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AS1121

Datasheet - Detailed Descr i pti on

OUTn Enable

All OUTn channels can be collectively switched off with one signal. When OEN is set to 1, all OUTn channels are disabled, regardless of the

device logic operations. The greyscale counter is also reset when OEN is set to 1.

When OEN is set to 0, all OUTn channels are in normal operation.

Setting Maximum Channel Current

multiplied by a factor of 31.5. The maximum output current is calculated as:

Where:

Power Dissipation

To ensure proper operation of the device, the total power dissipation of the AS1121 must be below the power dissipation rating of the device

package. Total power dissipation is calculated as:

Where:

DCn is the maximum dot correction value for OUTn;

n is the number of OUTn driving LED at the same time;

Operating Modes

The AS1121 operates in two modes (see Table 8). Greyscale operating mode (see Figure 22 on page 14) and the shift registers are in reset state

at power-up.

Table 7. Pin OEN Truth Table

OEN

OUT0:OUT15

0

Normal Operation

1Disabled

Table 8. Operating Modes

Mode

Input Shift Register

Operating Mode

0

192-bit

Greyscale PWM Mode

1

96-bit

Dot Correction Data Input Mode

x 31.5

(EQ 1)

DCn

63

(EQ 2)