Datasheet

LPC2478 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2013. All rights reserved.
Product data sheet Rev. 3.1 — 16 October 2013 26 of 93
NXP Semiconductors
LPC2478
Single-chip 16-bit/32-bit microcontroller
[1] 5 V tolerant pad providing digital I/O functions with TTL levels and hysteresis.
[2] 5 V tolerant pad providing digital I/O functions (with TTL levels and hysteresis) and analog input. When configured as a ADC input,
digital section of the pad is disabled.
[3] 5 V tolerant pad providing digital I/O with TTL levels and hysteresis and analog output function. When configured as the DAC output,
digital section of the pad is disabled.
[4] Open-drain 5 V tolerant digital I/O pad, compatible with I
2
C-bus 400 kHz specification. It requires an external pull-up to provide output
functionality. When power is switched off, this pin connected to the I
2
C-bus is floating and does not disturb the I
2
C lines. Open-drain
configuration applies to all functions on this pin.
RESET 35
[7]
M2
[7]
I external reset input: A LOW on this pin resets the device, causing I/O
ports and peripherals to take on their default states, and processor
execution to begin at address 0. TTL with hysteresis, 5 V tolerant.
XTAL1 44
[8][9]
M4
[8][9]
I Input to the oscillator circuit and internal clock generator circuits.
XTAL2 46
[8][9]
N4
[8][9]
O Output from the oscillator amplifier.
RTCX1 34
[8][10]
K2
[8][10]
I Input to the RTC oscillator circuit.
RTCX2 36
[8][10]
L2
[8][10]
O Output from the RTC oscillator circuit.
V
SSIO
33, 63,
77, 93,
114,
133,
148,
169,
189,
200
[11]
L3, T5,
R9, P12,
N16,
H14,
E15,
A12, B6,
A2
[11]
I ground: 0 V reference for the digital IO pins.
V
SSCORE
32, 84,
172
[11]
K4, P10,
D12
[11]
I ground: 0 V reference for the core.
V
SSA
22
[12]
J2
[12]
I analog ground: 0 V reference. This should nominally be the same
voltage as V
SSIO
/V
SSCORE
, but should be isolated to minimize noise and
error.
V
DD(3V3)
15, 60,
71, 89,
112,
125,
146,
165,
181,
198
[13]
G3, P6,
P8, U13,
P17,
K16,
C17,
B13, C9,
D7
[13]
I 3.3 V supply voltage: This is the power supply voltage for the I/O ports.
n.c. 30, 117,
141
[14]
J4, L14,
G14
[14]
I not connected pins: These pins must be left unconnected (floating).
V
DD(DCDC)(3V3)
26, 86,
174
[15]
H4, P11,
D11
[15]
I 3.3 V DC-to-DC converter supply voltage: This is the power supply for
the on-chip DC-to-DC converter.
V
DDA
20
[16]
G4
[16]
I analog 3.3 V pad supply voltage: This should be nominally the same
voltage as V
DD(3V3)
but should be isolated to minimize noise and error.
This voltage is used to power the ADC and DAC.
VREF 24
[16]
K1
[16]
I ADC reference: This should be nominally the same voltage as V
DD(3V3)
but should be isolated to minimize noise and error. The level on this pin is
used as a reference for ADC and DAC.
VBAT 38
[16]
M3
[16]
I RTC power supply: 3.3 V on this pin supplies the power to the RTC
peripheral.
Table 4. Pin description
…continued
Symbol Pin Ball Type Description