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74ABT657
Datasheet
(Product Specification)
27-Oct-04, 14 pages, 139 kB
General description
The 74ABT657 high-performance BiCMOS device combines low static and dynamic power dissipation with high speed and high output drive.
The 74ABT657 is an octal transceiver featuring non-inverting buffers with 3-State outputs and an 8-bit parity generator/checker, and is intended for bus-oriented applications. The buffers have a guaranteed current sinking capability of 64 mA. The Transmit/Receive (T/R) input determines the direction of the data flow through the bidirectional transceivers. Transmit (active-HIGH) enables data from A ports to B ports; Receive (active-LOW) enables data from B ports to A ports.
The Output Enable (OE) input disables both the A and B ports by placing them in a high-impedance condition when the OE input is HIGH. The parity select (ODD/EVEN) input gives the user the option of odd or even parity systems. The parity (PARITY) pin is an output from the generator/checker when transmitting from the port A to B (T/R = HIGH) and an input when receiving from port B to A port (T/R = Low). When transmitting (T/R = HIGH) the parity select (ODD/EVEN) input is set, then the A port data is polled to determine the number of HIGH bits. The parity (PARITY) output then goes to the logic state determined by the parity select (ODD/EVEN) setting and by the number of HIGH bits on port A. For example, if the parity select (ODD/EVEN) is set LOW (even parity), and the number of HIGH bits on port A is odd, then the parity (PARITY) output will be HIGH, transmitting even parity. If the number of HIGH bits on port A is even, then the parity (PARITY) output will be LOW, keeping even parity. When in receive mode (T/R = LOW) the B port is polled to determine the number of HIGH bits. If parity select (ODD/EVEN) is LOW (even parity) and the number of HIGHs on port B is:
- (1) odd and the parity (PARITY) input is HIGH, then ERROR will be
HIGH, signifying no error.
- (2) even and the parity (PARITY) input is HIGH, then ERROR will
be asserted LOW, indicating an error.
Features
- Combinational functions in one package
- Low static and dynamic power dissipation with high speed and high output drive
- Output capability: +64 mA/-32 mA
- Power-up 3-State
- Latch-up protection exceeds 500 mA per JEDEC Std 17
- ESD protection exceeds 2000 V per MIL STD 883 Method 3015 and 200 V per Machine Model
Products/packages
| Type number | Orderable part number | Ordering code (12NC) | Product status | Package | Packing | Marking | ECCN |
|---|---|---|---|---|---|---|---|
| 74ABT657D | 74ABT657D,602 | 9350 452 90602 | Volume production | SOT137 | Tube (Signetics) | Standard Marking | |
| 74ABT657D | 74ABT657D,623 | 9350 452 90623 | Volume production | SOT137 | Reel Pack, SMD, 13" (Signetics) | Standard Marking | |
| 74ABT657DB | 74ABT657DB,112 | 9350 691 80112 | Volume production | SOT340-1
(SSOP24) | Tube | Standard Marking | |
| 74ABT657DB | 74ABT657DB,118 | 9350 691 80118 | Volume production | SOT340-1
(SSOP24) | Reel Pack, SMD, 13" | Standard Marking | |
| 74ABT657PW | 74ABT657PW,112 | 9351 789 00112 | Volume production | SOT355-1
(TSSOP24) | Tube | Standard Marking | |
| 74ABT657PW | 74ABT657PW,118 | 9351 789 00118 | Volume production | SOT355-1
(TSSOP24) | Reel Pack, SMD, 13" | Standard Marking |
Quality/reliability/chemical content
| Type number | Orderable part number | Chemical content | RoHS | Leadfree Conversion date | RHF | IRF (FIT) | MTBF (hours) | MSL |
|---|---|---|---|---|---|---|---|---|
| 74ABT657D | 74ABT657D,602 | 74ABT657D |
| week 13, 2005 | 1,33 | 7,52E+08 | 1 | |
| 74ABT657D | 74ABT657D,623 | 74ABT657D |
| week 13, 2005 | 1,33 | 7,52E+08 | 1 | |
| 74ABT657DB | 74ABT657DB,112 | 74ABT657DB |
| week 12, 2005 | 1,33 | 7,52E+08 | 1 | |
| 74ABT657DB | 74ABT657DB,118 | 74ABT657DB |
| week 12, 2005 | 1,33 | 7,52E+08 | 1 | |
| 74ABT657PW | 74ABT657PW,112 | 74ABT657PW |
| week 10, 2005 | 1,33 | 7,52E+08 | 1 | |
| 74ABT657PW | 74ABT657PW,118 | 74ABT657PW |
| week 10, 2005 | 1,33 | 7,52E+08 | 1 |
Pricing/ordering/availability
| Type number | Ordering code(12NC) | Orderable part number | Indicative price/unit($) | Region | Distributor | In stock | Order quantity | Inventory date | Buy online | Samples |
|---|---|---|---|---|---|---|---|---|---|---|
| 74ABT657D | 9350 452 90602 | 74ABT657D,602 | 1.4900 | not available | ||||||
| 74ABT657D | 9350 452 90623 | 74ABT657D,623 | 1.4900 | not available | ||||||
| 74ABT657DB | 9350 691 80112 | 74ABT657DB,112 | 1.4900 | not available | ||||||
| 74ABT657DB | 9350 691 80118 | 74ABT657DB,118 | 1.4900 | not available | ||||||
| 74ABT657PW | 9351 789 00112 | 74ABT657PW,112 | 1.3000 | NA | FUTURE ELECTRONICS | 1,575 | 11/19/2009 | Buy online | not available | |
| 74ABT657PW | 9351 789 00118 | 74ABT657PW,118 | 1.3000 | not available |
Design support
Application Notes
AN203;
Test Fixtures for High Speed Logic (1998-04-02)
Support Documents
ABT_FUNCSELGD;
Functional selection guide ABT family (2004-08-13)Parametrics/similar products
| Type number | Package | Description | Propagation Delay(ns) | Voltage | Logic Switching Levels | Output Drive Capability |
|---|---|---|---|---|---|---|
| 74ABT657D | SOT137
| Octal Transceiver with Parity Generator/Checker; Non-Inverting (3-State) | 3.3 | 4.5-5.5 V | TTL | -32/+64 mA |
| 74ABT657DB | SOT340-1
(SSOP24) | Octal Transceiver with Parity Generator/Checker; Non-Inverting (3-State) | 3.3 | 4.5-5.5 V | TTL | -32/+64 mA |
| 74ABT657PW | SOT355-1
(TSSOP24) | Octal Transceiver with Parity Generator/Checker; Non-Inverting (3-State) | 3.3 | 4.5-5.5 V | TTL | -32/+64 mA |
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