PCA9512A; PCA9512B Level shifting hot swappable I2C-bus and SMBus bus buffer Rev. 5 — 5 January 2011 Product data sheet 1. General description The PCA9512A/B is a hot swappable I2C-bus and SMBus buffer that allows I/O card insertion into a live backplane without corruption of the data and clock buses and includes two dedicated supply voltage pins to provide level shifting between 3.3 V and 5 V systems while maintaining the best noise margin for each voltage level. Either pin may be powered with supply voltages ranging from 2.7 V to 5.5 V with no constraints on which supply voltage is higher. Control circuitry prevents the backplane from being connected to the card until a stop bit or bus idle occurs on the backplane without bus contention on the card. When the connection is made, the PCA9512A/B provides bidirectional buffering, keeping the backplane and card capacitances isolated. The PCA9512A or PCA9512B can be used if the rise of VCC and VCC2 is simultaneous, but only the PCA9512B shall be used if the interval between rise of VCC and VCC2 is not simultaneous. The PCA9512A/B rise time accelerator circuitry allows the use of weaker DC pull-up currents while still meeting rise time requirements. The PCA9512A/B incorporates a digital input pin that enables and disables the rise time accelerators on all four SDAn and SCLn pins. During insertion, the PCA9512A/B SDAn and SCLn pins are precharged to 1 V to minimize the current required to charge the parasitic capacitance of the chip. The incremental offset design of the PCA9510A/11A/12A/12B/13A/14A I/O drivers allow them to be connected to another PCA9510A/11A/12A/12B/13A/14A device in series or in parallel and to the I2C compliant side of static offset bus buffers, but not to the static offset side of those bus buffers. 2. Features and benefits Bidirectional buffer for SDA and SCL lines increases fan-out and prevents SDA and SCL corruption during live board insertion and removal from multipoint backplane systems Compatible with I2C-bus Standard mode, I2C-bus Fast mode, and SMBus standards Built-in ΔV/Δt rise time accelerators on all SDA and SCL lines (0.6 V threshold) with ability to disable ΔV/Δt rise time accelerator through the ACC pin for lightly loaded systems, requires the bus pull-up voltage and respective supply voltage (VCC or VCC2) to be the same 5 V to 3.3 V level translation with optimum noise margin High-impedance SDAn and SCLn pins for VCC or VCC2 = 0 V 1 V precharge on all SDAn and SCLn pins Supports clock stretching and multiple master arbitration and synchronization PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer Operating power supply voltage range: 2.7 V to 5.5 V 0 Hz to 400 kHz clock frequency ESD protection exceeds 2000 V HBM per JESD22-A114, 200 V MM per JESD22-A115, and 1000 V CDM per JESD22-C101 Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA Packages offered: SO8, TSSOP8 (MSOP8) 3. Applications cPCI, VME, AdvancedTCA cards and other multipoint backplane cards that are required to be inserted or removed from an operating system 4. Feature selection Table 1. Feature selection chart Feature PCA9510A PCA9511A PCA9512A/B PCA9513A PCA9514A Idle detect yes High-impedance SDAn, SCLn pins for VCC = 0 V yes yes yes yes yes yes yes yes yes Rise time accelerator circuitry on SDAn and SCLn pins - yes yes yes yes Rise time accelerator circuitry hardware disable pin for lightly loaded systems - yes - - Rise time accelerator threshold 0.8 V versus 0.6 V improves noise margin - - - yes yes Ready open-drain output yes yes - yes yes Two VCC pins to support 5 V to 3.3 V level translation with improved noise margins - - yes - - 1 V precharge on all SDAn and SCLn pins in only yes yes - - - - yes - 92 μA current source on SCLIN and SDAIN for PICMG applications 5. Ordering information Table 