74AVCH4T245 4-BIT DUAL POWER SUPPLY TRANSLATING BUFFER WITH 3-STATE OUTPUTS
Diodes Incorporated
Description
The 74AVCH4T245 device is a 4-bit, dual supply transceiver that enables bi-directional level translation, designed for asynchronous communication between two data buses. It features four 2-bit input-output ports (nAn and nBn), a direction control input (nDIR), an output enable input (nOE), and dual supply pins (VCCA and VCCB). Both VCCA and VCCB can be supplied at any voltage between 0.8V and 3.6V, making the device suitable for translating between any of the low voltage nodes (0.8V, 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V). Pins nAn, nOE, and nDIR are referenced to VCCA, and pins nBn are referenced to VCCB. A HIGH on nDIR allows transmission from nAn to nBn, and a LOW on nDIR allows transmission from nBn to nAn. The output enable input (nOE) can be used to disable the outputs, so the buses are effectively isolated. The device is fully specified for partial power-down applications using IOFF. The IOFF circuitry disables the output, preventing any damaging backflow current through the device when it is powered down. In suspend mode, when either VCCA or VCCB is at GND level, both nAn and nBn are in the high-impedance OFF-state. The 74AVCH4T245 has active bus hold circuitry, which is provided to hold unused or floating data inputs at a valid logic level. This feature eliminates the need for external pullup or pulldown resistors.
The 74AVCH4T245 is available in the TSSOP-16 package and is specified for operation from -40°C to +125°C among all supply voltages. The wide temperature ranges and high ESD tolerance facilitate its use in harsh applications.
Pin Assignments
Top View of the TSSOP-16 package:
- Pin 1: VCCA
- Pin 2: 1DIR
- Pin 3: 2DIR
- Pin 4: 1A1
- Pin 5: 1A2
- Pin 6: 2A1
- Pin 7: 2A2
- Pin 8: GND
- Pin 9: GND
- Pin 10: 2B2
- Pin 11: 2B1
- Pin 12: 1B2
- Pin 13: 1B1
- Pin 14: 2OE
- Pin 15: 1OE
- Pin 16: VCCB
Features
- Supply Voltage Range: VCCA/ VCCB: 0.8V to 3.6V
- Max Data Rates: 380Mbps (1.8V to 3.3V Translation), 200Mbps (<1.8V to 3.3V Translation), 200Mbps (Translate to 2.5V or 1.8V), 150Mbps (Translate to 1.5V), 100Mbps (Translate to 1.2V), 50Mbps (Translate to 0.8V-1.1V)
- High Drive Strength (±12mA at 3.3V)
- IOFF Supports Partial-Power-Down Mode Operation
- ESD Protection Exceeds JESD 22
- Latchup Exceeds 100mA per JESD 78, Class II
- Totally Lead-Free & Fully RoHS Compliant
- Halogen and Antimony Free. "Green" Device
- For automotive applications requiring specific change control (i.e. parts qualified to AEC-Q100/101/104/200, PPAP capable, and manufactured in IATF 16949 certified facilities), please contact Diodes Incorporated or your local Diodes representative. See diodes.com/quality/product-definitions/ for more information.
Applications
- Personal electronics
- Industrial
- Enterprises
- Telecoms
Pin Descriptions
| Pin Name | Pin Number | Function |
|---|---|---|
| VCCA | 1 | A Port Supply Voltage |
| 1DIR | 2 | Direction Control Pin for Port "1" |
| 2DIR | 3 | Direction Control Pin for Port "2" |
| 1A1 | 4 | Input/Output 1A1. Referenced to VCCA. |
| 1A2 | 5 | Input/Output 1A2. Referenced to VCCA. |
| 2A1 | 6 | Input/Output 2A1. Referenced to VCCA. |
| 2A2 | 7 | Input/Output 2A2. Referenced to VCCA. |
| GND | 8 | Ground |
| GND | 9 | Ground |
| 2B2 | 10 | Input/Output 2B2. Referenced to VCCB. |
| 2B1 | 11 | Input/Output 2B1. Referenced to VCCB. |
| 1B2 | 12 | Input/Output 1B2. Referenced to VCCB. |
| 1B1 | 13 | Input/Output 1B1. Referenced to VCCB. |
| 2OE | 14 | 3-State Output-Mode Enable. Pull High for high-impedance mode for port "2". Referenced to VCCA. |
| 1OE | 15 | 3-State Output-Mode Enable. Pull High for high-impedance mode for port "1". Referenced to VCCA. |
| VCCB | 16 | B Port Supply Voltage |
Function Table
| OE | DIR | A Port | B Port | Operation |
|---|---|---|---|---|
| L | L | Enabled | Hi-Z | B to A |
| L | H | Hi-Z | Enabled | A to B |
| H | X | Hi-Z | Hi-Z | Isolation |
Note 4: Floating input pin is allowed for this case.
Logic Diagram
The logic diagram illustrates the internal circuitry of the 74AVCH4T245. It shows input signals like DIR and OE controlling NAND gates and buffers that drive the outputs A1, B1, A2, B2. The diagram depicts the transceiver's logic flow for data transmission and output enabling.
Electrical Characteristics
Absolute Maximum Ratings
| Symbol | Parameter | Rating | Unit |
|---|---|---|---|
| VCCA, VCCB | Supply Voltage Range | -0.5 to +4.6 | V |
| Vi | Input Voltage Range | -0.5 to +4.6 | V |
| Vo | Voltage Applied to Output in High or Low State | -0.5 to VCCO+0.5 | V |
| TJ | Operating Junction Temperature | +150 | °C |
| TSTG | Storage Temperature | -65 to +150 | °C |
Note 5: Stresses greater than those listed under Absolute Maximum Ratings can cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions is not implied. Exposure to Absolute Maximum Ratings for extended periods can affect device reliability.
