Iceriver KS series hashboard repair guide

This tutorial is based on the repair experience of KS3 and KS3L. The repair methods of other models are roughly the same as this model.

①. Use a barcode scanner to record the whole machine SN code, power supply SN code, and whole machine MAC address code. If you replace the power supply, be sure to stick the whole machine SN code on the power supply to the new power supply.

②. Upload the cause of the fault and the maintenance record.

③. After replacing any accessories, the PCB board has no obvious deformation. Check whether there are open circuits or short circuits in the replaced parts and the surrounding parts. After the repair, the computing board must be tested more than twice and all are OK before it can pass!

④. Check the tools to see if the test tools can work properly.

⑤. If there are electrolytic capacitors or LED lights at the fault point, be sure to protect them with high-temperature tape to prevent damage to the capacitor.

⑥. When the computing board is powered on, pay attention to the fact that the negative power cable (black) must be connected first, then the positive power cable (red), and finally the data cable. When removing the power clip, the order must be opposite to the installation order. First remove the data cable, then the positive power cable (red), and finally the negative power cable (black).

Note: The outer power terminal is the positive pole (+), and the terminal close to the plastic socket interface is the negative pole!!!

①. Working structure of KS3 and KS3L hashboards:

The hashboard consists of 112 (KS3)/56 (KS3L) ASIC chips, divided into 28 groups (28 voltage domains), each group consists of 4 ASIC chips;

When testing KS3 and KS3L on a single board, the ASIC chip operating voltage is 0.4V; the 28th, 27th, 26th, 25th, and 24th groups are powered by the boost circuit U15 to output 15.5V (KS3)/17V (KS3L) to the LDO to output 1.8V,

the 23rd-1st groups are powered by the LDO to output 1.8V with the input voltage of 2.2V; all 0.8V are provided by the 1.8V of this voltage domain through the LDO output.

ASIC chip distribution and serial number:


Corresponding voltage domain numbers and other circuit diagrams:


Each voltage domain contains 1.8V/0.8VLDO,
each two voltage domains contain a crystal oscillator

②. KS3, KS3L hashboard boost circuit

The boost power supply is from the power supply 12V (KS3)/15.5V (KS3L) to 15.5V (KS3)/17V (KS3L).

③、KS3、KS3L hash board signal direction

Each two levels of the chip share a 25M crystal oscillator, and the normal voltage is 0.9V

TX signal flow, enter from IO port 7 pin (3.3V), pass through the level conversion chip U8, and then transmit from chip 01 to chip 112/56;
when the signal flows normally, the voltage is 1.8V, otherwise it is 0V.

RX signal flow, from chip 112/56 to chip 01, after U7 level conversion, return to the control board through the 8th pin of the wiring terminal;
when the signal flows normally, the voltage is 1.8V, otherwise it is 0V

RSTN signal flow, enter from IO port 3 pin after the level conversion chip U6, and then pass through chip 01 to chip 112/56, the normal signal voltage is 1.8V

④、Common power supply

(1) Chip U15 (MP1517) 12V→15.5V/ 15.5V→17V

⑤、ASIC chip power supply is powered by 3 groups of voltages

(1) ASIC chip main voltage 0.40V

(2) ASIC chip VDDPST/VDDPLL1V8 voltage (MP2019/SGM2036) 1.8V

(3) ASIC chip VDD0P8/VDDPLL0V8 voltage (SGM2036) 0.8V,

Under normal working conditions, the normal voltage of the chip test point is:

Since KS3 and KS3L are powered by voltage division, the pin voltage of each chip must be measured based on the "ground" of the current chip,
and digital GND (0V) must not be used blindly.

Step 1: Use a barcode scanner to record the barcode on the returned hash board and the QR code on the board, and make a record.

Step 2: Connect the data cable between the tester and the hash board,

Step 3: Connect the power supply of the computing board. You need to use a DC regulated power supply (12V 2A current limiting) to power the computing board.
The outer side of the computing board power terminal is the positive pole (+), and the terminal close to the plastic socket interface is the negative pole (-).

Warning: Connect the negative pole first, then the positive pole!

