AS1926 Supervisor IC

Description

The AS1925/AS1926 microprocessor supervisory cir­cuits were designed to assert a single reset if the moni­tored supply voltage drops below its reset threshold or if the manual reset is activated. The reset remains asserted for a fixed timeout delay after VCC has risen above the reset threshold and the manual reset is deas­serted.

Their small size, excellent circuit reliability, and low sup­ply current (3.5µA) make the AS1925/AS1926 a very low cost solution by eliminating external components and adjustments when used with low-voltage (+0.9V to +1.5V) systems.

The devices are available as the following standard products:

The active-low open-drain reset output requires a pullup resistor that can be connected to a voltage from 0 to VCC. The reset comparator was specifically designed to ignore fast VCC transients.

The devices are available in a 5-pin SOT23 package.

Key Features

• Factory-Trimmed Reset Thresholds for Monitoring Supplies from 0.9V to 1.5V
• Low Power Consumption: 3.5µA
• Reset Threshold Accuracy Over Temperature: ±2.5%
• Four Timeout Periods: 1.5ms, 30ms, 210ms, and 1.68s
• Three Reset Output Types:
  • Active-Low Push/Pull
  • Active-High Push/Pull
  • Active Low Open-Drain
• Guaranteed Reset Valid to VCC = 0.55V (Active-Low)
• Manual Reset Input
• Immune to Fast VCC Transients
• 5-pin SOT23 Package

Applications

The device is ideal for portable and battery-powered systems, embedded controllers, intelligent instruments, automotive systems, telecommunications equipment, networking equipment, computer workstations and servers, critical CPU monitoring applications, and any low-voltage application.

Block diagram for AS1926 Supervisor IC