ICL7149
3-3/4 Digit, Autoranging Multimeter

Key Features

• 18 Ranges
• 4 DC Voltage 400mV, 4V, 40V, 400V
• 2 AC Voltage with Optional AC Circuit
• 4 DC Current 4mA, 40mA, 400mA, 4A
• 4 AC Current with Optional AC Circuit
• 4 Resistance 4kΩ, 40kΩ, 400kΩ, 4MΩ
• Autoranging - First Reading is Always on Correct Range
• On-Chip Duplex LCD Display Drive Including Three Decimal Points and 11 Annunciators
• No Additional Active Components Required
• Low Power Dissipation - Less than 20mW - 1000 Hour Typical Battery Life
• Display Hold Input
• Continuity Output Drives Piezoelectric Beeper
• Low Battery Annunciator with On-Chip Detection
• Guaranteed Zero Reading for 0V Input on All Ranges

Description

The Intersil ICL7149 is a high performance, low power, autoranging digital multimeter lC. Unlike other autoranging multimeter ICs, the ICL7149 always displays the result of a conversion on the correct range. There is no "range hunting" noticeable in the display. The unit will autorange between the four different ranges. A manual switch is used to select the 2 high group ranges. DC current ranges are 4mA and 40mA in the low current group, and 400mA and 4A in the high current group. Resistance measurements are made on 4 ranges, which are divided into two groups. The low resistance ranges are 4/40kΩ. The high resistance ranges are 0.4/4MΩ. Resolution on the lowest range is 1Ω.