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CAT885
Five-Channel Power Supply Supervisors
FEATURES
Five-channel supply voltage detection 2 VDD inputs allow monitoring of +5.0V, +3.3V, +3.0V, +2.5V or +1.8V supplies 3 adjustable voltage inputs allow monitoring supplies > 0.6V 70ms minimum reset delay Manual reset capability Reset signals valid down to VDD = 1V Accurate < 2% voltage threshold Power-supply transients suppressed Low 2A maximum supply current at 5V RoHS-compliant MSOP package
DESCRIPTION
The CAT885 is a five-channel power supply supervisory circuit with high reset thereshold accuracy and very low power consumption. The device features an open-drain output, active-low function with manual reset to perform basic system reset and monitoring functions for a wide range of electronic products. The CAT885 monitors five system voltages by maintaining a reset output active until all the power supply voltages exceed the specified trip values. The device then maintains the reset output in an active condition until the internal timer times out, which allows the system power supplies to stabilize. Two of the five voltage detectors are factory set for standard supplies, while the threshold voltages of the third, fourth, and fifth voltage monitors can be adjusted for specific system design requirements using external resistors. The CAT885 lowers system costs and saves board space by integrating five channels into a single, small MSOP 8-lead package. For Ordering Information details see page 7.
APPLICATIONS
Telecom & datacom systems Routers & servers Data storage equipment Set-top boxes Multi-voltage systems
PIN CONFIGURATION
MSOP 8-Lead (Z)
(top view) MR VDD VDD2 VSS 1 2 3 4 CAT885 8 RST 7 V5MON 6 V4MON 5 V3MON
TYPICAL APPLICATION
VDD VDD2 V3MON CAT885 V4MON MR RST Reset Signal
See page 2 for pin functions
V5MON
PB VSS
(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice
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Doc. No. MD-3028 Rev. C
CAT885 FUNCTIONAL BLOCK DIAGRAM
VDD VDD POR VREF VDD2 VDD RST VREF V3MON 120 ms TIME-OUT V4MON Reset Signal MR PB
VREF
VREF V5MON
VSS VREF
PIN FUNCTIONS
Pin # 1 2 3 4 5 6 7 8 Pin MR VDD VDD2 VSS V3MON V4MON V5MON RST Function Active-low manual reset Input with internal pull-up resistor Chip supply, first preset under-voltage detector input Second preset under-voltage detector input Ground Adjustable third under-voltage detector input Adjustable fourth under-voltage detector input Adjustable fifth under-voltage detector input Active-low open drain reset output, use external resistor
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(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice
CAT885 ABSOLUTE MAXIMUM RATINGS (1)
Parameters Temperature under Bias Voltage on any Pin with Respect to VSS DC Output Current Thermal Resistance JA for MSOP Package
(2)
Ratings -40 to +125 -1.0 to +7.0 5 145
Units C V mA C/W
RECOMMENDED OPERATING CONDITIONS
Parameters Operating Temperature Range (Industrial) Storage Temperature Lead Soldering Temperature (10 seconds) Ratings -40 to +85 -65 to +150 +300 Units C C C
ELECTRICAL CHARACTERISTICS
Over the recommended operating conditions unless otherwise specified. Symbol VDD IDD1 IDD2 IDDX VTH1 VTH1HYST Parameter Supply Voltage Range VDD Supply Current VDD2 Input Current V3, V4, V5MON Input Current Fixed Voltage Trip Point for VDD Hysteresis of VTH1 Conditions VDD = 5.0V VDD2 = 3.3V V3, V4, V5MON = 1.0V CAT885Lx CAT885Sx VTH1 = 4.63V VTH1 = 2.87V CAT885xT CAT885xS CAT885xZ CAT885xA VTH2 = 3.08V VTH2 = 2.95V VTH2 = 2.33V VTH2 = 1.68V VTH for V3, V4, V5MON 4.55 2.81 Min 1.5 Typ. 2 0.5 15 4.63 2.87 50 30 3.08 2.95 2.33 1.68 40 30 25 20 0.598 3 Max 5.5 9 3 50 4.72 2.92 Units V A A nA V V mV mV V V V V mV mV mV mV V mV
Voltage Thresholds
VTH2
Fixed Voltage Trip Point for VDD2
3.02 2.90 2.29 1.65
3.13 3.01 2.37 1.71
VTH2HYST
Hysteresis of VTH2 V3MON, V4MON, V5MON Adj. Reset Threshold Voltage Hysteresis Voltage
VREF VREFHYST
0.585
0.611
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 devices 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. (2) JA is measured with the component mounted on a high effective thermal conductivity test board in free air. 3
Doc. No. MD-3028 Rev. C
(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice
CAT885
ELECTRICAL CHARACTERISTICS (continued) Symbol Reset VOL tRPD tPD CLOAD Reset Output Voltage Low VTH to Reset Asserted Delay POR Timeout Delay Load Capacitance on Reset Pin VDD 3.3V, Sinking 2.5mA VDD < 3.3V, Sinking 1.5mA 1 70 0.05 0.05 6 120 5 0.40 0.40 240 V V s ms pF V V s k Parameter Conditions Min Typ. Max Units
Manual Reset Input Voltage Low VTHL MR Input Voltage High VTHH MR Minimum Pulse Width TPW MR RIN Internal Pull-Up Resistor
0.8 VDD - 0.6 1 8
16
OPERATION
The CAT885 is designed to monitor critical supply voltages in line driven and battery powered microprocessor systems, providing Supply Voltage Supervision, Power On Reset control and Manual Reset Assertion. These features along with excellent threshold accuracy and low power consumption make the CAT885 device suitable for a wide variety of applications needing multi-voltage monitoring. During normal operation, the CAT885 monitors the voltage levels of VDD, V2MON, V3MON, V4MON, and V5MON. If the voltage on any of these five inputs falls below their respective voltage trip points, a reset is asserted (RST = low) to prevent the microprocessor from operating during a power failure or brownout condition. This reset signal remains low until the voltages exceeds the voltage threshold settings for the reset time delay period tPD. CAT885 allows users to adjust the minimum voltage sense level for three of the five monitored voltages. For example, the user can adjust the voltage input trip point for V3MON, V4MON and V5MON inputs. This is done by connecting an external resistor divider network to the VxMON pin in order to set the trip point to a voltage above 600mV. Resistors R1 and R2 in Figure 1 are selected by the formula: VTRIP = 0.6V x (R1 + R2) / R2.
