KCC's Quizzes AQQ304 - A pure logic
1. Quote of the month: "I am not lazy, I'm just in energy-saving mode" - unknown
2. Quiz AQQ304 about finding a pure logic puzzle
Mike is looking at Anne, but Anne is looking at Paul.
Mike is married, but Paul is not.
Question:
Is a married
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September Monthly Blog Quiz! Read the blog, take the quiz, and you could win a gift card
Quiz: How Well Do You Know Adaptive Power Switching?
Is your I/O module overheating? The AD74416H's Adaptive Power Switching (APS) can cut heat dissipation by up to 40% — but how well do you really understand how it works?
Read the blog first: Cooling
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ADA4412-3
Production
The ADA4412-3 is a comprehensive filtering solution designed to give designers the flexibility to easily filter and drive various video signals, including...
Datasheet
ADA4412-3 on Analog.com
ADV3225
Production
The ADV3224/ADV3225 are high speed 16 × 8 analog crosspoint switch matrices. They offer a −3 dB signal bandwidth of greater than 750 MHz and a high...
Datasheet
ADV3225 on Analog.com
AD8145
Production
The AD8145 is a triple, low cost, differential-to-single-ended receiver specifically designed for receiving red-green-blue (RGB) video signals over twisted...
Datasheet
AD8145 on Analog.com
AD8146
Production
The AD8146/AD8147/AD8148 are high speed triple, differential or single-ended input to differential output drivers. The AD8146 and AD8147 have a fixed gain...
Datasheet
AD8146 on Analog.com
AD8062
Production
The AD8061/AD8062/AD8063 are rail-to-rail output voltage feedback amplifiers offering ease of use and low cost. They have a bandwidth and slew rate typically...
Datasheet
AD8062 on Analog.com
Hi,
I want to know what is the accecptable supply voltage range for the following devices as I have to choose negative 5 volts regulator which is hard to find for the required current rating (I need 2A current for these devices) :
1. ADA4412-3
2. ADV3225
3. AD8145
4. AD8146
5. AD8062
All these devices list voltage rail limits and output current limits in their respective data sheets
Each device has a quiescent current plus you must add in the load current. Just looking at the ADA4412, the max. quiescent current is 56mA and for an absolute worst case load of 150 Ohms at 2V peak on each output pin, load current = 3 x 2/150 = 40mA.
Without knowing your design I do not know how you came up with 2A current.
I am using these parts with following quantity:
| S.No. | Part number | Qty |
| 1 | ADA4412-3 | 4 |
| 2 | ADV3225 | 3 |
| 3 | AD8145 | 13 |
| 4 | AD8146 | 7 |
| 5 | AD8062 | 1 |
So that is how I have come up with a value closer to 2 Ampere. Let me know what is the tolerance of negative input voltage for these ICs?
With that many devices it is very likely the -5V rail will require 2A.
For this application the rail voltage can be +-5V +- 10% and you should not see any issues. Normally we design closer to +-2% tolerance.
My suggestion is build a spread sheet with each device, their quantity, quiescent current and load current number. Sum this all up and determine the required system rail currents.
For these loads I'd recommend going with a switching regulator. We have many to choose from.
These video parts have good PSRR numbers but it always best to keep the power rails as clean as possible.
Thanks. Based on your suggestions I have made a table with the values I could find in the datasheet. Kindly validate it & correct me if I am wrong.
| S.No | component | CURRENT (in mA) | page number in datasheet | |
| 1 | ADA4412-3ARQZ | Linear Output Current per Channel (3 channels used) | 90 | 3 |
| Quiescent Current | 56 | 3 | ||
| Total current for 1 IC | 146 | |||
| Total current for 4 Ics | 584 | |||
| 2 | AD8145YCPZ-R7 | Output Current | 50 | 3 |
| Quiescent Current | 52 | 4 | ||
| Total current for 1 IC | 102 | |||
| Total current for 13 Ics | 1326 | |||
| 3 | AD8146ACPZ-R7 | load / output current | ||
| Quiescent Current | 62 | 4 | ||
| Total current for 1 IC | ||||
| Total current for 7 Ics | ||||
| 4 | ADV3225ACPZ | load / output current | 4 | |
| AVEE, outputs enabled, no load | 70 | |||
| Total current for 1 IC | ||||
| Total current for 3 Ics |
I am unable to find the required values in the respective fields of AD8146 & ADV3225 so kindly help me out.
For your clear understanding kindly see the connectivity of these ICs below & help me with the current calculation:
The above block represents the way in which each IC is connected.
I want you to help me find the current requirement of the above 4 blocks alone individually & I will manage the rest of the current calculation by multiplying it with the number of ICs that I am using.
For ADV3225, enabled, 150 Ohm load, 1vpp signal total current is 70 + 6.66mA
For ad8146, enable, 8-150 Ohm loads, 1vpp signal, total current is 62 + 8 * 1 / 150 oHms = 115 mA. Worst case with all outputs loaded at 150 Ohms.
The output current given in the datasheet is not mentioned specifically for positive supply or negative supply so should I divide the output current by 2 assuming that the given current value in the datasheet is sum of both the supplies output current?
