Real-Time Clock And Calendar; Trigger In Specifications; Trigger Out Specifications - Fluke 2680A Service Manual

Real-Time Clock and Calendar

The next table provides a summary of the battery powered real-time clock and calendar.
Specification
Accuracy
Battery Life

Trigger In Specifications

The following table provides a summary of the Trigger In specifications. The Trigger In
input is located on the rear panel connector, terminals Trigger In and Signal GND.
Specification
Logical High - Trigger not set
Logical Low - Trigger set
Compatibility
Isolation
Minimum Pulse Width
Maximum Frequency
Repeatability

Trigger Out Specifications

The next table provides a summary of the Trigger Out specifications. The Trigger Out
output is located on the rear panel connector, terminals Trigger Out and Signal GND.
Specification
TTL Logical Zero - Trigger Out Set
TTL Logical One - Trigger Out Not Set
Non-TTL Logical Zero - Trigger Out Set
Non-TTL Logical One - Trigger Out Not Set
Pulse Duration (Logic Low)
Isolation
Table 1-2. 268X Real-Time Clock and Calendar
1 minute per month for 0 C to 50 C range
>5 unpowered device years for 20 C to 28 C (68 F to 82.4 F).
Table 1-3. Trigger In Specification
Table 1-4. Trigger Out Specification
Introduction and Specifications
Characteristic
Characteristic
Minimum: 2.0 V
Maximum: 7.0 V
Minimum: -0.6 V
Maximum: +0.8 V
TTL or Contact Closure
None (dc coupled)
5 µs
Nominal 400 Hz
3 ms
Characteristic
0.8 V maximum for an Iout of -1.0 mA (1 LSTTL
load)
3.8 V minimum for an Iout of 0.05 mA (1 LSTTL
load)
1.8 V maximum for an Iout of -20 mA
3.25 V minimum for an Iout of -50 mA
125 µs
None
Real-Time Clock and Calendar
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