↧
TPS7A8300: How to measure noise like shown in Fig 56
↧
BQ28Z610: F/W issue
Part Number:BQ28Z610
Hi Sir
For BQ28Z610
1. I saw the latest F/W version is 0.20 and so far our product use 0.17 version ,Do I have to change the F/W version from 0.17 to 0.20 ?
2. Have any F/W change note document ?
3. How could I make sure the BQ28Z610 is not 0.16 version on our hand ? (date code or use EV2400 to see the H/W version?)
Thanks
↧
↧
Power management forum
Part Number:BQ34110EVM-796
After putting this on hold for a year we tried again to set this up for monitoring a 12VDC 18aH battery . Purchased the EVM and the 2400 interface and downloaded the latest BQstudio.
1. BQstudio is almost incomprehensible - the video circia 2014 is as bad.
2. We can connect and communicate from BQstudio to the EVM which has the jumpers set correctly .
3. Try as we may the voltage display in BQstudio is 3745mV BUT on the battery it is 12.44 Volts.
4. Does anyone have a step by step guide of how to set this up correctly - if so please email me- hedley@cynaps.co.za
↧
BQ27Z561EVM-011: PWR LED turns on when battery is connected.
Part Number:BQ27Z561EVM-011
Hi,
from yesterday, my BQ27Z561EVM-011 doesn't work. It comes out a very wired behavior that when only battery is connected to the EVM, the PWR LED turns on. I have already kept this EVM working for one month. During that time, it work perfectly. But the PWR LED never turns on when only the battery is connected. I check the schematic. There is no information about PWR LED is connected to battery. Anyone could help me find the reason?
Thanks,
Wenlong
The photo of the wired behaviour:
The schematic of BQ27Z561EVM-011:
↧
BQ25895: Why soft start time is related to configuration of D+ D-?
Part Number:BQ25895
Hi
my customer test on our EVM with 5V DC source, no battery, no load on VSYS.
When D+ D- floating, the SYS will reach VSYSMIN about 0.78s later than VBUS reaches 5V. Shown below: (red-VBUS, yellow- VSYS)
When D+ D- floating, the SYS will reach VSYSMIN about 2.75s later than VBUS reaches 5V. Shown below: (red-VBUS, yellow- VSYS)
This should not be related to the process of INPUT SOURCE TYPE DETECTION because both converter started switching about 258ms later than VBUS reaches 5V shown below which means the INPUT SOURCE TYPE DETECTION finished within 258ms.
So the question is:
1. Why different D+ D- configuration lead to such a big difference of soft start time?
2. Which configuration can minimize the time?
↧
↧
TPS53659: FW Issue
Part Number:TPS53659
Hi Team
what is value in general we set in address 24h that make VR FW cannot be burned into TPS53659RSBR?
thnaks
TPS53659RSBR
↧
LMZ30606: Using INH/UVLO with PGOOD ?
Part Number:LMZ30606
Hello,
I'm using the TPS7A8701 connected to LMZ30606.
I wish to connect the PGOOD of the TPS7A8701 to the LMZ30606.
Is it possible to connect it to the INH/UVLO pin ?
Should we use any pull up resistor on this pin ?
Can you please advise how to daisy chain the PGOOD between the two devices ?
Regards,
↧
TPS62420: calculation of feedback resistors
Part Number:TPS62420
Hello,
I'm using the TPS62420 for converting 5V to 2.5V/0.19A
I'm using figure 14 as a reference.
I've calculated R21=887Kohm and R22=280Kohm.
I've also noticed the commend on p.21 sating that the two resistors should be around 1Mohm.
In my case it's about 1.16Mohm..
I've also noticed that in the example on figure 14 below the sum of the two resistors is 1.045Mohm
1. Is it safe to work with these current resistors values ?
2. Can you please explain the 1Mohm limitation on the datasheet ?
Regards,
↧
BQ35100: Calculating remaining battery percentage in accumulator mode
Part Number:BQ35100
Hi!
I am trying to calculate the remaining battery capacity with LiSocI2 battery. Is accumulator mode the correct mode to do this?
I do the following sequence:
-Check that [GMSEL1:0] in Operation Config A = 00.
-Setting GE=1.
-GAUGE_START
-Check that ControlStatus() [GA] = set
-Read AccumulatedCapacity
-(try to) calculate (designCapacity - accumulatedCapacity)/designcapacity to get the percentage
(and then repeat the last 2 steps to get the changing value)
The problem is, that the AccumulatedCapacity() is over 4,29E9 and it lessens every round. For example, the uint values I get are:
4,294,962,398 (first round)
4,294,962,289 (second round, 10s after first round)
Am I doing something incorrectly? Or how should I be able to read the correct Accumulated capacity?
↧
↧
LM1085: Charged-device model (CDM) value
Part Number:LM1085
Hi Team,
Please help to confirm the Charged-device model (CDM) value of LM1085ISX-ADJ/NOPB
Thanks
↧
TPS61120EVM-205: Can TPS61120EVM-205 schematics and PCB source files be provided?
