NXP Semiconductors
LPC2194
Single-chip 16/32-bit microcontroller
Table 2. Pin description …continued
Symbol
Pin
Type Description
VSSA
59
I
analog ground; 0 V reference. This should nominally be the same voltage as VSS,
but should be isolated to minimize noise and error.
VSSA(PLL)
58
I
PLL analog ground; 0 V reference. This should nominally be the same voltage as
VSS, but should be isolated to minimize noise and error.
VDD(1V8)
17, 49
I
1.8 V core power supply; this is the power supply voltage for internal circuitry.
VDDA(1V8)
63
I
analog 1.8 V core power supply; this is the power supply voltage for internal
circuitry. This should be nominally the same voltage as VDD(1V8) but should be
isolated to minimize noise and error.
VDD(3V3)
23, 43, 51 I
3.3 V pad power supply; this is the power supply voltage for the I/O ports.
VDDA(3V3)
7
I
analog 3.3 V pad power supply; this should be nominally the same voltage as
VDD(3V3) but should be isolated to minimize noise and error.
[1] SSP interface available on LPC2194/01 only.
LPC2194_5
Product data sheet
Rev. 05 — 10 December 2007
© NXP B.V. 2007. All rights reserved.
8 of 40