LPC2141_42_44_46_48_4

© NXP B.V. 2008. All rights reserved.

Product data sheet

Rev. 04 — 17 November 2008

11 of 40

NXP Semiconductors

LPC2141/42/44/46/48

Single-chip 16-bit/32-bit microcontrollers

[1]

5 V tolerant pad (no built-in pull-up resistor) providing digital I/O functions with TTL levels and hysteresis and 10 ns slew rate control.

[2]

5 V tolerant pad (no built-in pull-up resistor) providing digital I/O functions with TTL levels and hysteresis and 10 ns slew rate control. If

configured for an input function, this pad utilizes built-in glitch filter that blocks pulses shorter than 3 ns.

[3]

functionality.

P1.26/RTCK

24[6]

I/O

P1.26 — General purpose input/output digital pin (GPIO).

I/O

RTCK — Returned Test Clock output. Extra signal added to the JTAG port.

Assists debugger synchronization when processor frequency varies.

Bidirectional pin with internal pull-up.

Note: LOW on RTCK while RESET is LOW enables pins P1.31:26 to operate

as Debug port after reset.

P1.27/TDO

64[6]

I/O

P1.27 — General purpose input/output digital pin (GPIO).

O

TDO — Test Data out for JTAG interface.

P1.28/TDI

60[6]

I/O

P1.28 — General purpose input/output digital pin (GPIO).

I

TDI — Test Data in for JTAG interface.

P1.29/TCK

56[6]

I/O

P1.29 — General purpose input/output digital pin (GPIO).

I

⁄

the CPU clock (CCLK) for the JTAG interface to operate.

P1.30/TMS

52[6]

I/O

P1.30 — General purpose input/output digital pin (GPIO).

I

TMS — Test Mode Select for JTAG interface.

P1.31/TRST

20[6]

I/O

P1.31 — General purpose input/output digital pin (GPIO).

I

TRST — Test Reset for JTAG interface.

D+

10[7]

I/O

USB bidirectional D+ line.

D

−

11[7]

I/O

USB bidirectional D

− line.

RESET

57[8]

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

62[9]

I

Input to the oscillator circuit and internal clock generator circuits.

XTAL2

61[9]

O

Output from the oscillator amplifier.

RTCX1

3[9]

I

Input to the RTC oscillator circuit.

RTCX2

5[9]

O

Output from the RTC oscillator circuit.

6, 18, 25, 42,

50

I

Ground: 0 V reference.

59

I

Analog ground: 0 V reference. This should nominally be the same voltage

23, 43, 51

I

3.3 V power supply: This is the power supply voltage for the core and I/O

ports.

7I

Analog 3.3 V power supply: This should be nominally the same voltage as

used to power the on-chip ADC(s) and DAC.

VREF

63

I

ADC reference voltage: This should be nominally less than or equal to the

pin is used as a reference for ADC(s) and DAC.

VBAT

49

I

RTC power supply voltage: 3.3 V on this pin supplies the power to the RTC.

Table 3.

Symbol

Pin

Type

Description