2. Ordering information Tamb = −40 °C to +85 °C Type number Topside mark Package Name Description Version PCA9512AD PA9512A SO8 plastic small outline package; 8 leads; body width 3.9 mm SOT96-1 PCA9512BD PA9512B PCA9512ADP 9512A TSSOP8[1] plastic thin shrink small outline package; 8 leads; body width 3 mm SOT505-1 PCA9512BDP 9512B [1] Also known as MSOP8. Standard packing quantities and other packaging data are available at the NXP web site. PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 2 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 6. Block diagram PCA9512A/B VCC2 VCC 2 mA 2 mA SLEW RATE DETECTOR SLEW RATE DETECTOR ACC BACKPLANE-TO-CARD CONNECTION SDAIN CONNECT SDAOUT CONNECT CONNECT 100 kΩ RCH3 100 kΩ RCH1 1 VOLT PRECHARGE 100 kΩ RCH2 100 kΩ RCH4 2 mA 2 mA SLEW RATE DETECTOR SLEW RATE DETECTOR ACC ACC BACKPLANE-TO-CARD CONNECTION SCLIN SCLOUT CONNECT CONNECT STOP BIT AND BUS IDLE 0.5 μA 0.55VCC/ 0.45VCC 0.55VCC/ 0.45VCC UVLO CONNECT 20 pF 100 μs DELAY UVLO CONNECT RD QB S GND 0.5 pF 002aab788 Fig 1. Block diagram of PCA9512A/B PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 3 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 7. Pinning information 7.1 Pinning VCC2 1 SCLOUT 2 SCLIN 3 GND 4 PCA9512AD PCA9512BD 8 VCC 7 SDAOUT 6 SDAIN 5 ACC VCC2 1 8 VCC SCLOUT 2 7 SDAOUT SCLIN 3 GND 4 Pin configuration for SO8 6 SDAIN 5 ACC 002aab790 002aab789 Fig 2. PCA9512ADP PCA9512BDP Fig 3. Pin configuration for TSSOP8 7.2 Pin description Table 3. Pin description Symbol Pin Description VCC2 1 Supply voltage for devices on the card I2C-bus. Connect pull-up resistors from SDAOUT and SCLOUT to this pin. SCLOUT 2 serial clock output to and from the SCL bus on the card SCLIN 3 serial clock input to and from the SCL bus on the backplane GND 4 ground supply; connect this pin to a ground plane for best results. ACC 5 CMOS threshold digital input pin that enables and disables the rise time accelerators on all four SDAn and SCLn pins. ACC enables all accelerators when set to VCC2, and turns them off when set to GND. SDAIN 6 serial data input to and from the SDA bus on the backplane SDAOUT 7 serial data output to and from the SDA bus on the card VCC 8 supply voltage; from the backplane, connect pull-up resistors from SDAIN and SCLIN to this pin. 8. Functional description Refer to Figure 1 “Block diagram of PCA9512A/B”. 8.1 Start-up When the PCA9512A/B is powered up, either VCC or VCC2 may rise first, within a short time of each other and either may be more positive or they may be equal, however the PCA9512A/B will not leave the undervoltage lockout or initialization state until both VCC and VCC2 have gone above 2.5 V. If either VCC or VCC2 drops below 2.0 V it will return to the undervoltage lockout state. Use of PCA9512B is required where the interval between rise of VCC and VCC2 is not simultaneous. In the undervoltage lockout state the connection circuitry is disabled, the rise time accelerators are disabled, and the precharge circuitry is also disabled. After both VCC and VCC2 are valid, independent of which is higher, the PCA9512A/B enters the initialization state; during this state the 1 V precharge circuitry is activated and pulls up the SDAn and SCLn pins to 1 V through individual 100 kΩ nominal resistors. At the end of the initialization state the ‘Stop bit and PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 4 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer bus idle’ detect circuit is enabled. When all the SDAn and SCLn pins have been HIGH for the bus idle time or when all pins are HIGH and a STOP condition is seen on the SDAIN and SCLIN pins, the connect circuitry is activated, connecting SDAIN to SDAOUT and SCLIN to SCLOUT. The 1 V precharge circuitry is disabled when the connection is made, unless the ACC pin is LOW; the rise