD-3005 Rev. S 4 © Catalyst Semiconductor, Inc.

output for the CAT811; RESET output for the CAT812

10 20 30 k

= +25˚C; limits over temperature guaranteed by design only.

A

Characteristics subject to change without notice

CC