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74HC/HCT646
General description
The 74HC/HCT646 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A.
The 74HC/HCT646 consist of bus transceiver circuits with 3-state outputs, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the internal registers. Data on the 'A' or 'B' bus will be clocked into the registers as the appropriate clock (CPAB and CPBA) goes to a HIGH logic level. Output enable (OE) and direction (DIR) inputs are provided to control the transceiver function. In the transceiver mode, data present at the high-impedance port may be stored in either the 'A' or 'B' register, or in both. The select source inputs (SAB and SBA) can multiplex stored and real-time (transparent mode) data. The direction (DIR) input determines which bus will receive data when OE is active (LOW). In the isolation mode (OE = HIGH), 'A' data may be stored in the 'B' register and/or 'B' data may be stored in the 'A' register.
When an output function is disabled, the input function is still enabled and may be used to store and transmit data. Only one of the two buses, A or B, may be driven at a time.
The '646' is functionally identical to the '648', but has non-inverting data paths.
Features
- Independent register for A and B buses
- Multiplexed real-time and stored data
- Output capability: bus driver
- ICC category: MSI
Products/packages
| Type number | North American Type number | Ordering code (12NC) | Product status | Package | Packing | Marking | Chemical content | Leadfree conversion date |
|---|---|---|---|---|---|---|---|---|
| 74HC646D | 74HC646D | 9337 155 30652 | Volume production | SOT137-1
(SO24) | Bulk Pack, CECC | Standard Marking | 74HC646D
| week 6, 2005 |
| 74HC646D | 74HC646D-T | 9337 155 30653 | Volume production | SOT137-1
(SO24) | Reel Pack, SMD, 13", CECC | Standard Marking | 74HC646D
| week 6, 2005 |
| 74HC646DB | 74HC646DB | 9351 894 20112 | Volume production | SOT340-1
(SSOP24) | Tube | Standard Marking | 74HC646DB
| week 12, 2005 |
| 74HC646DB | 74HC646DB-T | 9351 894 20118 | Volume production | SOT340-1
(SSOP24) | Reel Pack, SMD, 13" | Standard Marking | 74HC646DB
| week 12, 2005 |
| 74HC646N | 74HC646N | 9336 707 40652 | Volume production | SOT101-1
(DIP24) | Bulk Pack, CECC | Standard Marking | 74HC646N
| Always Pb-free |
| 74HCT646D | 74HCT646D | 9337 156 40652 | Volume production | SOT137-1
(SO24) | Bulk Pack, CECC | Standard Marking | 74HCT646D
| week 6, 2005 |
| 74HCT646D | 74HCT646D-T | 9337 156 40653 | Volume production | SOT137-1
(SO24) | Reel Pack, SMD, 13", CECC | Standard Marking | 74HCT646D
| week 6, 2005 |
| 74HCT646DB | 74HCT646DB | 9351 902 10112 | Volume production | SOT340-1
(SSOP24) | Tube | Standard Marking | 74HCT646DB
| week 12, 2005 |
| 74HCT646DB | 74HCT646DB-T | 9351 902 10118 | Volume production | SOT340-1
(SSOP24) | Reel Pack, SMD, 13" | Standard Marking | 74HCT646DB
| week 12, 2005 |
| 74HCT646N | 74HCT646N | 9336 709 90652 | Volume production | SOT101-1
(DIP24) | Bulk Pack, CECC | Standard Marking | 74HCT646N
| Always Pb-free |
Pricing/ordering/availability
| Type number | Ordering code(12NC) | Indicative price/unit($) | Region | Distributor | In stock | Inventory date | Buy online | Samples |
|---|---|---|---|---|---|---|---|---|
| 74HC646D | 9337 155 30652 | 1.1500 | not available | |||||
| 74HC646D | 9337 155 30653 | 1.1500 | Order samples | |||||
| 74HC646DB | 9351 894 20112 | 1.1500 | NA | DIGI-KEY CORPORATION | 801 | 6/29/2008 | Buy online | not available |
| 74HC646DB | 9351 894 20118 | 1.1500 | Order samples | |||||
| 74HC646N | 9336 707 40652 | 1.2600 | NA | FUTURE ELECTRONICS | 570 | 7/4/2008 | Buy online | Order samples |
| 74HCT646D | 9337 156 40652 | 1.1500 | not available | |||||
| 74HCT646D | 9337 156 40653 | 1.1500 | Order samples | |||||
| 74HCT646DB | 9351 902 10112 | 1.1500 | NA | DIGI-KEY CORPORATION | 821 | 6/29/2008 | Buy online | not available |
| 74HCT646DB | 9351 902 10118 | 1.1500 | Order samples | |||||
| 74HCT646N | 9336 709 90652 | 1.2600 | Order samples |
Parametrics/similar products
| Type number | Package | Description | Fmax(MHz) | Propagation Delay(ns) | Voltage | No. of Pins | Power Dissipation Considerations | Logic Switching Levels | Output Drive Capability |
|---|---|---|---|---|---|---|---|---|---|
| 74HC646D | SOT137-1
(SO24) | Transceiver/Register (3-State) | 75 @ 6 V | 11@5V | 2.0-6.0 V | 24 | Low Power or Battery Applications | CMOS | +/- 7.8 mA |
| 74HC646DB | SOT340-1
(SSOP24) | Transceiver/Register (3-State) | 75 @ 6 V | 11@5V | 2.0-6.0 V | 24 | Low Power or Battery Applications | CMOS | +/- 7.8 mA |
| 74HC646N | SOT101-1
(DIP24) | Transceiver/Register (3-State) | 75 @ 6 V | 11@5V | 2.0-6.0 V | 24 | Low Power or Battery Applications | CMOS | +/- 7.8 mA |
| 74HCT646D | SOT137-1
(SO24) | Transceiver/Register; TTL Enabled (3-State) | 85 | 13 | 4.5-5.5 V | 24 | Low Power | TTL | +/- 6 mA |
| 74HCT646DB | SOT340-1
(SSOP24) | Transceiver/Register; TTL Enabled (3-State) | 85 | 13 | 4.5-5.5 V | 24 | Low Power | TTL | +/- 6 mA |
| 74HCT646N | SOT101-1
(DIP24) | Transceiver/Register; TTL Enabled (3-State) | 85 | 13 | 4.5-5.5 V | 24 | Low Power | TTL | +/- 6 mA |
Similar products
74HC/HCT646 links to the similar products page containing an overview of products that are similar in function or related to the type number(s) as listed on this page. The similar products page includes products from the same catalog tree(s), relevant selection guides and products from the same functional category.
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