time accelerators are enabled at this time also. 8.2 Connect circuitry Once the connection circuitry is activated, the behavior of SDAIN and SDAOUT as well as SCLIN and SCLOUT become identical, with each acting as a bidirectional buffer that isolates the input bus capacitance from the output bus capacitance while communicating. If VCC ≠ VCC2, then a level shifting function is performed between input and output. A LOW forced on either SDAIN or SDAOUT will cause the other pin to be driven to a LOW by the PCA9512A/B. The same is also true for the SCLn pins. Noise between 0.7VCC and VCC on the SDAIN and SCLIN pins, and 0.7VCC2 and VCC2 on the SDAOUT and SCLOUT pins is generally ignored because a falling edge is only recognized when it falls below 0.7VCC for SDAIN and SCLIN (or 0.7VCC2 for SDAOUT and SCLOUT pins) with a slew rate of at least 1.25 V/μs. When a falling edge is seen on one pin, the other pin in the pair turns on a pull-down driver that is referenced to a small voltage above the falling pin. The driver will pull the pin down at a slew rate determined by the driver and the load. The first falling pin may have a fast or slow slew rate; if it is faster than the pull-down slew rate, then the initial pull-down rate will continue until it is LOW. If the first falling pin has a slow slew rate, then the second pin will be pulled down at its initial slew rate only until it is just above the first pin voltage then they will both continue down at the slew rate of the first. Once both sides are LOW they will remain LOW until all the external drivers have stopped driving LOWs. If both sides are being driven LOW to the same (or nearly the same) value by external drivers, which is the case for clock stretching and is typically the case for acknowledge, and one side external driver stops driving, that pin will rise and rise above the nominal offset voltage until the internal driver catches up and pulls it back down to the offset voltage. This bounce is worst for low capacitances and low resistances, and may become excessive. When the last external driver stops driving a LOW, that pin will bounce up and settle out just above the other pin as both rise together with a slew rate determined by the internal slew rate control and the RC time constant. As long as the slew rate is at least 1.25 V/μs, when the pin voltage exceeds 0.6 V, the rise time accelerator circuits are turned on and the pull-down driver is turned off. If the ACC pin is LOW, the rise time accelerator circuits will be disabled, but the pull-down driver will still turn off. 8.3 Maximum number of devices in series Each buffer adds about 0.1 V dynamic level offset at 25 °C with the offset larger at higher temperatures. Maximum offset (Voffset) is 0.150 V with a 10 kΩ pull-up resistor. The LOW level at the signal origination end (master) is dependent upon the load and the only specification point is the I2C-bus specification of 3 mA will produce VOL < 0.4 V, although if lightly loaded the VOL may be ~0.1 V. Assuming VOL = 0.1 V and Voffset = 0.1 V, the level after four buffers would be 0.5 V, which is only about 0.1 V below the threshold of the rising edge accelerator (about 0.6 V). With great care a system with four buffers may work, but as the VOL moves up from 0.1 V, noise or bounces on the line will result in firing the rising edge accelerator thus introducing false clock edges. Generally it is recommended to limit the number of buffers in series to two, and to keep the load light to minimize the offset. PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 5 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer The PCA9510A (rise time accelerator is permanently disabled) and the PCA9512A/B (rise time accelerator can be turned off) are a little different with the rise time accelerator turned off because