I started designing a small system.The problem is that i am designing ot for the first time and my friends suggested to power management IC's for my system to give the power.I searched through the net but I cant find any.My requirements are
Vin: 7.5 V and above
Vout: 1.2,2.5,3.3,5 V with 1A output current.Can anyone suggest any help??
Answer 1: Go for the same IC that is specified in the reference design (especially if you're new to power up sequencing). Keep in mind that not only the voltages are relevant, but the sequence in which they come up as well. The required sequence is usually outlined in the datasheet and/or hardware guidelines. Plus: this will usually also give you options such as dynamic voltage/frequency scaling.
Answer 2: Go for any device, that matches the Hardware Guidelines. These usually specify which sequence you will need. Depending on your power requirements choose an appropriate IC (manufacturers are Dialog, Freescale, TI - in no specific order). Usually they come with different interfaces such as Buck/Boost regulators and/or LDOs. Some include a reset generator, a watchdog. Usually you can interface them via I2C/SPI (sometimes there is no configuration interface available). Make sure that by setting the correct resistors you will get your output values. Sometimes it is a good idea to get the input, reduce it to e.g. 5V and generate all required voltages from these 5V (can be 7.5 as well - depends on the regulator).
Answer 3: Build it manually using transistors as "Enable" gates to ensure the correct power up sequence.
I'll add some links here for the product categories, the devices are usually called PMICs: