Used together, the GreenChip TEA1720A and TEA1705 are high-performance, low-power controllers for mobile device chargers up to 10-W.
The ICs are the latest additions to the energy-saving GreenChip power IC portfolio, which as of March 2013 has shipped its one-billionth device worldwide.
The latest GreenChip solution introduces an innovative architecture that uses the secondary side (TEA1705) for load-step detection, generating wake-up interrupts to the primary side (TEA1720A) in burst mode. The TEA1720A is the primary sensing SMPS (switched mode power supply) controller driving an external bipolar transistor, while the TEA1705 functions as the secondary-side transient controller. Together, the TEA1720A and TEA1705 deliver a fast transient response (5V ±5%). This approach supports the use of smaller output capacitors – 2 x 270 μF or lower – which, combined with the high integration level of the overall GreenChip solution, reduces the PCB space required and enables chargers in a compact form factor of about 1 inch3. It also enables low no-load power consumption of less than 10 mW.
The GreenChip TEA1720A and TEA1705 controllers are compliant to the USB battery charging specification, as well as ENERGY STAR 2.0 and new US Department of Energy efficiency standards going into effect in 2014. The TEA1720A includes integrated high-voltage (HV) start-up for fast start-up time (<200 ms) without external bleeder circuitry; primary sensing, which eliminates the need for an optocoupler; an integrated emitter switching device; and integrated protection features such as over-voltage protection (OVP) with auto-restart function, under-voltage lockout (UVLO) and clamp protection. Further, the solution offers significant savings using the external NPN transistor.
The GreenChip TEA1720A and TEA1705 are sampling with lead customers now and scheduled to go into mass production in Q2 2013. The TEA1836 will be introduced in the second half of the year.
More information about the GreenChip TEA1720A controllers at
More information about the GreenChip TEA1705 controllers at