EP1M350 datasheet(53/86 Pages) ALTERA

53 / 86 page

Altera Corporation

Mercury Programmable Logic Device Family Data Sheet

Open-Drain Output

Mercury devices provide an optional open-drain (equivalent to an open-

collector) output for each I/O pin. This open-drain output enables the

device to provide system-level control signals (e.g., interrupt and write

enable signals) that can be asserted by any of several devices.

Slew-Rate Control

The output buffer for each Mercury device I/O pin has a programmable

output slew rate control that can be configured for low-noise or high-

speed performance. A faster slew rate provides high-speed transitions for

high-performance systems. However, these fast transitions may introduce

noise transients into the system. A slow slew rate reduces system noise,

but adds a nominal delay to rising and falling edges. Each I/O pin has an

individual slew rate control, allowing the designer to specify the slew rate

on a pin-by-pin basis. The slew rate control affects both the rising and

falling edges.

Table 11. Programmable Drive Strength

I/O Standard

IOH/IOL Current Strength

Setting

LVTTL (3.3 V)

4 mA

8 mA

12 mA

16 mA

24 mA (default)

LVTTL (2.5 V)

4 mA

8 mA

12 mA

16 mA (default)

LVTTL (1.8 V)

2 mA

4 mA (default)

SSTL-3 class I and II

SSTL-2 class I and II

HSTL class I and II

GTL+ (3.3 V)

Minimum

Maximum (default)

EP1M350 Datasheet(PDF) 53 Page - Altera Corporation