CAT803 , CAT809 and CAT810 are supervisory circuits that monitor power supplies in digital systems. The CAT803, CAT809 and CAT810 are drop-in replacements for the MAX803 , MAX809 and MAX803 and the MAX810 is suitable for applications in the industrial temperature range. These devices generate a reset signal that is asserted when asserted when the supply voltage falls below a preset threshold level at least 140 ms after the supply level rises above that level. The underlying floating gate technology, using the analog EEPROM ON Semiconductor can provide any custom reset threshold. Seven industry standard threshold levels are available to support +5.0 V, +3.3 V, +3.0 V and +2.5 V systems.

The CAT803 has an open-drain RESET output (active low). The CAT803 requires a pull-up resistor on the reset output. The CAT809 has a push-pull RESET output (active low) and the CAT810 has a push-pull RESET 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. CAT803, CAT809 and CAT810 are available in compact 3-pin SOT-23 and SC-70 packages.

feature

Precise monitoring

+5.0 V (-5%, -10%, -20%),

+3.3 V (-5%, -10%),

+3.0 V (-10%) and

+2.5 V (-5%) power supply

Three output configurations are available:

- CAT803: Open drain active low reset

- CAT809: push-pull active low reset

- CAT810: push-pull active high reset

Drop-in replacements for the MAX803, MAX809 and MAX810 for applications operating in the industrial temperature range

Reset is valid to VCC = 1.0 V.

6 A supply current

Power Transient Immunity

Industrial temperature range: -40°C to +85°C

Available in SOT-23 and SC-70 packages

These devices are lead-free and RoHS compliant

application

Computers, Servers, Laptops, Cable Modems

Wireless communication

Embedded Control System

white goods, power meter

smart instrument

PDAs and Handheld Devices

PIN configuration diagram

marker map

CAT803 CAT809 CAT810 Name Description

1 1 1 GND Ground

2 2 - RESET active low reset. If VCC is below the reset threshold, set RESET VCC rises above the reset threshold and remains low for at least 140 ms. - - 2 RESET Active high. If VCC is below the reset threshold, set RESET VCC rises above the reset threshold and remains high for at least 140 ms.

3 3 3 VCC Monitored Supply Voltage.

Absolute Maximum Ratings

Parameter rating unit

Any pin from -0.3 to +6.0V with respect to ground

Input current, VCC 20 mA

Output current, RESET, RESET 20 mA

Rise rate, VCC 100 V/s

Continuous power consumption

2.2 mW/°C reduction above 70°C (SC70)

4 mW/°C reduction above 70°C (SOT23)

Operating temperature range -40 to +85°C

Storage temperature range -65 to +105°C

Lead Soldering Temperature (10 seconds) 300 °C

Stresses beyond the maximum ratings may damage the device. Maximum ratings are pressure ratings only. The above functional operation does not imply recommended operating conditions. Prolonged exposure to stresses above recommended operating conditions may affect device reliability.

CAT803, CAT809 and CAT810 Block Diagram

Detailed description

reset time

The reset signal for the CAT803/CAT809 is low, high when the supply voltage is lower than the CAT810, and high when the supply voltage rises above the threshold threshold trip voltage and remains active for at least 140 ms.

Reset Timing Diagram

VCC transient response

CAT803/CAT809/CAT810 protection Ps fail to power down. A short duration of 4 seconds or less and an amplitude of 100 mV usually do not result in a false RESET. The graph below shows the negative maximum pulse duration - going to VCC transients will not cause a reset condition. As the magnitude of the transient goes further below the threshold (increasing VTH - VCC), the maximum pulse duration decreases. In this test, VCC starts at 0.5 V above the threshold and below the threshold overdrive voltage (VTH - VCC) ).

There is no maximum transient duration that causes the reset pulse and reset comparator to fatigue.

RESET active when VCC is below 1.0 V To ensure that when VCC is below 1.0 V, there is a >10 k pull-down resistor between the CAT809 RESET pin in a known state and it is recommended to use the RESET pin and GND. For the CAT810, a pull-up resistor from the RESET pin to VCC is required.

Reset is active when VCC is below 1.0 V

RESET for VCC below 1.1 V

Bidirectional reset pin interface

The CAT809/810 can be connected to the P/C bidirectional reset pin by connecting a 4.7 k resistor in series with the CAT809/810 reset output and the P/C bidirectional reset pin.

Bidirectional reset pin interface

CAT803 Open-Drain Reset Applications The CAT803 has an open-drain RESET output and therefore requires a pull-up resistor on the output for proper operation, as shown below. The open-drain output includes the ability to "wire and sum" several outputs together to form an inexpensive logic circuit. You can also connect pull-up resistors for different power supplies that may be higher than the CAT803 VCC pin. The value of the pull-up resistor does not matter in most applications, the typical value is between 5 k and 10 k.

Typical CAT803 Open Drain Circuit Configuration