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LMZM23600EVM: Output oscillates under load when set to 12V output

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Part Number: LMZM23600EVM

We're testing an LMZM23600EVM under ideal lab conditions. When the output is jumpered for 12VDC, the output oscillates wildly (5V excursions) with input-output differential voltages less than around 4V. With higher input-output differential voltages there is no oscillation. The load is an IP video camera consuming around 1.6W of power. The power source is a quiet lab supply. All cables are short and twisted. The's no oscillation  with a static resistive load or when jumpered for a 5V output.


TPS61390EVM-020: Power supply for APD pin

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Part Number: TPS61390EVM-020

Hi Team,

Our customer would like to confirm if the APD pin voltage out in TPS61390 should be the same with VOUT?
If the VOUT will be 80V, will the APD pin voltage will also be 80V?

Our customer tried simulating the schematic using LTSpice with this EVM and the VOUT is going up to 80V but the APD pin is not showing the same voltage.

The customer is confused if he will connect his APD device to the JP1-APD or to J3-VOUT.

Thanks!

Jonathan



TLV767: looking for LDO with input max to 24V

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Part Number: TLV767

Hi Champions,

I'm looking for a LDO with the similar performance with TLV767, my request are

VIN MAX: 24V

Accuracy < +/- 1%

VOUT: 3.3V

Iout: 100mA

package less than 3mm*3mm

I see the TVL767 is very good performance, but the input voltage max is only 16V, do you have any other chip suggestions?

TLV76716+/- 0.5%10002-mm × 2-mm WSON

BQ2057W: Weird Voltage Across Sense Resistor

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Part Number: BQ2057W

Using the above circuit, I made my own battery charger using the BQ2057W to fulfill part of a school project. The battery we are using is charging, however at a vastly different rate than calculated. In the test circuit I was using, my Rsense value was .062 mOhms. The weird part was that I was only getting a 6 mOhm drop across this resistor, resulting in a charging current of only 100 mA, compared to the calculated 2 A charging circuit I was supposed to be getting. I do not know why the resistor is dropping this amount of voltage when it should be held consistent around 120 mV. I have used a couple other different sense resistors as well, including a 125 mOhm resistor, and have been getting similar strange values. Shown below are the voltage values I measured across all the pins,

10 V - Vcc

10 V - Vcomp (I disabled this pin)

7.63 V - Bat

9.87 V - Vsns

9.11 V - CC

4.98 V - Tss (Also disabled this pin)

.006 V - Across resistor

Bill Johns had been helping me with a previous question, and recommend using a couple different ICs including the BQ24004. I have ordered this part, but am still waiting and do not know when it will arrive. I had previously ordered the BQ2057W before I became aware of these parts and have been trying to get it to work just in case the part does not arrive in time. Below is the physical circuit on a breadboard that I've been using to test, please let me know if you need any more information, any help would be greatly appreciated. 

Shown above is the physical circuit disconnected from power

Shown above is the circuit connected to power. LED is on, and battery has shown progress in charging so circuit is working. Just not getting current output that I was expecting

Just showing that 110 mA charging current above.

Any help would be greatly appreciated

Thanks,

Ryan Amyette

LM5170-Q1: VCCA Behavior Problems

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Part Number: LM5170-Q1

Hello,

My group is trying to use a LM5170 as a current controller for the TIDA-01168.  Before we try to use it on the TIDA however, we tried to use a buck converter to recreate similar results as the reference design on TINA.

The problem our group has run into is the behavior of the VCCA pin, as shown below.

From the LM5170 reference design, we expect a low pass filter behavior, similar to the following figure.

We are confused as to why the simulations do not match up; we assumed the problem is somewhere around this part in our test schematic.

Attached below is the schematic we are using to simulate the LM5170.

If anybody can let us know what the problem is, it would be greatly appreciated.

Thanks!

(Please visit the site to view this file)

which is suitable part?

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Hi, All.

could you tell me which half bridge gate driver we can promote below spec?

1.Vbus :14V

2.Drive strength :2~3A

3.2 PWM inputs (customer wants to input separately from MCU, so separated input for High side and Low side is suitable).

do we have any gate drivers?

EE: cleaner

TPS546C23: Miscellaneous questions

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Part Number: TPS546C23

Hello,

 

Q1

My customer would like to use 1Kohms pullup resister for PMB_DTATA pin.

Does PMB_DATA pin have enough drive capability with the 1kohms pullup resister to make sure Vol specified by PMBus spec?

 

Q2

How much is the input capacitance at PMB_DATA pin and PMB_CLK pin respectively?

 

Best regards,

 

K.Hirano

TPS650830: TPS650930 PCH_PWRBTN# behavior

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Part Number: TPS650830

Hi Sir,

Does PCH_BTNIN# of TPS650930 directly copy from PWRBTN# ? If yes, How many time delay (mini-second or micro-second) from PWRBTNIN# to PCH_BTNIN#?

Jimmy C


TPS92692-Q1: Input current ripple issue when doing input ripple test

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Part Number: TPS92692-Q1

Hi team,

My customer is doing input voltage ripple test, and the frequency of ripple is range from 50Hz-25kHz, Upp=4V. Now they find that when the ripple frequency increases, the input current ripple will increase badly and violate the test standard value. The test waveform is attached below.

Now I have two assumptions:

1. Now they use only one cap connected to COMP, maybe the response speed is too low;

2. Now the output cap is 4.7uF, maybe the output capacitance should be larger;

Apart from these two parts, is there something else we can try to make the input current ripple smaller? Now we have tried to change the fsw, input inductor and input cap, and there is nothing changed. And before they use 220nF connected to COMP, and we changed to 33nF connected to COMP, which value is calculated by the calculator, and there is nothing changed too.

