Interfacing and Operation
Control Basics
Power Requirements
The
Table 6. Input Power
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| Symbol | Min | Typ | Max | Units |
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Backlight |
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Backlight voltage |
| VH | +10.8 | +12.0 | +13.2 | Vdc |
Absolute max. voltage |
| VHMAX | 0 | – | +16 | Vdc |
Steady state current (VH = | +12 Vdc) | IH | – | 1.9 | 2.5 | Adc |
Peak | +12 Vdc) | IHSU | – | – | 3.5 | Adc |
Power (VH = +12V) |
| PH | – | 23 | 30 | W |
LCD |
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LCD voltage |
| VL | 4.5 | +5.0 | +5.5 | Vdc |
Absolute max. voltage |
| VLMAX | 0 | – | 6.0 | Vdc |
VL permissible ripple (VL = +5V) | ΔVL | – | – | 100 | mVpp | |
Current (VL = +5V) |
| IL | – | 280 | 450 | mAdc |
Power (VL = +5V) |
| PL | – | 1.4 | 2.3 | W |
CAUTION: Absolute maximum ratings are those values beyond which damage to the device may occur.
Undervoltage Lockout (Backlight only)
An undervoltage lockout (UVLO) function is included which disables the backlight under excessively low VH conditions. The UVLO circuit will disable the backlight at approximately +8.5 Vdc as VH falls and will enable the backlight at approximately +9.5 Vdc as VH rises.
Power Sequencing (LCD only)
Certain restrictions on the behavior of the VL (+5 Vdc) source and in the application of the VL source relative to the application or removal of the video signals must be observed. These restrictions are shown in Figure 2, where “Vcc”= VL and “data” = video signals.
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