PCA9509GM Level translating I²C-bus/SMBus repeater

The PCA9509 is a level translating I²C-bus/SMBus repeater that enables processor low voltage 2-wire serial bus to interface with standard I²C-bus or SMBus I/O. While retaining all the operating modes and features of the I²C-bus system during the level shifts, it also permits extension of the I²C-bus by providing bidirectional buffering for both the data (SDA) and the clock (SCL) lines, thus enabling the I²C-bus or SMBus maximum capacitance of 400 pF on the higher voltage side. Port A allows a voltage range from 1.0 V (as low as 0.95 V in special cases) to VCC(B) - 1.0 V and requires no external pull-up resistors due to the internal current source. Port B allows a voltage range from 3.0 V to 5.5 V and is overvoltage tolerant. Both port A and port B SDA and SCL pins are high-impedance when the PCA9509 is unpowered.

The bus port B drivers are compliant with SMBus I/O levels, while port A uses a current sensing mechanism to detect the input or output LOW signal which prevents bus lock-up. Port A uses a 1 mA current source for pull-up and a 200 Ω pull-down driver. This results in a LOW on the port A accommodating smaller voltage swings. The output pull-down on the port A internal buffer LOW is set for approximately 0.2 V, while the input threshold of the internal buffer is set about 50 mV lower than that of the output voltage LOW. When the port A I/O is driven LOW internally, the LOW is not recognized as a LOW by the input. This prevents a lock-up condition from occurring. The output pull-down on the port B drives a hard LOW and the input level is set at 0.3 of SMBus or I²C-bus voltage level which enables port B to connect to any other I²C-bus devices or buffer.

The PCA9509 drivers are not enabled unless VCC(A) is above 0.8 V and VCC(B) is above 2.5 V. The enable (EN) pin can also be used to turn the drivers on and off under system control. Caution should be observed to only change the state of the EN pin when the bus is idle

产品特点 Features

Bidirectional buffer isolates capacitance and allows 400 pF on port B of the device
Voltage level translation from port A (1 V [0.95 V in special cases] to VCC(B) - 1.0 V) to port B (3.0 V to 5.5 V)
Requires no external pull-up resistors on lower voltage port A
Active HIGH repeater enable input
Open-drain inputs/outputs
Lock-up free operation
Supports arbitration and clock stretching across the repeater
Accommodates Standard-mode and Fast-mode I²C-bus devices and multiple masters
Powered-off high-impedance I²C-bus pins
Operating supply voltage range of 1.0 V (0.95 V in special cases) to VCC(B) - 1.0 V on port A, 3.0 V to 5.5 V on port B
5 V tolerant port B SCL, SDA and enable pins
0 Hz to 400 kHz clock frequency

Remark: The maximum system operating frequency may be less than 400 kHz because of the delays added by the repeater.
ESD protection exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101
Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA
Packages offered: TSSOP8, SO8, XQFN8

应用

服务器
RAID系统
工业控制
医疗设备
PLC
手机
赌博机
仪器和测试测量

功能框图

封装

型号	可订购的器件编号	订购码 (12NC)	产品状态	封装
PCA9509GM	9352 841 39125	PCA9509GM,125	量产	XQFN8 (SOT902-2)

订货和供应

型号	订购码 (12NC)	可订购的器件编号	化学成分
PCA9509GM	9352 841 39125	PCA9509GM,125	PCA9509GM

PCA9509GM 技术支持

档案名称	标题	类型	格式
PCA9509GM	Level translating I2C-bus/SMBus repeater	Data sheet	pdf
AN10441	Level shifting techniques in I2C-bus design	Application note	pdf
AN255	I2C / SMBus Repeaters, Hubs and Expanders	Application note	pdf
AN10710	Features and applications of the PCA9509 I2C-bus extender	Application note	pdf
75016527	Extend standard I2C-bus devices without worrying about offset voltages; NXP I2C-bus extender PCA9509 in a proven application	Brochure	pdf
75016532	Extend the I2C-bus with advanced repeaters and hubs; NXP 2-channel I2C-bus repeaters PCA9515x and 5-channel I2C-bus hubs PCA9516x	Leaflet	pdf
75016080	Extend the reach of any I2C-bus system without special offset voltage levels; NXP I2C-bus extender PCA9509	Leaflet	pdf
75017424	NXP I2C-bus solutions 2013: Smart, simple solutions for the 12 most common design concerns	Leaflet	pdf
UM10204	I2C-bus specification and user manual	User manual	pdf
UM10206	I2C Demonstration Board 2005-1 Quick Start Guide	User manual	pdf
UM10323	PCA9600 demonstration board OM6293	User manual	pdf