That 12v 9Ah battery should be capable of powering everything. Lead acid batteries can usually supply high currents for short periods. But I can't say how long it will be until the battery needs recharging. I would assume 9Ah really means 3 or 4.You can certainly connect the battery to the Arduino. However do NOT draw current for the other device through the Arduino....RPS ... do not leave a lead-acid battery in a discharged state - it will greatly shorten its life.
You have already mentioned this battery in your other thread.https://forum.arduino.cc/index.php?topic=541078.0You could have asked it there.If you want to charge a 12volt SLA battery, then connect a 12volt SLA battery charger to it.I always get nervous when powering an Arduino with more than 9volt (>= 13.5volt in this case).The 5volt regulator on the Uno could overheat, depending on what else the Uno has to power.You might want to power the Arduino with a 5volt buck converter (on the 5volt pin).Leo..
so how can i control the servo motor and the HC-SR04 if i will not draw any current from other devices from arduino?
Powering the HC-SR04 from the Arduino 5v pin is probably OK, but not the servo.If (as @Wawa has suggested) you use a 5v regulator to power the Arduino then you could also use that to power the Servo and the HCSR04. If it is a small servo the 500mA should be sufficient....R
i have posted my servo.. can u plss suggest what should i do to control it.. why cant i use the 5v pin of arduino to control it?
When you say "control" presumably you mean "power", because you will control it with a 5V digital output; powering it is a different matter.According to this page, that MG996R servo needs substantial current. When it's running it draws 500-900mA, but more to the point at stall it requires 2.5A. Stall current is what it draws for a short time each time it starts to move, and of course any time it actually jams.So you need to provide at least 2.5A just for the servo.
so i cant use the 5v pin of arduino? so it means i need extra power supply just for the servo?
Just looking at the site you listed before I would go for:https://www.lazada.com.ph/products/lm2596s-dc-dc-buck-converter-step-down-adjustable-power-module-i6005010-s7605914.htmlIf you're planning to use the servo heavily I would add a small heat sink but if you don't tend to let the servo stall/move heavy stuff it's fine.
You can but I wouldn't The HC-SR04 is pretty low current and it likes a stable voltage. A servo is a beast when it comes to current which will probably make the 5V prone to having spikes and dips. Not a problem for the servo but it is for an IC. And because the HC-SR04 is low current you can connect it to the Arduino 5V which is decoupled from the servo and thus more stable.
Of course, just describe into detail what you want, what you have (code and schematic (NO Fritzing breadbord mess) and what the problem is (does not work doesn't cut it ).