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Details, datasheet, quote on part number:LMC6953
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| Part: | LMC6953 |
| Category: | Power Management => Supervisory Circuits => System Supervisors/Reset => Supervisory Function |
| Description: | LMC6953 - Pci Local Bus Power Supervisor, Package: Soic Narrow, Pin Nb=8 |
| Company: | National Semiconductor Corporation |
| Datasheet: | Download LMC6953 datasheet File size : 224 kB |
| Request For quote: | Find where to buy LMC6953
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Datasheet text preview:
LMC6953 PCI Local Bus Power Supervisor
April 1998
LMC6953 PCI Local Bus Power Supervisor
General Description
The LMC6953 is a voltage supervisory chip designed to meet PCI (Peripheral Component Interconnect) Specifications Revision 2.1. It monitors 5V and 3.3V power supplies. In cases of power-up, power-down, brown-out, power failure and manual reset interrupt, the LMC6953 provides an active low reset. RESET holds low for 100 ms after both 5V and 3.3V powers recover, or after manual reset signal returns to high state. The external capacitor on pin 8 adjusts the reset delay. This part is ideal on PCI motherboards or add-in cards to ensure the integrity of the entire system when there is a fault condition. The active low reset sets the microprocessor or local device in a known state. The LMC6953 has a built-in bandgap reference that accurately determines all the threshold voltages. The internal reset delay circuitry eliminates additional discrete components.
Features
n Compliant to PCI specifications revision 2.1. n Under and over voltage detectors for 5V and 3.3V n Power failure detection (5V falling under 3.3V by 300 mV max) n Manual reset input pin n Guaranteed RESET assertion at VDD = 1.5V n Integrated reset delay circuitry n Open drain output n Adjustable reset delay n Response time for over and under voltage detection: 490 ns Max n Power failure response time: 90 ns Max n Requires minimal external components
Applications
n Desktop PCs n PCI-Based Systems n Network servers
Typical Application Circuits
On Mother Board On Add-in Cards
DS012846-23 DS012846-24
© 1998 National Semiconductor Corporation
DS012846
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Connection Diagram
8 Pin SO
DS012846-2
Top View
Ordering Information
Package 8-Pin Small Outline Industrial Temp Range -40°C to +85°C LMC6953CM LMC6953CMX NSC Drawing M08A Supplied As Rails 2.5k Tape and Reel
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Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. ESD Tolerance (Note 2) Human Body Model Machine Model Voltage at Input Pin Supply Voltage Current at Output Pin Current at Power Supply Pin (Note 3) 2 kV 200V 7V 7V 15 mA 10 mA
Lead Temp. (Soldering, 10 sec.) Storage Temperature Range Junction Temperature
260°C -65°C to +150°C 150°C
Operating Ratings (Note 1)
Supply Voltage Junction Temperature Range LMC6953C Thermal Resistance (JA) M Package 1.5V to 6V -40°C to +85°C 165°C/W
DC Electrical Characteristics
Unless otherwise specified, all boldface limits guaranteed for TJ = -40°C to +85°C, VDD = 5V, RPULL-UP = 4.7 k and CEXT = 0.01 µF. Typical numbers are room temperature (25°C) performance. Symbol VH5 Parameter VDD Over-Voltage Threshold Conditions TJ = 0°C to 70°C (Note 4) TJ = -40°C to 85°C (Note 4) VL5 VDD Under-Voltage Threshold TJ = 0°C to 70°C (Note 4) TJ = -40°C to 85°C (Note 4) VH3.3 3.3V Over-Voltage Threshold TJ = 0°C to 70°C (Note 5) TJ = -40°C to 85°C (Note 5) VL3.3 3.3V Under-Voltage Threshold TJ = 0°C to 70°C (Note 5) TJ = -40°C to 85°C (Note 5) VMR VPF RIN VOL Manual RESET Threshold Power Failure Differential Voltage (3.3V Pin 5V Pin) Input Resistance at 5V and 3.3V Pins RESET Output Low TJ = 0°C to 70°C VDD = 1.5V to 6V TJ = -40°C to 85°C VDD = 1.55V to 6V IS Supply Current (Note 3) 35 k (Note 6) Min 5.45 5.30 4.25 4.10 3.80 3.60 2.50 2.30 Typ 5.60 5.60 4.40 4.40 3.95 3.95 2.65 2.65 2.50 150 Max 5.75 5.90 4.55 4.70 4.10 4.30 2.80 3.00 2.80 300 Units V V V V V V V V V mV
0.05
0.10
V
0.8
1.50
mA
AC Electrical Characteristics
Unless otherwise specified, all boldface limits guaranteed for TJ = -40°C to 85°C, VDD = 5V, RPULL-UP = 4.7 k and CEXT = 0.01 µF. Typical numbers are room temperature (25°C) performance. Symbol tD tPF tRESET Parameter Over or Under Voltage Response Time Power Failure Response Time Reset Delay Conditions (Note 7) (Note 8) CEXT = 0.01 µF Typ 150 40 100 LMC6953 Limit 490 90 ns max ns max ms
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics. Note 2: Human body model, 1.5 k in series with 100 pF. Machine model. 200 in series with 100 pF.
Units
3
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