Quantcast
Channel: Power management forum - Recent Threads
Viewing all 35901 articles
Browse latest View live
↧

LP8860-Q1: About pin setting

March 25, 2019, 3:49 am
↧
Search

TPS2372: 12.5k Phihong detection

March 25, 2019, 4:18 am
$
0
0

Part Number:TPS2372

Hi All,

I'm developing a PD with the TPS2372 and I have a doubt about Phihong 12.5K detection resistor. When a Phihong injector detects a 12.5k resistor, it delivers power through the 4 pairs, but it still does classification?.

When my PD is configured to be used by an IEEE802.3bt PSE it is set  as Class 6 ( 24.9k detection) but when it is set to 12.5k detection resistor should it be set as class 4 or class 6?, or it is irrelevant as CLSA is 63.4ohm for Class 4 and Class 6 anyway?.  I have a switch to change from 24.9K detection to 12.5k and I don't know if I should use to change from 24.9k and Class 6 to 12.5k and Class 4.

Thanks,

Winsu

↧
↧

BQ24250: BQ24250 - EN1, EN2 and Vdpm..

March 25, 2019, 4:19 am
$
0
0

Part Number:BQ24250

For my project I try different charging chips, I have questions about the BQ24250 IC:

1) Do Vdpm values need to be set by resistors R1 and R2, or is this value set by bits B0-B2 in register #5?


2) Pins EN1 and EN2 - the levels on them do not affect the charging current, why? Because I configured the IC via the I2C bus?

3) Did I understand correctly that the BQ24250 cannot determine the type of charger and use the B4 bit (DPDM_EN) is not necessary?

↧

UCC39002: How many PSU can I implement parallel in a system?

March 25, 2019, 4:21 am
$
0
0

Part Number:UCC39002

Hi Team,

Do you have any experiments or experience of parallel PSU using UCC39002?

What's the maximum PSU unit can we parallel in a system? if we would like to parallel more than 10 PSU units. Do you have any suggestion on this?

Meanwhile, I noticed there was another current sharing controller called UCC3902 which biggest difference between UCC39002 is differential current sharing signal. 

It seems to me, the differential current sharing bus(UCC3902) has better noise immunity than the single-end current(UCC39002) sharing bus. 

Is UCC3902 more suitable for our requirements? 

Thank you.

Muhsiu.

Noise immunity
↧

TPS74801: Add a 2.2 Ohm to 5V on bias pin

March 25, 2019, 4:24 am
$
0
0

Part Number:TPS74801

Hi, team

My customer have a application like the picture below, which add a 2.2 ohm resistor pull up to 5V.

Does this have a concern ? 

From the datasheet, " BIAS pin current's " current limit is 2mA. 

Does this resistor should be at least 5.1k ohm to fit the Bias pin current?

↧
↧

TPS74401: TPS74401

March 25, 2019, 4:47 am
$
0
0

Part Number:TPS74401

requirements: Vin=3.3V, Vo=2.5V/1A.

Is it possible to connect VBIAS to Vin?

As I understand from the datasheet for normal operation VBIAS ≥ Vo+1.62V. It means that I can’t, but I want to verify with you?

↧

TPS51285B: TPS51285B phase & gain margin

March 25, 2019, 5:22 am
$
0
0

Part Number:TPS51285B

Dear all，

could you please give Comments about TPS51285B below duo to our customer's requirement.

1. Is it possible to test the  according to the circuit design of the accessory?
2. If you can test, please help provide the test method?
3. If not, may you use your own Demo board to verify the loop stability according to the accessory parameters (or commissioning parameters)? Can I share test reports or verification results? thank!

Eason

↧

BQ40Z80: Time of Wake up from Shutdown

March 25, 2019, 5:34 am
$
0
0

Part Number:BQ40Z80

Hi TI experts,
For user to have good experience, we want to know below question. Would you help me to check?
1. What's long time requirement to get voltage at pack+(ignore mosfet turn on rise time) from shutdown to wake up? Need the longest time value.
2. What's long time requirement to get SMBus data from shutdown to wake up? Need the longest time value.
Many thanks.
↧
Search

BQ24650: Setting charge voltage with a microcontroller

March 25, 2019, 5:55 am
$
0
0

Part Number:BQ24650

Is it possible to set the charge voltage of the BQ24650 with a microcontroller instead of a voltage divider?

I was thinking of something like a DAC output feeding into the Vfb pin, but I do not know how that would work exactly.

Does somebody have an idea?

↧
↧

P2P solution with APL3526 (6A Load Switch with Soft Start)

March 25, 2019, 6:03 am
$
0
0

Hi sir, 

My customer is surveying APL3526 (6A Load Switch with Soft Start) for AIO projects. 

P2P is required, please kindly suggest. 

If we don't have P2P, please kindly suggest the best suitable solution, thanks!

↧

P2P solution with GS7166 (3A Ultra Low Dropout Linear Regulator)

March 25, 2019, 6:06 am
$
0
0

Hi sir, 

My customer is surveying GS7166 (3A Ultra Low Dropout Linear Regulator) for AIO projects. 

P2P is required, please kindly suggest. 

If we don't have, please kindly suggest the most suitable solution, thanks!