Recommended Operating Conditions
| Symbol | Parameter | VCCA/VCCB Min | VCCA/VCCB Max | Unit |
|---|---|---|---|---|
| VCCA, VCCB | Operating Voltage | 0.8 | 3.6 | V |
| TA | Operating Free-Air Temperature | -40 | +125 | °C |
Note 8: All unused data inputs of the device must be held at VCCI or GND to ensure proper device operation.
Key Electrical Characteristics (Typical Values)
Note: Detailed specifications are provided in the full datasheet. The following are key parameters.
| Parameter | Test Conditions | Typical Value | Unit |
|---|---|---|---|
| VIH (High-Level Input Voltage) | VCC=0.8V | 0.70VCCI | V |
| VIL (Low-Level Input Voltage) | VCC=0.8V | 0.30VCCI | V |
| VOH (High-Level Output Voltage) | IOH = -3mA, VCC=1.1V | 0.95 | V |
| VOL (Low-Level Output Voltage) | IOL = 3mA, VCC=1.1V | 0.25 | V |
| Supply Current (ICCA/CCB) | VI = VCCI or GND, IO = 0 | ±1 (Typ) | µA |
Switching Characteristics
Note: Switching characteristics vary with supply voltage and temperature. The following are representative values.
| Parameter | Direction | VCCA=0.8V, VCCB=0.8V (Typ) | VCCA=3.3V, VCCB=3.3V (Typ) | Unit |
|---|---|---|---|---|
| Propagation Delay (tpd) | nAn to nBn | 11.0 | 2.9 | ns |
| nBn to nAn | 11.0 | 2.8 | ns | |
| Enable Time (ten) | nOE to nAn | 18.2 | 3.8 | ns |
| nOE to nBn | 19.2 | 3.8 | ns | |
| Disable Time (tdis) | nOE to nAn | 14.3 | 6.6 | ns |
| nOE to nBn | 12.6 | 6.2 | ns |
Parameter Measurement Information
The datasheet provides diagrams illustrating voltage waveforms for pulse duration, propagation delay, and enable/disable times. These measurements are performed using specific load circuits and test conditions, including specified load resistance (RL), capacitance (CL), and voltage thresholds (VTP).
Load Circuit and Voltage Waveforms
| Parameter | S1 | VCC | RL | CL | VTP |
|---|---|---|---|---|---|
| tpd | Open | 0.8V-1.6V | 2kΩ | 15pF | 0.1V |
| ten/tdis | 2*VCCO | 1.65V-2.7V | 2kΩ | 15pF | 0.15V |
| ten/tdis | GND | 3.0V-3.6V | 2kΩ | 15pF | 0.3V |
Notes: tPLH and tPHL are equivalent to tpd. Rise and fall times (tr, tf) are less than 1ns.
Ordering Information
The part number, such as 74AVCH4T245T16-13, indicates the device logic prefix (74AVCH), channel count (4T), function (245 Bus Transceiver), package type (T16 for TSSOP-16), and packing (13 for 13" Tape & Reel).
| Orderable Part Number | Package Code | Package | Qty. | Carrier |
|---|---|---|---|---|
| 74AVCH4T245T16-13 | T16 | TSSOP-16 | 2500 | Tape & Reel |
Refer to Diodes Incorporated's website for detailed packaging and pad layout information.
Marking Information
The TSSOP-16 package is marked with the Diodes logo, an Identification Code (AVCH4T245), and date codes (YY WW XX), where YY represents the year, WW represents the week, and XX is an internal code.
Package Outline Dimensions
TSSOP-16 Dimensions
| Dim | Min | Max | Typ | Unit | |
|---|---|---|---|---|---|
| A | - | 1.08 | - | mm | |
| A1 | 0.05 | 0.15 | - | mm | |
| A2 | 0.80 | 0.93 | - | mm | |
| b | 0.19 | 0.30 | - | mm | |
| c | 0.09 | 0.20 | - | mm | |
| D | 4.90 | 5.10 | - | mm | |
| E | - | 6.40 | BSC | mm | |
| E1 | 4.30 | 4.50 | - | mm | |
| e | - | - | 0.65 | BSC | mm |
| L | 0.45 | 0.75 | - | mm | |
| L1 | - | 1.00 | REF | mm | |
| L2 | - | 0.25 | BSC | mm | |
| R/R1 | 0.09 | - | - | mm | |
| X | - | - | 1.350 | mm | |
| Y | - | - | 1.050 | mm | |
| θ | 0° | 8° | - | - | |
| θ1 | 5° | 15° | - | - | |
| θ2 | 0° | - | - | - | |
| All Dimensions in mm | |||||
Suggested Pad Layout (TSSOP-16)
| Dimensions | Value (in mm) |
|---|---|
| C | 0.650 |
| X | 0.350 |
| X1 | 4.900 |
| Y | 1.400 |
| Y1 | 6.800 |
Mechanical Data
- Moisture Sensitivity: Level 1 per J-STD-020
- Terminals: Finish - Mate Tin Plated Leads, Solderable per MIL-STD-202, Method 208
- Weight: 0.055 grams (Approximate)
Important Notice
Diodes Incorporated provides information for illustrative purposes only and assumes no liability for its use. Users are responsible for evaluating product suitability and ensuring compliance with regulations. Diodes does not warrant information accuracy and reserves the right to make changes without notice. This document is in English, which is the authoritative version.