Part Number:TPS61120EVM-205
Can TPS61120EVM-205 schematics and PCB source files be provided?
↧
LP87524J-Q1: power sequence controlling
Part Number:LP87524J-Q1
Hi Team,
My customer is interested in 4 channel automotive PMIC solution. We see LP87524J -Q1 is a potential candidate, but customer has a question on PMIC controlling.
LP87524J -Q1 is a 4 channel output PMIC, but it has 3 EN pins only. If my customer does not use I2C to control the PMIC, how can they control the 4th PMIC output?
Best regards,
Andy Chu
↧
LM25037: Low to no load ripple problem
Part Number:LM25037
I have been dealing with a light load problem on this device.
I am using the chip in feed forward voltage mode.
The FB pin is tied to ground and the Comp pin is connected to the Collector of a BJT. The BJT is then driven by my control loop. By changing the set-point in the control loop i am now able to adjust my output voltage. All that works great as long as i have a load on my output.
The problem is that i am seeing a low frequency ripple at the output of my secondary side at low to no load.
To isolate problem i did the following:
I took the control loop out of the equation and tied a potentiometer to the comp pin so i can manually adjust the output. The problem remained unchanged.
I am able to line up the output ripple with some regularities i see on the comp pin. I attached several scope grabs.
No Load 2ms:
The problematic noise can be seen on channel 4.
No Load at 40us:
Half load 2ms:
Half Load 40us:
↧
↧
BQ25703A: bq25703A ILIM_HIZ pin
Part Number:BQ25703A
what is the function of the pin ILIM_HIZ? How to connect this pin with a divider bridge? What resistance values i use ?
↧
TPS23750: 24V AUX power to TPS23750
Part Number:TPS23750
Hi,
As per slvs590b.pdf document, the TPS23750 is designed to operate from 24V adapters when we use Auxiliary Power ORing option-2.
Can you please confirm, will the circuit below (reference:TPS23750EVM-107) work if I connect 24V to the marked point? Do I need to add more components(capacitors) to make it work?
Thank you.
↧
LM25069: LM25069 damaged in short current test
Part Number:LM25069
Hi team,
As my customer use LM25069 as the overcurrent and short current protection device, but we find the device OUT pin is easy to be damaged, and we find there is a negetive spike voltage(<<0.3V) when do the short current test.
I go thru your old E2E threads, you recommended to add a 1k resistor on the OUT pin and a shotkey diode in parallel. We do so, it works in 50A current, but because the customer actual design demand is to protect a 100A overcurrent, then the dI/dt would be very big. then the OUT pin still would be damaged.
I want to know, if we replace the 1k resistor with a diode is a good idea to prevent the negetive spike goes lower than 0.3V under the worst scenario? Thanks.
Regards,
Robin Liu
↧
BQ24650: Regarding application report SLVA437A Revised OCT 2011.
Part Number:BQ24650
Hello,
I have been looking through the Application Note # SLVA437A - Revised Oct 2011.
Please clarify the following ...
1) On Page 5, Step 5 it states that a resistor R23 needs to be added between the junction D5 and R21 and Gnd to protect the FET Q3 from over voltage if Vin exceeds 20V. However the schematic on page 2 shows this resistor as being R24 - NOT R23. Is this a typographical error
2) There are 2 gnds shown in the schematic on Page 3. The earth Grd ( three horizontal slashes) appear to be for the purpose of noise immunity but are the system load and the battery sharing the same gnd ?
3) It's my intent that this circuit be design around a 24 volt lead acid battery. Apart from the difference in my Ah specs for the battery, the higher float and bulk charge voltages it would appear that I could use the same resistance parameters provided I use the same Vref and the 40mV differential constants. Would you agree ?
Regards
Dave
↧
↧
BQ76PL455A: 3.3V MCU power source for 50S solution
Part Number:BQ76PL455A
Hi Team,
For 50S solution, I am trying to leverage PL455 x4pcs for this design. However, we need to apply 3.3 V to MCU. In EM1402, the power is applied from external USB.
I am thinking if there is any LDO or others from PL455 for this purpose. Could you give me your comment?
↧
LM25085-Q1: Power management forum
Part Number:LM25085-Q1
I've implemented the suggestions for avoiding failures (i.e. a shottky diode from Vcc to GND.
nevertheless I've got failures again switching on and off and on again. The AC/DC converter has a quiet output w/o under or overshoot.
the only difference with a recommended bom is Cadj=22nF instead 1nF (recommended value).
Someone has some more hint?
thanks
↧
TPS2561: FAULT line not asserted during overcurrent event
Part Number:TPS2561
I am using the TPS2561 to current limit a pair of USB ports, with each port limited to 560mA. When I create a short to GND on the output using an NFET circuit, the current is limited to around 560mA and the voltage falls to around 150mV. However, the FAULT line is not asserted low during this event. FAULT is being pulled up by a 100kOhm resistor. The Ilim resistor value is 100kOhm.
I have also tried a current limit of 1A using a 48.7kOhm resistor and had similar results, with the current being limited at 1.082A and the voltage falling to 1.186V. In this case as well the FAULT signal remains high.
↧