When connecting the tester, be sure to connect the data cable to the data interface on the far right of the tester!

Step 4: Connect the USB to TTL cable to the tester.

Please note that the cables should be inserted according to the colors and order marked in the picture.

Then connect the USB port to the computer.

(For how to use the tester, please refer to the tester manual)

Step 5：After the tester is powered on, it automatically runs the test program.

After the program is finished, observe the results. The results show that the chip voltage, chip temperature, board temperature,
and quantity are consistent with the number of chips on the single board.

And three "success" pop-ups will appear later, indicating that the board has passed the test and the hash board is normal.

(The normal power-on current range of the KS3/KS3L single board is 0.9A. After the single board test program is run, the current range is 1.8A (KS3L), 3.8A (KS3))

When verifying the board, the DC adjustable power supply is configured as: 12V voltage, 2A current limit.

①. Phenomenon: There is no abnormality in the 12V power supply. After the program is run, the main voltage is always less than 12V

Handling method:

Step 1: Check the voltage before and after the 12V main MOS to determine whether the MOS is turned on.

MOS array

Step 2: Check the MOS enable voltage, use a multimeter to measure the T871 test point

Step 3: Check whether the Vg of the boost circuit to U9 to U13 is 22V (KS3)/26V (KS3L)

Use a multimeter to measure the voltage at T873 and the voltage before and after R34.

Step 4: Check whether the voltage of U18 is normal, including whether Vin, Vout, Ven, and Vfb are normal.

Among them, Ven=0V, Vfb=0.6V is considered normal

2. Phenomenon: 12V power supply voltage is fine, but the number of chips is insufficient, it is 0 or garbled

Solution 1:

Step 1: Measure the voltage before and after the MOS tube to see if it is around 12V

Step 2: Measure whether the two boost circuits are within the normal range by testing TP872 (15.5V (KS3), 17V (KS3L)),

TP873 (22V (KS3), 26V (KS3L)

The left picture is TP872, the right picture is TP873

Step 3: Check if the voltage of each chip is greater than 0V

If the voltage of a group of chips is near 0V, it is considered that the chip in the current voltage domain has a short circuit.

Step 4: Check whether the 1.8V and 0.8V of each group of chips are normal

Processing method:

If the 1.8V voltage or 0.8V voltage supply of the chip is abnormal,
it is necessary to determine the voltage point of each chip and determine the output status of 1.8V-LDO and 0.8V-LDO.

The left picture shows a high-voltage LDO, which is used for 1.8V power supply of 28, 27, 26, 25, and 24 levels.

The rest are ordinary LDOs, which are used for power supply of 1st to 23rd levels and 0.8V power supply of 28, 27, 26, 25, and 24 levels.

When running the single-board test program, you can judge whether the chip is normal by judging the voltage or resistance at the chip pin.

Theoretical Reference Table：

Step 5: Check the voltage of each group of chip pins to "ground" in the current voltage domain.

Method 2:

The first four steps are the same as method 1, and there are differences afterwards

Step 5: Keep the hashboard running the single-board program, and use a multimeter to measure the level at the DIR of the ASIC chip.

The measurement results are generally two types: Vdir=1.8V/0V

Step 6: Based on the test results of the first step, use a short-circuit:

Vdir=1.8V:

Use a short-circuit to pull up the PS0 pin of the ASIC chip. Note that the pull-up voltage can only be 1.8V

Vdir=0V

Use a short-circuit to pull up the SP1 pin of the ASIC chip. Note that the pull-up voltage can only be 1.8V

Step 7: Continue to observe the results of the single board test program to see if the chip is still garbled. If it is still garbled,
you need to repeat steps 5 to 7 one level higher until no garbled code is generated. In this case, it is determined that the previous chip of the current chip is abnormal.
After replacing it, perform the test single board program verification!

Step 8: As shown in the figure above, when the voltage at DIR is 1.8V, pull up the PS0 voltage. At this time, the board program automatically terminates at the 14th chip,proving that the first 14 chips are normal.
At this time, you need to continue to check backwards and pull up the PS0/SP1 signal on the voltage of the next voltage domain until the problem chip is found.

Related products:
Iceriver KS Series Tester