UM10208_2
© NXP B.V. 2007. All rights reserved.
User manual
Rev. 02 — 1 June 2007
44 of 362
NXP Semiconductors
UM10208
Chapter 6: LPC2800 DC-DC converter
2.4 Unused DC-DC converter
When the DC-D converter will not be used in a an application, most of its pins should be
tied to ground as shown in
. External power may be supplied from any suitable
source.
Fig 10. Example application hookup for battery and USB power
DCDC_V
DDO(3v3)
DCDC_V
DDO(1v8)
DCDC_V
DDI(3v3)
DCDC_V
BAT
DCDC_V
USB
START
STOP
STOP
START
DCDC_GND
DCDC_CLEAN
DCDC_LX1
DCDC_LX2
DCDC_V
SS1
DCDC_V
SS2
LPC288x
USB_VBUS
BATTERY
3.3V
BAT54C
10K
1K
22µF 10V
L1
L2
1.8V
+
L18
L17
N18
N17
N16
P18
R18
P17
M16
L16
M18
M17
T18
+