↧

P2P solution with GS7612S6RM-R (High-Side Power Distribution Switches )

March 25, 2019, 6:09 am
$
0
0

Hi sir, 

My customer is surveying GS7612S6RM-R (High-Side Power Distribution Switches) for AIO projects. 

P2P is required, please kindly suggest. 

If we don't have, please kindly suggest the most suitable solution, thanks!

↧

UCD9081EVM: "No EVM found"

March 25, 2019, 6:19 am
$
0
0

Part Number:UCD9081EVM

I'm trying to use the UCD9081 EVM software, but i get this message: "no evm found. please check for cable continuity, and that the evm is powered"

I used Fusion to change the bus speed to 100kHz and to disable the PEC.

↧
↧

CCS/UCD3138A64: Implementation of timer interrupt

March 25, 2019, 6:30 am
$
0
0

Part Number:UCD3138A64

Tool/software: Code Composer Studio

I tried implementing timer interrupt on ucd3138a64 , I made T24CMPCTRL0 register's bit 1 to 1 and used hardware interrupt of irq type but i am not getting any value on IRQIVEC . From the INTREQ register i can see that an interrupt is remaining to be serviced . How should i proceed in order to obtain a timer compare capture interrupt or a timer overflow interrupt 

↧

UCD3138: Delay when switching from mode 1(Phase-shift modulation) to mode 2( frequency modulation)

March 25, 2019, 6:33 am
$
0
0

Part Number:UCD3138

Hi everyone,

I realized there is a delay in my controller when switching from mode 1(Phase-shift modulation) to mode 2( frequency modulation) in my LLC based DC/DC converter. If there is a transient being in phase-shift, the controller works properly in all range except from a zone between phase-shift and frecuency modulation). 

Is it possible there is an internal delay in the UCD when transitioning from one switching mode to anoher? 

If not, I'll assume that my phase-shift modulation is saturating before than expected.

Thanks,

Marc.F

↧
Search

BQ34110: May you give me some white paper about the relationship between battery capacity of AA battery and the voltage across?

March 25, 2019, 6:44 am
$
0
0

Part Number:BQ34110

This is not about the use of BQ34110.

We are using AA battery as our power source.

And we want to get some idea about the  relationship between battery capacity of AA battery and the  voltage across?

 As our design is designed to be low power consumption, we are urgent to get such kind of knowlege.

Would you be kind to give me such white papers? It is kind of the dischage curve of Li battery.

Thank you!

↧

BQ34Z100-G1: Best match CHEM ID has deviation of 14%

March 25, 2019, 6:50 am
$
0
0

Part Number:BQ34Z100-G1

I have run the chem id test according to the directions several times with an EVE 105 AH cell. The results of one of the test follow:

Best chemical ID : 435 Best chemical ID max. deviation, % : 13.69

Summary of all IDs with max. DOD deviation below 15%

Chem ID max DOD error, % Max R deviation, ratio
435                                     13.69                      0.9
446                                     14.42                      0.08

Max. deviations for best ID is within recommended range. Chosen best chemical ID is suitable for programming the gauge.

I am used to seeing deviation in the 7-8% range when I was testing a CALB 40 AH cell. Those tests also returned around 15 chem ids, not just two.

How should I interpret these results?

↧
↧

BQxxx Evaluation Module with separated CHG and DSG

March 25, 2019, 6:54 am
$
0
0

Messrs TI,

do you have Evaluation Module of your fuel gauge ICs with two separated channels for Charge and Discharge?

↧

TPS7A47: Noise Reduction Capacitor of TPS7A4701 and TPS7A3301

March 25, 2019, 7:54 am
$
0
0

Part Number:TPS7A47

Hi there,

we use TPS7A4701 and TPS7A3301 to supply +/- 5V  for very low noise analog application. below is sch. Some load IC is OP amplifier (OPA1632), we usually need the +/- 5V power to apply to amplifer nearly simultaneously. Which means the soft-start ramping time of 4701 and 3301 should be about the same. This limit the choice of Noise reduction cap.

For 3301, we would like to refer to datasheet section 8.1.4 "TI highly recommends using a 10-nF feed-forward capacitor and a 1-μF noise-reduction capacitor to minimize noise and maximize AC performance. ". but C_NR = 1uF will lead to 1.2s start time. this is to slow to be accepted. So we use 0.1nf as section 8.1.7 writes "To maximize noise and PSRR performance, TI recommends including 47-μF or higher input and output
capacitors, 100-nF noise-reduction capacitors, and 10-nF feed-forward capacitors, as shown in Figure 32 ". Thus, t_ss = 123ms, taking into the CFF effect on soft-start.

As a result,  For 4701, we need a 4.7uFNR cap to achieve about 116ms t_ss to be close to 123ms of 3301. This 4.7uf is much larger than 1uF mentioned  in the datsheet section 8.2.2.1.2 "Larger capacitances, up to 1
µF, affect noise reduction at lower frequencies while also tending to further reduce noise at higher frequencies ".  Not sure NR_cap = 4.7uF will be ok for TPS4701.

Hope some TI expert could give some suggetions on my concerns. Thanks.

↧

TPS61500: TPS61500 calculation spreadsheet or design tool

March 25, 2019, 7:58 am
↧
Viewing all 35901 articles
Browse latest View live
Search
<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>