The DM7446A and DM7447A feature active-LOW outputs designed for driving common-anode LEDs or incandescent indicators directly. All of the circuits have full ripple-blanking input/output controls and a lamp test input. Segment identification and resultant displays are shown on a following page. Display patterns for BCD input counts above nine are unique symbols to authenticate input conditions. All of the circuits incorporate automatic leading and/or trailing-edge, zero-blanking control (RBI and RBO). Lamp test (LT) of these devices may be performed at any time when the BI/RBO node at a HIGH logic level. All types contain an overriding blanking input (BI) which can be used to control the lamp intensity (by pulsing) or to inhibit the outputs.
s All circuit types feature lamp intensity modulation capability s Open-collector outputs drive indicators directly s Lamp-test provision s Leading/trailing zero suppression
Order Number DM7446AN DM7447AN Package Number N16E Package Description 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide
Note 1: BI/RBO is a wire-AND logic serving as blanking input (BI) and/or ripple-blanking output (RBO). Note 2: The blanking input (BI) must be OPEN or held at a HIGH logic level when output functions 0 through 15 are desired. The ripple-blanking input (RBI) must be OPEN or HIGH if blanking of a decimal zero is not desired. Note 3: When a LOW logic level is applied directly to the blanking input (BI), all segment outputs are HIGH regardless of the level of any other input. Note 4: When ripple-blanking input (RBI) and inputs B, C, and D are at a LOW level with the lamp test input HIGH, all segment outputs go H and the ripple-blanking output (RBO) goes to a LOW level (response condition). Note 5: When the blanking input/ripple-blanking output (BI/RBO) is OPEN or held HIGH and a LOW is applied to the lamp-test input, all segment outputs are L.
Supply Voltage Input Voltage Operating Free Air Temperature Range Storage Temperature Range to +70°C
Note 6: The "Absolute Maximum Ratings" are those values beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed at the absolute maximum ratings. The "Recommended Operating Conditions" table will define the conditions for actual device operation.
Symbol DM7446A VCC VIH VIL VOH IOH IOL TA DM7447A VCC VIH VIL VOH IOH IOL TA Supply Voltage HIGH Level Input Voltage LOW Level Input Voltage HIGH Level Output Voltage (a thru g) HIGH Level Output Current (BI/RBO) LOW Level Output Current (a thru g) LOW Level Output Current (BI/RBO) Free Air Operating Temperature Supply Voltage HIGH Level Input Voltage LOW Level Input Voltage HIGH Level Output Voltage (a thru g) HIGH Level Output Current (BI/RBO) LOW Level Output Current (a thru g) LOW Level Output Current (BI/RBO) Free Air Operating Temperature Parameter Min Nom Max Units