Agilent Technologies E4350B, E4351B Output Held High Troubleshooting, Output Held High Start

Page 19

Output Held High Troubleshooting

"Output Held High"

Start

Turn supply off and remove the top cover. Disable the Overvoltage circuit by shorting A1U410 pins1 & 2 and lifting A1R447. Turn the supply on and check the secondary bias and reference voltages (TP’s 9 through 12 See Table 6-3).

Caution: During these tests, the output may be at hazardous levels.

 

 

 

 

 

 

 

 

 

 

Troubleshoot the defective

 

Voltages OK

 

No

 

 

 

 

 

 

 

 

curcuit. See Fig. 6-5 Sheet 1.

 

?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Program voltage and current to 1/2 full scale. Check

 

 

 

voltage at A5J722-15 (TP25) and A5J722-16 (TP24)

 

 

 

to common (TP9). Voltages should be

 

 

 

 

 

 

 

* Load output to 5% rated current

approximately -2V.

 

 

 

 

 

 

 

and check drop across emittor

 

 

 

 

 

 

 

 

 

 

 

 

resistors on left boards A4A1 &

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A4A2 (R201, R206, R216) and

 

 

 

 

 

 

 

 

 

 

 

 

on right boards A4A2 & A4A4

Voltages OK

 

No

 

 

 

Replace A5 DSP board

 

(R301, R306, R311, R316) to

 

 

 

 

 

help isolate defective stage (see

?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig 6-6 and 6-7). A defective

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

stage will be conducting more

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

current.

Check if CV "OR" gate diode A1D411 is conducting.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A1D411 Conducting

 

No

 

 

Check A1U408, D411

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Disconnect cables from Top

?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Tunnel boards A4A1 and

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A4A2.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Output OK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

?

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

Check output control voltage at

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No

 

A1R638 (TP36) to common (TP9).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reconnect top tunnel

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

boarda and disconnect

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

cables from Top Tunnel

A1R638 approx. 12mV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

boards A4A3 and A4A4.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No

Check A1U408, U409

Reconnect Tunnel boards

 

 

 

Output OK

 

Yes

 

one at a time to isolate

 

 

 

 

 

?

 

defective board.*

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check A1U408. Voltage at

 

 

 

 

A1R511 should be >8V.

 

 

 

 

 

 

 

 

Figure 3-9. Output Held High Troubleshooting

Service Addendum

19

Image 19
Contents Areas of Difference ForewordTable of Contents Test Equipment Required Firmware RevisionsMeasurement Techniques Basic Test SetupCC RMS Noise Measurement Test Setup Transient Recovery TimeVoltage and Current Values Load Effect Source Effect Pard Ripple & Noise Performance Test RecordCurrent Sink 0.9A Readback Accuracy Pard Ripple & Noise Signature Analysis Self-Test Error Codes/MessagesOverall Troubleshooting sheet 1 Overall Troubleshooting sheetOverall Troubleshooting sheet 2 Overall Troubleshooting sheet 3 Overall Troubleshooting sheet 4 OV & OC Flow ChartsNo Display Troubleshooting No Display TroubleshootingOV Will Not Fire Start OV Will Not Fire TroubleshootingOV at Turn-On Start OV at Turn-On TroubleshootingOutput Held Low Start Output Held Low Troubleshooting sheetOutput Held Low Troubleshooting Sheet 2 Output Held High Start Output Held High TroubleshootingClear Screen Case Else Next 18. Cable and Connector Locations for E4350B/E4351B Cable and Connector LocationsDSP Board Digital Signal Processor DSP Board DSP Simplified Diagram of DSP CircuitsChassis -Mechanical Page Page Page Page Mosfet Page Page Page Page STUD-STD-PRS-IN Service Addendum FET Q303 1855-0849 FET Mechanical Test Points Signal Measurement and Conditions A4A1/A4A3 Left Tunnel Boards Figure Adapter Board and Phone Adapter Board Figures 6-11 A1 Main Board Assembly Diagram and Test Points for E4350B A1 Main Board Schematic Diagram for E4350B sheet 1 A1 Main Board Schematic Diagram for E4350B sheet 2 A1 Main Board Schematic Diagram for E4350B sheet 3 A1 Main Board Schematic Diagram for E4350B sheet 4 A4 Left Tunnel Circuit Component Locations for E4350B A4A1/A4A3 Left Tunnel Circuit Schematic Diagram for E4350B A4A2/A4A4 Right Tunnel Circuit Schematic Diagram for E4350B 10. A5 DSP Board Test Points 11. A6 Adapter Board Schematic Diagram

E4351B, E4350B specifications

Agilent Technologies, a leader in electronic measurement, offers a range of advanced solutions, including the E4350B and E4351B switching systems. These models are specifically designed to meet the increasing demands of modern testing environments, providing high reliability and precision for a variety of applications.

The Agilent E4350B is known for its low resistance switching capabilities, making it an ideal choice for applications requiring accurate and repeatable measurements. It supports up to 16 channels of low resistance testing, allowing engineers to simulate complex electrical paths and identify potential issues in circuit designs. With an optional temperature measurement capability, users can monitor the thermal performance of components directly during tests.

On the other hand, the E4351B model enhances flexibility with a modular design, offering an extensive range of input and output configurations. This instrument is particularly well-suited for automated test systems, providing the ability to connect multiple devices and manage them seamlessly. Its high-speed switching technology enables quick toggling between channels, ensuring that large datasets can be acquired swiftly without compromising accuracy.

Both models employ advanced contact technology, which minimizes the potential for signal degradation, ensuring that users receive reliable data with minimal noise interference. This feature is crucial in applications where signal integrity is paramount, such as in research and development or quality assurance processes.

Enhanced user interfaces simplify operations for both novice and experienced technicians. The built-in touchscreen and intuitive navigation allow for easy setup and operation, significantly reducing the learning curve. Furthermore, the comprehensive software support provided by Agilent facilitates integration with various programming environments, allowing for custom test sequences tailored to specific needs.

Moreover, both E4350B and E4351B systems are built with durability in mind. The robust construction ensures long-term reliability, reducing downtime and maintenance costs. This makes them ideal candidates for both laboratory settings and field operations where consistent performance is critical.

In summary, Agilent Technologies’ E4350B and E4351B models are distinguished by their precision, flexibility, and robust performance. Their advanced features and user-friendly design make them suitable for a wide variety of applications, from routine testing to complex R&D projects. By leveraging modern switching technologies, these systems set a high standard for electronic measurement, aiding engineers in developing reliable electronic solutions.