pca9306 datasheet
Table Of Contents
- 1 Features
- 2 Applications
- 3 Description
- Table of Contents
- 4 Revision History
- 5 Pin Configuration and Functions
- 6 Specifications
- 6.1 Absolute Maximum Ratings
- 6.2 ESD Ratings
- 6.3 Recommended Operating Conditions
- 6.4 Thermal Information
- 6.5 Electrical Characteristics
- 6.6 Switching Characteristics AC Performance (Translating Down) (EN = 3.3 V)
- 6.7 Switching Characteristics AC Performance (Translating Down) (EN = 2.5 V)
- 6.8 Switching Characteristics AC Performance (Translating Up) (EN = 3.3 V)
- 6.9 Switching Characteristics AC Performance (Translating Up) (EN = 2.5 V)
- 6.10 Typical Characteristics
- 7 Parameter Measurement Information
- 8 Detailed Description
- 8.1 Overview
- 8.1.1 Definition of threshold voltage
- 8.1.2 Correct Device Set Up
- 8.1.3 Disconnecting a Slave from the Main I2C Bus Using the EN Pin
- 8.1.4 Supporting Remote Board Insertion to Backplane with PCA9306
- 8.1.5 Switch Configuration
- 8.1.6 Master on Side 1 or Side 2 of Device
- 8.1.7 LDO and PCA9306 Concerns
- 8.1.8 Current Limiting Resistance on VREF2
- 8.2 Functional Block Diagram
- 8.3 Feature Description
- 8.4 Device Functional Modes
- 8.1 Overview
- 9 Application and Implementation
- 10 Power Supply Recommendations
- 11 Layout
- 12 Device and Documentation Support
- 13 Mechanical, Packaging, and Orderable Information
PCA9306
Vref2
200 k
VCC1
EN
SCL1
SDA1
SCL2
SDA2
Vref1
VCC2
I2C slave devices
I2C or SMBus Master
(processor)
PCA9306
Vref2
Translation Configuration
where Vcc2 >= Vref1 + 0.7 V
200 k
VCC1
EN
SCL1
VCC2
SDA1
R
VCC2
SCL2
SDA2
Vref1
VCC2
RR
VCC1 VCC1
12
PCA9306
SCPS113M –OCTOBER 2004–REVISED APRIL 2019
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Product Folder Links: PCA9306
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Overview (continued)
Figure 11. Translation Configuration
When PCA9306 is in the switch configuration (V
REF1
= V
REF2
), the propagation delays are different compared to
the translator configuration. Taking a look at the propagation delays, if the pull up resistance and capacitance on
both sides of the bus are equal, then in switch mode the PCA9306 has the same propagation delay from side
one to two and side two to one. The propagation delays become lower when V
CC1
/V
CC2
is larger. For example,
the propagation delay at 1.8 V is longer than at 5 V in the switching configuration. When PCA9306 is in
translation mode, side one propagate lows to side two faster than side two can propagate lows to side 1. This
time difference becomes larger the larger the difference between V
CC2
and V
CC1
becomes.
8.1.6 Master on Side 1 or Side 2 of Device
I2C and SMBus are bidirectional protocol meaning devices on the bus can both transmit and receive data.
PCA9306 was designed to allow for signals to be able to be transmitted from either side, thus allowing for the
master to be able to placed on either side of the device. Figure 12 shows the master on side two as opposed to
the diagram on page 1 of this data sheet.
Figure 12. Master on side 2 of PCA9306