the rise time accelerator will not pull the node up, but the same logic that turns on the accelerator turns the pull-down off. If the VIL is above ~0.6 V and a rising edge is detected, the pull-down will turn off and will not turn back on until a falling edge is detected. buffer A MASTER buffer B SLAVE B common node buffer C SLAVE C 002aab581 Fig 4. System with 3 buffers connected to common node Consider a system with three buffers connected to a common node and communication between the Master and Slave B that are connected at either end of buffer A and buffer B in series as shown in Figure 4. Consider if the VOL at the input of buffer A is 0.3 V and the VOL of Slave B (when acknowledging) is 0.4 V with the direction changing from Master to Slave B and then from Slave B to Master. Before the direction change you would observe VIL at the input of buffer A of 0.3 V and its output, the common node, is ~0.4 V. The output of buffer B and buffer C would be ~0.5 V, but Slave B is driving 0.4 V, so the voltage at Slave B is 0.4 V. The output of buffer C is ~0.5 V. When the Master pull-down turns off, the input of buffer A rises and so does its output, the common node, because it is the only part driving the node. The common node will rise to 0.5 V before buffer B’s output turns on, if the pull-up is strong the node may bounce. If the bounce goes above the threshold for the rising edge accelerator ~0.6 V the accelerators on both buffer A and buffer C will fire contending with the output of buffer B. The node on the input of buffer A will go HIGH as will the input node of buffer C. After the common node voltage is stable for a while the rising edge accelerators will turn off and the common node will return to ~0.5 V because the buffer B is still on. The voltage at both the Master and Slave C nodes would then fall to ~0.6 V until Slave B turned off. This would not cause a failure on the data line as long as the return to 0.5 V on the common node (~0.6 V at the Master and Slave C) occurred before the data setup time. If this were the SCL line, the parts on buffer A and buffer C would see a false clock rather than a stretched clock, which would cause a system error. 8.4 Propagation delays The delay for a rising edge is determined by the combined pull-up current from the bus resistors and the rise time accelerator current source and the effective capacitance on the lines. If the pull-up currents are the same, any difference in rise time is directly proportional to the difference in capacitance between the two sides. The tPLH may be negative if the output capacitance is less than the input capacitance and would be positive if the output capacitance is larger than the input capacitance, when the currents are the same. The tPHL can never be negative because the output does not start to fall until the input is below 0.7VCC (or 0.7VCC2 for SDAOUT and SCLOUT), and the output turn on has a non-zero delay, and the output has a limited maximum slew rate, and even if the input PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 6 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer slew rate is slow enough that the output catches up it will still lag the falling voltage of the input by the offset voltage. The maximum tPHL occurs when the input is driven LOW with zero delay and the output is still limited by its turn-on delay and the falling edge slew rate. The output falling edge slew rate is a function of the internal maximum slew rate which is a function of temperature, VCC or VCC2 and process, as well as the load current and the load capacitance. 