Rev1.0

Preliminary and all contents are subject to change without prior notice.

© Seaward Electronics, Inc., • www.seawardinc.com • Page

7

9/4/2012

SE100

QC2.0 Interface Module

Applications Information

SE100 is a low-cost USB high-voltage dedicated

charging port interface IC for the Quick Charge

2.0 specification. It incorporates all necessary

functions to add Quick Charge 2.0 capability to

standard Adaptors, Car-chargers, and Portable

Battery Packs.

SE100

also

supports

other

solutions

with

traditional feedback schemes like opto-coupler

and secondary reference regulator SE431 as

depicted in Figure 1.

Figure 1. SE100 with Traditional Output Regulation (CV Only).

SE100 supports the full output voltage range of

Quick Charge 2.0 Class A (5 V, 9 V, or 12 V) or

Class B (5 V, 9 V, 12 V, or 20 V). It

automatically detects either Quick Charge 2.0

capable powered devices (PD) or legacy PDs

compliant with the USB Battery Charging

Specification revision 1.2 and only enables

output voltage adjustment accordingly.

Shunt Regulator

The internal shunt regulator clamps the BYPASS

pin at 6 V when current is provided through an

external

resistor

facilitates powering of SE100 externally over the

wide power supply output voltage range of 5 V

kΩ

BYPASS Pin Undervoltage

The BYPASS pin undervoltage circuitry resets

the SE100 when the BYPASS pin voltage drops

below 3.9 V. Once the BYPASS pin voltage

drops below 3.9 V it must rise back to 4 V to

enable correct operation.

Reference Input

Resister RREF at the REFERENCE pin is

connected to an internal band gap reference and

provides an accurate reference current for

internal timing circuits. The recommended value

is RREF = 127 kΩ.

Quick Charge 2.0 Interface

At power-up SE100 turns on switch N5 (see

Figure 3) in 20 ms or less after the BYPASS pin

voltage has reached 4 V. Switch N4 and output

switches N1 to N3 remain off. This sets the

default 5 V output voltage level. With D+ and D-

short-circuited the normal handshake between

the AC-DC adapter (DCP) and powered devices

(PD) as described in the USB Battery Charging

Specification 1.2 can commence. After switch

N5 has been turned on SE100 starts monitoring

the voltage level at D+. If it continuously stays

At USB cable disconnect the voltage level at D+