16

Altera Corporation

Configuration Devices for SRAM-based LUT Devices Data Sheet

Notes to

Figure 6:

(1)

Do not use EPC2 devices to configure FLEX 6000 devices.

(2)

The pull-up resistor should be connected to the same supply voltage as the configuration device. All pull-up

resistors are 1 k

Ω (APEX 20KE pull-resistors are 10 kΩ). The OE and nCS pins on EPC2 devices have internal, user-

configurable 1-k

Ω pull-up resistors. If internal pull-up resistors are used, external pull-up resistors should not be

used on these pins. The Quartus II software uses the internal pull-up resistors by default. To turn off the internal

pull-up resistors, check the Disable nCS and OE pull-ups on configuration device option when generating programming

files.

(3)

The diagram shows an APEX II, APEX 20K, Mercury, ACEX 1K, or FLEX 10K device, which has MSEL0 and MSEL1

tied to ground. For FLEX 6000 devices, MSEL is tied to ground, and the DATA0 pin is named DATA. EPC2 cannot be

used with FLEX 6000 devices. All other connections are the same for FLEX 6000 devices.

(4)

EPC4, EPC8, and EPC16 devices cannot be cascaded.

(5)

The nINIT_CONF pin is only available on EPC2 devices and has an internal pull up of 1 k

Ω that is always active. If

nINIT_CONF

(6)

To ensure successful configuration between APEX 20KE and configuration devices in all possible power-up

(7)

This diagram is for APEX 20KE devices only.

(8)

To isolate the 1.8-V and 3.3-V power supplies when configuration APEX 20KE devices, add a diode between the

APEX 20KE device’s nCONFIG pin and the configuration device’s nINIT_CONF pin. Select a diode with a threshold

only be able to drive low or tri-state.

device configuration, see Application Note 116 (Configuring ACEX 1K,

APEX 20K, FLEX 10K & FLEX 6000 Devices).

Figure 7 shows the timing waveform for the configuration device scheme.

Figure 7. Configuration Device Scheme Timing Waveform

Notes to

Figure 7:

(1)

The configuration devivce will drive DATA low after configuration.

(2)

APEX II and APEX 20K devices (except EP2A70 devices) enter user mode 40 clock cycles after CONF_DONE goes

high. EP2A70 devices enter user mode 72 clock cycles after CONF_DONE goes high. FLEX 10K and FLEX 6000 devices

enter user mode 10 clock cycles after CONF_DONE goes high. Mercury devices enter user mode 136 clock cycles after

CONF_DONE

goes high.

DD

D

D

0

1

2

3

Tri-State

User Mode

(2)

(1)

Tri-State

OE/nSTATUS

nCS/CONF_DONE

DCLK

DATA

User I/O

INIT_DONE

nINIT_CONF or VCC/nCONFIG