8.5 Rise time accelerators During positive bus transactions, a 2 mA current source is switched on to quickly slew the SDA and SCL lines HIGH once the input level of 0.6 V for the PCA9512A/B is exceeded. The rising edge rate should be at least 1.25 V/μs to guarantee turn on of the accelerators. The built-in ΔV/Δt rise time accelerators on all SDA and SCL lines requires the bus pull-up voltage and respective supply voltage (VCC or VCC2) to be the same. The built-in ΔV/Δt rise time accelerators can be disabled through the ACC pin for lightly loaded systems. 8.6 ACC boost current enable Users having lightly loaded systems may wish to disable the rise time accelerators. Driving this pin to ground turns off the rise time accelerators on all four SDAn and SCLn pins. Driving this pin to the VCC2 voltage enables normal operation of the rise time accelerators. 8.7 Resistor pull-up value selection The system pull-up resistors must be strong enough to provide a positive slew rate of 1.25 V/μs on the SDAn and SCLn pins, in order to activate the boost pull-up currents during rising edges. Choose maximum resistor value using the formula given in Equation 1: 3 V CC ( min ) – 0.6 R PU ≤ 800 × 10 ⎛ -----------------------------------⎞ ⎝ ⎠ C (1) where RPU is the pull-up resistor value in Ω, VCC(min) is the minimum VCC voltage in volts, and C is the equivalent bus capacitance in picofarads. In addition, regardless of the bus capacitance, always choose RPU ≤ 65.7 kΩ for VCC = 5.5 V maximum, RPU ≤ 45 kΩ for VCC = 3.6 V maximum. The start-up circuitry requires logic HIGH voltages on SDAOUT and SCLOUT to connect the backplane to the card, and these pull-up values are needed to overcome the precharge voltage. See the curves in Figure 5 and Figure 6 for guidance in resistor pull-up selection. PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 7 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 002aae782 50 RPU (kΩ) Rmax = 45 kΩ 40 (1) 30 rise time = 300 ns(2) 20 rise time = 20 ns 10 Rmin = 1 kΩ 0 0 100 200 300 400 Cb (pF) (1) Unshaded area indicates recommended pull-up, for rise time < 300 ns, with rise time accelerator turned on. (2) Rise time accelerator off. Fig 5. Bus requirements for 3.3 V systems 002aae783 70 RPU (kΩ) Rmax = 65.7 kΩ 60 50 (1) 40 rise time = 300 ns(2) 30 20 rise time = 20 ns 10 Rmin = 1.7 kΩ 0 0 100 200 300 400 Cb (pF) (1) Unshaded area indicates recommended pull-up, for rise time < 300 ns, with rise time accelerator turned on. (2) Rise time accelerator off. Fig 6. Bus requirements for 5 V systems PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 8 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 8.8 Hot swapping and capacitance buffering application Figure 7 through Figure 9 illustrate the usage of the PCA9512A in applications that take advantage of both its hot swapping and capacitance buffering features. In all of these applications, note that if the I/O cards were plugged directly into the backplane, all of the backplane and card capacitances would add directly together, making rise time and fall time requirements difficult to meet. Placing a bus buffer on the edge of each card, however, isolates the card capacitance from the backplane. For a given I/O card, the PCA9512A drives the capacitance of everything on the card and the backplane must drive only the capacitance of the bus buffer, which is less than 10 pF, the connector, trace, and all additional cards on the backplane. See Application Note AN10160, ‘Hot Swap Bus Buffer’ for more information on applications and technical assistance. BACKPLANE CONNECTOR BACKPLANE R1 10 kΩ STAGGERED CONNECTOR VCC SDA SCL STAGGERED CONNECTOR BD_SEL I/O PERIPHERAL CARD 1 POWER SUPPLY HOT SWAP POWER SUPPLY HOT SWAP STAGGERED CONNECTOR VCC2 POWER SUPPLY HOT SWAP R3 5.1 Ω C2 C1 0.01 μF R4 10 kΩ R5 10 kΩ R6 10 kΩ PCA9512A 0.01 μF VCC SDAIN SCLIN VCC2 GND SDAOUT SCLOUT ACC CARD1_SDA CARD1_SCL R2 10 kΩ I/O PERIPHERAL CARD 2 R7 5.1 Ω C4 C3 0.01 μF R8 10 kΩ R9 10 kΩ R10 10 kΩ PCA9512A 0.01 μF VCC SDAIN SCLIN VCC2 GND SDAOUT SCLOUT