# HT74LS247ARZ

**HTCSEMI** · Buffers, Drivers, Receivers, Transceivers · SOP-16

HT74LS247ARZ from HTCSEMI, in a SOP-16. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | B | input | BCD input B; VIH min 2.0 V, VIL max 0.8 V. |
| 2 | C | input | BCD input C; VIH min 2.0 V, VIL max 0.8 V. |
| 3 | LT | input | Active-low lamp test input; with BI/RBO open or high, a low on LT turns all segment outputs on. |
| 4 | BI/RBO | bidirectional | Blanking input or ripple-blanking output (wire-AND); a low on BI turns all segments off, output rated IOH -50 µA and IOL 3.2 mA. |
| 5 | RBI | input | Ripple-blanking input; must be open or high if blanking of a decimal zero is not desired. |
| 6 | D | input | BCD input D (MSB); VIH min 2.0 V, VIL max 0.8 V. |
| 7 | A | input | BCD input A (LSB); VIH min 2.0 V, VIL max 0.8 V. |
| 8 | GND | power_in | Ground. |
| 9 | e | output | Active-low open-collector segment e output; sinks up to 24 mA, off-state voltage up to 15 V. |
| 10 | d | output | Active-low open-collector segment d output; sinks up to 24 mA, off-state voltage up to 15 V. |
| 11 | c | output | Active-low open-collector segment c output; sinks up to 24 mA, off-state voltage up to 15 V. |
| 12 | b | output | Active-low open-collector segment b output; sinks up to 24 mA, off-state voltage up to 15 V. |
| 13 | a | output | Active-low open-collector segment a output; sinks up to 24 mA, off-state voltage up to 15 V. |
| 14 | g | output | Active-low open-collector segment g output; sinks up to 24 mA, off-state voltage up to 15 V. |
| 15 | f | output | Active-low open-collector segment f output; sinks up to 24 mA, off-state voltage up to 15 V. |
| 16 | VCC | power_in | Supply voltage, 4.75 V to 5.25 V (5.0 V typical). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | HTCSEMI |
| Package | SOP-16 |
| Category | Logic |
| Pins | 16 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Supply Voltage | VCC | 4.75 | 5 | 5.25 | V |  | 1 |
| Operating Ambient Temperature Range | TA | 0 | 25 | 70 | °C |  | 1 |
| Output Current, High BI/RBO | IOH |  |  | -50 | µA | BI/RBO | 1 |
| Output Current, Low BI/RBO | IOL |  |  | 3.2 | mA | BI/RBO | 1 |
| Off-State Output Voltage a-g | VO(off) |  |  | 15 | V | a, g | 1 |
| On-State Output Current a-g | IO(on) |  |  | 24 | mA | a, g | 1 |
| Input HIGH Voltage | VIH | 2 |  |  | V | Guaranteed Input HIGH Voltage for All Inputs | 5 |
| Input LOW Voltage | VIL |  |  | 0.8 | V | Guaranteed Input LOW Voltage for All Inputs | 5 |
| Input Clamp Diode Voltage | VIK |  | -0.65 | -1.5 | V | VCC = MIN, IIN = -18 mA | 5 |
| Output HIGH Voltage BI/RBO | VOH | 2.4 | 4.2 |  | V | VCC = MIN, IOH = MAX, VIN = VIH or VIL per Truth Table | 5 |
| Output LOW Voltage BI/RBO | VOL |  | 0.25 | 0.4 | V | IOL = 1.6 mA, VCC = VCC MIN, VIN = VIL or VIH | 5 |
| Output LOW Voltage BI/RBO | VOL |  | 0.35 | 0.5 | V | IOL = 3.2 mA | 5 |
| Off-State Output Current a-g | IO(off) |  |  | 250 | µA | VCC = MAX, VIH = 2.0 V, VO(off) = 15 V, VIL = MAX | 5 |
| On-State Output Voltage a-g | VO(on) |  | 0.25 | 0.4 | V | IO(on) = 12 mA, VCC = MIN, VIH = 2.0 V | 5 |
| On-State Output Voltage a-g | VO(on) |  | 0.35 | 0.5 | V | IO(on) = 24 mA | 5 |
| Input HIGH Current | IIH |  |  | 20 | µA | VCC = MAX, VIN = 2.7 V | 5 |
| Input HIGH Current | IIH |  |  | 0.1 | mA | VCC = MAX, VIN = 7.0 V | 5 |
| Input LOW Current, any input except BI/RBO | IIL |  |  | -0.4 | mA | VCC = MAX, VIN = 0.4 V | 5 |
| Input LOW Current BI/RBO | IIL |  |  | -1.2 | mA | VCC = MAX, VIN = 0.4 V | 5 |
| Short Circuit Current BI/RBO | IOS | -0.3 |  | -2 | mA | VCC = MAX, Note 1 | 5 |
| Power Supply Current | ICC |  | 7 | 13 | mA | VCC = MAX | 5 |
| Turn-Off/Turn-On Time from A Input | tPLH/tPHL |  |  | 100 | ns | VCC = 5.0 V, TA = 25°C, CL = 15 pF, RL = 665 Ω | 5 |
| Turn-Off/Turn-On Time from RBI Input | tPHL/tPLH |  |  | 100 | ns | VCC = 5.0 V, TA = 25°C, CL = 15 pF, RL = 665 Ω | 5 |

## CAD (KiCad official)

- Symbol: `HT74LS247ARZ`
- Footprint: `Package_SO:SOIC-16_3.9x9.9mm_P1.27mm`
- 3D model: SOP-16 (KiCad packages3D, STEP)
- 3D model files: `ht74ls247arz-etched.step` / `ht74ls247arz-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ht74ls247arz.step` / `ht74ls247arz.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [HTCSEMI datasheet](docs/ht74ls247arz-datasheet.pdf) (7 pp, sha256 `75e82e17e30d5eb5`, retrieved 2026-10-27, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/ht74ls247arz-datasheet.pdf)