QUICK START GUIDE
2 | | EPC – EFFICIENT POWER CONVERSION CORPORATION |
WWW.EPC-CO.COM
| COPYRIGHT 2018
Demonstration Board EPC9514
DESCRIPTION
The EPC9514 demonstration board is a 6.78 MHz (Lowest ISM band)
highly resonant wireless power receiver capable of delivering up to
27 W as a 19 V regulated output when operating to the AirFuel™ standard
(excluding the BLE communications). This board is intended to power
products such as small laptops when used in a wireless power system.
The EPC9514 includes a Category 5 AirFuel Alliance compliant device coil
and circuit with high frequency Schottky diode based full bridge rectifier,
DC smoothing capacitor and 19 V regulator. The regulator is based on a
SEPIC converter that features a 100 V EPC2016C eGaN® FET. The power
circuit is attached to the coil. A photo of the EPC9514 is shown in figure 1.
For more information on the EPC2016C eGaN FETs, please refer to the
datasheet available from EPC at
www.epc-co.com
. The datasheet should
be read in conjunction with this quick start guide.
DETAILED DESCRIPTION
The schematic diagram of the EPC9514 is shown in Figure 2 and comprises
a tuning circuit for the device coil with a common-mode choke for EMI
suppression, a high frequency rectifier and SEPIC based output regulator.
The EPC9514 is powered using a Category 5 AirFuel compliant device coil
and by default is tuned to 6.78 MHz for the specific coil provided with it.
The tuning circuit comprises both parallel and series tuning which is also
differential to allow balanced connection and voltage reduction for the
capacitors.
Two LEDs have been provided to indicate that the board is receiving
power with an un-regulated voltage greater than 4 V (green LED) and
the red LED will illuminate when the un-regulated voltage exceeds 44 V.
The EPC9514 has limited over-voltage protection using a TVS diode that
clamps the un-regulated voltage to 46 V. This can occur when the receive
coil is placed above a high power transmitter with insufficient distance
to the transmit coil and there is little or no load connected. During an
over-voltage event, the TVS diode will dissipate a large amount of power
and the red LED will illuminate indicating an over-voltage. The receiver
should removed from the transmitter as soon as possible to prevent the
TVS diode from over-heating.
Figure 1: EPC9514 demonstration system.
Table 1: Performance Summary (T
A
= 25°C) EPC9514
Symbol
Parameter
Conditions
Min Max Units
V
Unreg
Un-regulated output voltage
12.5
48
V
I
Unreg
Un-regulated output current
1.4*
A
V
Unreg_UVLOR
UVLO Enable
Un-regulated voltage rising
25
V
V
Unreg_UVLOF
UVLO Disable
Un-regulated voltage falling
12.5
V
V
OUT
Output Voltage Range
V
Unreg_min
=
8.3 V
18.75
19.25
V
I
OUT
Output Current Range
V
Unreg_min
=
8.3 V
0
1.4*
A
* Actual maximum current subject to operation temperature limits.
Figure 2: Schematic diagram of the EPC9514 demo board.
152 mm
115
m
m
Load
Device
coil
Un-Regulated
DC output
Tuning Network
Rectifier
Regulator
Regulated
DC output
Coil connection
C
OUT
19 V
DC
C
Rect
C
Septic
Q
1
D
rect
L
lower
L
M11
L
M1
C
Mx
C
MPx
L
E1
C
Mx
L
upper