Datasheet
LPC1759_58_56_54_52_51 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 8.5 — 24 June 2014 13 of 80
NXP Semiconductors
LPC1759/58/56/54/52/51
32-bit ARM Cortex-M3 microcontroller
[1] 5 V tolerant pad providing digital I/O functions with TTL levels and hysteresis. This pin is pulled up to a voltage level of 2.3 V to 2.6 V.
[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 and the pin is not 5 V tolerant. This pin is pulled up to a voltage level of 2.3 V to 2.6 V.
[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. This pin is pulled up to a voltage level of 2.3 V to 2.6 V.
[4] Pad provides digital I/O and USB functions. It is designed in accordance with the USB specification, revision 2.0 (Full-speed and
Low-speed mode only). This pad is not 5 V tolerant.
[5] 5 V tolerant pad with 10 ns glitch filter providing digital I/O functions with TTL levels and hysteresis. This pin is pulled up to a voltage
level of 2.3 V to 2.6 V.
[6] 5 V tolerant pad with TTL levels and hysteresis. Internal pull-up and pull-down resistors disabled.
[7] 5 V tolerant pad with TTL levels and hysteresis and internal pull-up resistor.
[8] 5 V tolerant pad with 20 ns glitch filter providing digital I/O function with TTL levels and hysteresis.
[9] Pad provides special analog functionality. 32 kHz crystal oscillator must be used with the RTC.
[10] When the system oscillator is not used, connect XTAL1 and XTAL2 as follows: XTAL1 can be left floating or can be grounded (grounding
is preferred to reduce susceptibility to noise). XTAL2 should be left floating.
[11] When the RTC is not used, connect VBAT to V
DD(REG)(3V3)
and leave RTCX1 floating.
XTAL1 19
[9][10]
I Input to the oscillator circuit and internal clock generator circuits.
XTAL2 20
[9][10]
O Output from the oscillator amplifier.
RTCX1 13
[9][11]
I Input to the RTC oscillator circuit.
RTCX2 15
[9]
O Output from the RTC oscillator circuit.
V
SS
24, 33,
43, 57,
66, 78
I ground: 0 V reference.
V
SSA
9Ianalog ground: 0 V reference. This should nominally be the same voltage as V
SS
,
but should be isolated to minimize noise and error.
V
DD(3V3)
21, 42,
56, 77
I 3.3 V supply voltage: This is the power supply voltage for the I/O ports.
V
DD(REG)(3V3)
34, 67 I 3.3 V voltage regulator supply voltage: This is the supply voltage for the on-chip
voltage regulator only.
V
DDA
8Ianalog 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. This pin should be tied to 3.3 V if the ADC and DAC are
not used.
VREFP 10 I ADC positive reference voltage: This should be nominally the same voltage as
V
DDA
but should be isolated to minimize noise and error. Level on this pin is used
as a reference for ADC and DAC. This pin should be tied to 3.3 V if the ADC and
DAC are not used.
VREFN 12 I ADC negative reference voltage: This should be nominally the same voltage as
V
SS
but should be isolated to minimize noise and error. Level on this pin is used as
a reference for ADC and DAC.
VBAT 16
[11]
I RTC pin power supply: 3.3 V on this pin supplies the power to the RTC
peripheral.
Table 4. Pin description …continued
Symbol Pin Type Description