VDD V2MON CAT885 R1 VxMON R2 GND
Figure 1. CAT885 Programming Trip Voltage
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(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice
CAT885
POWER ON RESET (POR) Applying power to the CAT885 activates a POR circuit which activates the reset output (active LOW). At power-up POR prevents the system microprocessor from starting to operate with insufficient voltage and prior to stabilization of the clock oscillator. It ensures that operation is precluded until internal registers are properly loaded, FPGA's have downloaded their configuration data prior and all system power supplies are above minimum operating levels and stable. The reset signal remains active until VDD rises above the minimum preset voltage level for time period tPD. MANUAL RESET The manual-reset input (MR ) allows the user to trigger a reset by using a push-button switch or by electronically driving the input low. The input is an MR active LOW debounced input. Reset is asserted anytime the pin is pulled low to less than 100mV MR for the minimum pulse width or longer. The reset MR output remains asserted low for tPD , typically 120ms and then is released. Figures 2 and 3 illustrate the CAT885's operation and output response times. RST
VDD/ VDD2 0 MR 0 RST 0
VTH1/2 1V >TPW
tPD
tRPD
tPD
tPD
tRPD
Figure 2. Power Supply Monitoring Diagram
VMON VTH 0 tRPD RST 0 tPD
Figure 3. Auxillary Voltage Monitoring Diagram
(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice
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Doc. No. MD-3028 Rev. C
CAT885 PACKAGE OUTLINE DRAWING
MSOP 8-Lead 3 x 3mm (Z)
(1)(2)
SYMBOL
MIN
NOM
MAX
A A1 A2 b c D
E E1
1.10 0.05 0.75 0.22 0.13 2.90 4.80 2.90 0.40 3.00 4.90 3.00 0.65 BSC 0.60 0.95 REF 0.25 BSC 0 6 0.80 0.10 0.85 0.15 0.95 0.38 0.23 3.10 5.00 3.10
E E1 e L L1 L2
TOP VIEW
D
A
A2
DETAIL A
A1
e SIDE VIEW
b
c END VIEW
L2 L L1 DETAIL A
Notes: (1) All dimensions are in millimeters. Angles in degrees. (2) Complies with JEDEC standard MO-187.
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(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice
CAT885 EXAMPLE OF ORDERING INFORMATION (1)
Prefix
CAT
Device # Suffix
885 Z I -L S -G T3
Package Z: MSOP Company ID Product Number 885
Voltage Detection VDD Level S = 2.87V L = 4.63V
Temperature Range I = Industrial (-40C to 85C)
Voltage Detection VDD2 Level T = 3.08V S = 2.95V Z = 2.33V A = 1.68V
Tape & Reel T: Tape & Reel 3: 3,000/Reel Lead Finish G:NiPdAu
ORDERING INFORMATION
Part Number CAT885ZI-ST-GT3 CAT885ZI-SS-GT3 CAT885ZI-SZ-GT3 CAT885ZI-SA-GT3 CAT885ZI-LT-GT3 CAT885ZI-LS-GT3 CAT885ZI-LZ-GT3 CAT885ZI-LA-GT3 VDD 2.87V 2.87V 2.87V 2.87V 4.63V 4.63V 4.63V 4.63V VDD2 3.08V 2.95V 2.33V 1.68V 3.08V 2.95V 2.33V 1.68V Package MSOP MSOP MSOP MSOP MSOP MSOP MSOP MSOP
Notes: (1) All packages are RoHS-compliant (Lead-free, Halogen-free). (2) The standard finish is NiPdAu. (3) The device used in the above example is a CAT885ZI-LS-GT3 (MSOP, Industrial Temperature, 4.63V (VDD) and 2.95V (VDD2) Detection Levels, NiPdAu, Tape & Reel, 3,000/Reel). (4) For additional detection voltage, package and temperature options, please contact your nearest ON Semiconductor Sales office.
(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice
7
Doc. No. MD-3028 Rev. C
CAT885 REVISION HISTORY
Date 05-May-08 06-Nov-08 03-Aug-09 Rev. A B C Description Initial Release Change logo and fine print to ON Semiconductor Update Functional Block Diagram
ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. "Typical" parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including "Typicals" must be validated for each customer application by customer's technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
PUBLICATION ORDERING INFORMATION
LITERATURE FULFILLMENT: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303-675-2175 or 800-344-3860 Toll Free USA/Canada Fax: 303-675-2176 or 800-344-3867 Toll Free USA/Canada Email: orderlit@onsemi.com N. American Technical Support: 800-282-9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910 Japan Customer Focus Center: Phone: 81-3-5773-3850 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative
Doc. No. MD-3028 Rev. C
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(c) 2009 SCILLC. All rights reserved. Characteristics subject to change without notice

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