Is there any low power consumption voltage regulator chip?

sky999

Is there any low power consumption voltage regulator chip? [Copy link]

 

Powered by 18650, 3V~4.2V, it needs to be stabilized at 3.3V. However, when not in use, the microcontroller is always in a low-power state of 1uA current. However, the voltage regulator chip 1117 seems to consume a lot of power. Are there any voltage regulator chips recommended?

When the board is working, the maximum current may be 500mA, but most of the time it is in low power shutdown state.

littleshrimp

You can go to the spot website such as Mouser to filter low IQ regulators

qwqwqw2088

TPS7333Q, TPS7348Q, TPS7350Q

qwqwqw2088

Or go to TI official website to find low I q chips directly

If you choose LDO, generally LDO chips have high power consumption, but the current is more stable.
If you choose DCDC switch chip, the power consumption is low, but there may be some current ripples.

仙猫

" Use 18650 power supply, 3V~4.2V, and stabilize it to 3.3V "

This is a high requirement! To have the function of automatic buck-boost switching, the minimum input voltage should be determined first.

If it is really required to be usable at 3V, LDO should be ruled out first, and consider looking for a DC/DC with SEPIC function.

If it is allowed to be used only when the voltage is greater than 3.3V, then LDO may also be able to be used. It is better to find a chip with the lowest possible dropout.

chunyang

As mentioned above, the landlord's needs can only be met by DCDC, and it must be a buck-boost type. This type of DCDC chip can be selected from the official websites of TI, LT, etc., and the price will be more expensive.

In fact, the original poster's application is best powered directly by batteries.

dcexpert

LDOs with a maximum output of 500mA and a small quiescent current are rare. For example, XC6206, NCP551, RT9058, etc. have a quiescent current of several uA, but the maximum output current is only 100-200mA.

The output of DC/DC can easily reach hundreds or even several A, but the static power consumption is usually tens to hundreds of uA. If you want both low static power consumption and high output current, you may need to consider two ways of power supply: use LDO for the microcontroller and DC/DC for the high-power part. Normally, you can turn off the DC/DC enable, or even use MOS to cut off the DC/DC, so that the static power is low enough.

sky999

qwqwqw2088 posted on 2020-5-21 12:09 Or go to TI's official website to find low Iq chips directly. If you choose LDO, the power consumption of LDO chips is generally large, but the current is more stable. If you choose DCDC switch core...

Thank you so much!!!

sky999

Xianmao published on 2020-5-21 12:54 "Use 18650 power supply, 3V~4.2V, to stabilize 3.3V" This requirement is not low! To have the function of automatic buck-boost switching, you should first determine...

Thank you so much!!!

sky999

chunyang posted on 2020-5-21 13:31 As mentioned above, the landlord's needs can only be achieved by DCDC, and it must be a buck-boost type. This type of DCDC chip can be selected from the official websites of TI, LT, etc. The price will be...

Thank you very much!!! However, when the battery is powered, the voltage drops very quickly after reaching 3.24V.

sky999

dcexpert published on 2020-5-21 13:42 LDOs with a maximum output of 500mA and low quiescent current are still rare. For example, XC6206, NCP551, RT9058, etc., have a quiescent current of several uA, but the maximum output...

Thank you so much!!!

The microcontroller uses LDO, and the high-power part uses DC/DC. Very helpful, thank you! !

sky999

chunyang posted on 2020-5-21 13:31 As mentioned above, the landlord's needs can only be achieved by DCDC, and it must be a buck-boost type. This type of DCDC chip can be selected from the official websites of TI, LT, etc. The price will be...

Is there any way to determine the battery level when the power consumption is low?

chunyang

sky999 posted on 2020-5-21 14:00 Thank you very much!!! However, when powered by a battery, the voltage will drop very quickly after reaching 3.24V

At this point, a voltage regulator is not much better. Pay attention to the discharge curve of lithium batteries. The remaining capacity in the final stage is very limited, and over-discharge is not good for battery life.

chunyang

sky999 posted on 2020-5-21 14:11 Is there any way to determine the battery level under low power consumption?

There must be battery voltage monitoring. When it reaches a certain level, it will first warn. If it is too low, it will directly enter the standby or even shutdown state. If there is an ADC in the system, it is easy to realize continuous monitoring of battery capacity. If there is no ADC, you can use a power monitoring IC, which is generally called a "reset chip", but it can only respond to specific thresholds. Another option is a dedicated battery capacity monitoring and charge and discharge management chip, but it is more expensive than a single charging chip, so the best solution should be considered comprehensively based on your specific application needs.

chunyang

The disadvantage of direct battery power supply is that as the remaining battery power gradually decreases, the output voltage will gradually increase with the change of load. Whether it affects the circuit function and performance and if so, whether a solution with a lower price than the voltage-stabilized power supply can be adopted is the key to determining whether direct battery power supply can be used.

sky999

chunyang posted on 2020-5-21 15:14 There must be battery voltage monitoring. When it reaches a certain level, it will first warn, and then if it is too low, it will directly enter the standby or even shutdown state. If there is an ADC in the system, it is very...

I hope that the microcontroller is in a low power state when it is not working. If you need to use ADC to measure voltage frequently, you have to wake up the microcontroller all the time, which is more power-consuming.

chunyang

sky999 posted on 2020-5-25 12:52 I hope that when the microcontroller is not working, it is in a low power state. If you want to use ADC to measure voltage frequently, you have to wake up the microcontroller all the time, which is relatively...

There is no need to wake up the MCU regularly to measure the battery voltage; it can be measured during normal operation.

sky999

chunyang posted on 2020-5-25 13:05 There is no need to wake up the MCU regularly to measure the battery voltage. Just measure it during normal operation.

If you wait for a long time without measuring, once the battery is exhausted, you will not know

chunyang

sky999 posted on 2020-5-28 00:26 If you wait for a long time without measuring the battery, you will not know when it is dead.

So can you solve or even improve this problem with a voltage stabilizer?