Please give us some ideas to do more test. Thanks.

Gary

BQ76920: bq78350bq76920 Factory Gain/Offset

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Part Number: BQ76920

Hello;

The 920 datasheet says "Eachdifferential cell input is factory-trimmed for gain or offset, such that the resulting reading through I2C is
always consistent from part-to-part and requires no additional calibration or correction factor application."

However, the 920's datasheet lists only oneoffset and one gain value (ADCOFFSET 0x51)?

So the equation that shows how to convert the 14-bit ADC reading into an analog voltage - "V(cell) = GAIN x ADC(cell) + OFFSET" seems to confuse the calibration statement (since each cell would have its own offset, or otherwise why would each cell require offset calibration?)

Also, I "assume" then, that the 78350 does this V(cell) = equation, and so the cell voltages my host u/C reads are already computed (?)

Thanks

REF5040: temperature output pin

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Part Number: REF5040

Hi 

The Pin_TEMP of REF5040 output voltage 575mV at 25℃, and the voltage increases 2.64mV for every 1℃ rise in temperature. Our control board runs for 30min, and the actual temperature rise of the chip is 4° c, but the feedback voltage at this point exceeds 650mV, and the temperature rise exceeds 25 ° c after conversion.According to the following description in the manual, this phenomenon is abnormal. After ABA verification, the problem can be fixed. Can the original factory help to do FA?

”This pin indicates general chip temperature, accurate to approximately ±15°C. Although this pin is not generally suitable for accurate temperature measurements, it can be used to indicate temperature changes or for temperature compensation of analog circuitry. A temperature change of 30°C corresponds to an approximate 79- mV change in voltage at the TEMP pin.“

TPS54160: TPS54160 voltage spike issue

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Part Number: TPS54160

Hi,

I'm testing TPS54160, as you can see the image below, this is the Vsw waveform, and in the red circle is the voltage spike. i'm wondering what caused the voltage spike when mosfet switching?

I think current change so quickly at the switching moment, due to U=L*di/dt, U(voltage) will have a spike. am i correct?

if you have any suggestions, feel free to tell me.

Thanks.

Best regards

Mason Liu

LM2940C: LM2940T schematic double check

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Part Number: LM2940C

Hi team

Could you please help me double check this schematic?

Best Regards,

Wesley Huang

Email: wesley-huang@ti.com

TPS2546: how to achieve Power Wake in notebook with only one power supply for TPS2546?

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Part Number: TPS2546

Customer is using TPS2546 in their note baok product. They only have one power supply source for TPS2546, so they will not switch between DCDC and LDO. They are asking how to achieve lower power consumption to stop the controller to continually detect the load and try to switch the power supply with S5 and DCP mode. Could you please help address their question? Thank you.

TPS2546: which mode is suggested for the S0 power state?

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Part Number: TPS2546

Customer is using TPS2546 in their notebook application., but not sure about which mode is suggested to configure at the beginning for S0 power state, SDP or CDP? What is the default mode for S0? Could you please help give some guidance? Thank you.


BQ25606: BQ25606RGET

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Part Number: BQ25606

on otg mode the value of VBUs=5.1V

what is the value of SYS?

Problem with designing a BMS with bq7690x

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Hey guys.Im designing a battry management system(BMS) with 10 3.7v 2600mAh li ion with 5 cells in parallel and 10 of these parallel packs will be in series to provide 37 to 42 volts.
I want to use bq769x0 as the controller that needs a mcu to communicate with. I have also a bms board that uses this IC.
In the IC datasheet there is a schematics that has only bat+ and GND for connecting the battry terminals and pack+ and pack - gor connecting the load.
There are to low side series mosfets named charge and discharge fets.
My question is that how can i add the charger+ and charger- to charge the battries?
In the board i have there are 3 power mosfets: one of them is connected to the charger- and the charger + is connected directly to the pack+ pin.
When there are charge and discharge fets so in the charge time i have to turn on the charge fet and off the discharge fet?
Im a little confused.
I will appreciate that if you help me guys.
Any other suggestions for a bms will help me a lot.

TPS568215: The maximum SW Minimum off time (tOFF) over temperature range -40oC to 150oC

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Part Number: TPS568215

Hello,

 

At TPS568215 and TPS56C215, how much is the maximum SW Minimum off time (tOFF) over temperature range -40oC to 150oC?

 

Best regards,

 

K.Hirano

BQ24072: Design review BQ24072 and/or BQ24076

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Part Number: BQ24072

I have a few different PCB that contain several polymer battery types for same GSM module SIM800C. maximum voltage for module 4.4V above that voltage will damage, recommended working voltage 4V, not less 3.8V. 

First case 12000 mAh capacity (I suspect is not single cell), second board 1000 mAh and the last case 12800 mAh batteries. All those 2 PCBs are a remote outdoor device input power feeding from 5V@1.3 A solar panel when a sunny day. The PCB needs to work for a few years at least. (I hope). The 1000 mAh PCB source of steady 12DC input and the battery is backup.

The schematics designed for BQ24076 but the comparison table Vout = VBAT + 225 mV, I changed to part number to BQ24072 in order to not damage the GSM module. But The resistors values not changed and Pin# 15 has a different function.

I am sending my question as design review issue before manufacturing prototypes, in case, not a proper design I will lose too much time and money for the final delivery of the project, and risk of cancellation. Delivery time-sensitive project. 

CSD75208W1015: no open spice model available, only encrypted pspice

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Part Number: CSD75208W1015

please provide an open spice model for the CSD75208W1015.

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