Suppose I use alkaline batteries with total voltage range from +4.8V to +9.6V to operate a device, how should I design the power circuitry to supply those parts which require higher voltage supply.
For example, if I need to turn on a LED backlight which requires +12V supply, should I design a boost switching regulator circuit to step up the input voltage to +12V in order to supply to the LED backlight?
What if I need to operate a motor which requires +6V (@2.5A start surge, <500ms)? Should I design the +12V boost switching regulator circuit to be capable of supplying output current up to 3A and then step-down to +6V using a standard regulator or LDO for operating the motor? Or would it be better if I design another boost switching circuit to supply +6V directly to the motor from the input source?
In fact, I do also need +3.3V and +1.8V voltage supply for the rest of the circuit but I guess this is fine as I can immediately step-down from battery input source since the voltage is lower than the min. input voltage.
your are right, for the internal vcc=3.3/1.8v, you can use a regulator or ldo to generate this supply.
but for the +12, you have to use a boost circuit or charge pump. the +6v value, you can use a clamp circuit, the power could be +12v and the battery supply, when the supply is <6v, you use the +12v, if the value >6v, you can direct supply use the supply. hope it is helpful, good luck.
your are right, for the internal vcc=3.3/1.8v, you can use a regulator or ldo to generate this supply.
but for the +12, you have to use a boost circuit or charge pump. the +6v value, you can use a clamp circuit, the power could be +12v and the battery supply, when the supply is <6v, you use the +12v, if the value >6v, you can direct supply use the supply. hope it is helpful, good luck.
I remember there is an one chip solution which includes Buck, Boost, LDO and some other Power circuitry inside. Many companies provide such kind of chip, like Skyworks.
I remember there is an one chip solution which includes Buck, Boost, LDO and some other Power circuitry inside. Many companies provide such kind of chip, like Skyworks.
Yes. In fact, I was advised to design a flyback converter which can provide multiple outputs. However, I am reluctant to do so due to the complexity and tedious calculations.