ACC CARD2_SDA CARD2_SCL I/O PERIPHERAL CARD N R11 5.1 Ω C6 C5 0.01 μF R12 10 kΩ R13 10 kΩ R14 10 kΩ PCA9512A 0.01 μF VCC SDAIN SCLIN VCC2 GND SDAOUT SCLOUT ACC CARDN_SDA CARDN_SCL 002aab791 Remark: Application assumes bus capacitance within ‘proper operation’ region of Figure 5 and Figure 6. Fig 7. Hot swapping multiple I/O cards into a backplane using the PCA9512A in a cPCI, VME, and AdvancedTCA system PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 9 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer BACKPLANE CONNECTOR BACKPLANE STAGGERED CONNECTOR I/O PERIPHERAL CARD 1 VCC2 VCC SDA SCL R1 10 kΩ C1 0.01 μF R4 10 kΩ R5 10 kΩ R6 10 kΩ PCA9512A R3 5.1 Ω C2 0.01 μF VCC2 VCC SDAIN SCLIN GND SDAOUT SCLOUT ACC CARD1_SDA CARD1_SCL R2 10 kΩ STAGGERED CONNECTOR I/O PERIPHERAL CARD 2 C3 0.01 μF R8 10 kΩ R9 10 kΩ R10 10 kΩ PCA9512A R7 5.1 Ω C4 0.01 μF VCC SDAIN SCLIN VCC2 GND SDAOUT SCLOUT ACC CARD2_SDA CARD2_SCL 002aab792 Remark: Application assumes bus capacitance within ‘proper operation’ region of Figure 5 and Figure 6. Fig 8. Hot swapping multiple I/O cards into a backplane using the PCA9512A with a custom connector CARD_VCC (3 V) VCC (5 V) R1 10 kΩ R4 10 kΩ C2 0.01 μF C1 0.01 μF VCC SDA SCL SDAIN SCLIN R3 10 kΩ R2 10 kΩ VCC2 SDAOUT PCA9512A SCLOUT CARD_SDA CARD_SCL ACC GND 002aab793 Remark: Application assumes bus capacitance within ‘proper operation’ region of Figure 5 and Figure 6. Fig 9. 5 V to 3.3 V level translator and bus buffer PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 10 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 9. Application design-in information VCC (5 V) CARD_VCC (3 V) R1 10 kΩ R2 10 kΩ C2 0.01 μF C1 0.01 μF SCL R4 10 kΩ R5 10 kΩ VCC2 VCC SDA R3 10 kΩ SDAIN SDAOUT SCLIN SCLOUT CARD_SDA CARD_SCL PCA9512A/B ACC GND 002aab794 Fig 10. Typical application 10. Limiting values Table 4. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol Parameter Min Max Unit VCC supply voltage Conditions −0.5 +7 V VCC2 supply voltage 2[1] −0.5 +7 V Vn voltage on any other pin −0.5 +7 V - ±20 mA - ±50 mA II input current [2] II/O input/output current [3] Toper operating temperature −40 +85 °C Tstg storage temperature −65 +125 °C Tsp solder point temperature - 300 °C Tj(max) maximum junction temperature - 125 °C [1] 10 s maximum Card side supply voltage. [2] Maximum current for inputs. [3] Maximum current for I/O pins. PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 11 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 11. Characteristics Table 5. Characteristics VCC = 2.7 V to 5.5 V; Tamb = −40 °C to +85 °C; unless otherwise specified. Symbol Parameter Conditions Min Typ Max Unit Power supply VCC supply voltage [1] 2.7 - 5.5 V VCC2 supply voltage 2[2] [1] 2.7 - 5.5 V ICC supply current VCC = 5.5 V; VSDAIN = VSCLIN = 0 V - 1.8 3.6 mA ICC2 supply current 2 VCC = 5.5 V; VSDAOUT = VSCLOUT = 0 V - 1.7 2.9 mA 1.1 1.2 V Start-up circuitry Vpch precharge voltage ten enable time tidle idle time SDA, SCL floating [1] 0.8 on power-up [3] - 180 - μs [1][4] 50 140 250 μs [5][6] 1 2 - mA Rise time accelerators Itrt(pu) transient boosted pull-up current positive transition on SDA, SCL; VACC = 0.7 × VCC2; VCC = 2.7 V; slew rate = 1.25 V/μs Vth(dis)(ACC) disable threshold voltage on pin ACC 0.3VCC2 0.5VCC2 - Vth(en)(ACC) enable threshold voltage on pin ACC - 0.5VCC2 0.7VCC2 V II(ACC) input current on pin ACC −1 ±0.1 +1 μA - 5 - ns 0 115 175 mV - - 10 pF 0 0.3 0.4 V −1 - +1 μA tPD(on/off)(ACC) on/off propagation delay on pin ACC V Input-output connection Voffset offset voltage 10 kΩ to VCC on SDA, SCL; VCC = 3.3 V; VCC2 = 3.3 V; VI = 0.2 V Ci input capacitance digital; guaranteed by design, not subject to test VOL LOW-level output voltage VI = 0 V; SDAn, SCLn pins; Isink = 3 mA; VCC = 2.7 V; VCC2 = 2.7 V ILI input leakage current SDAn, SCLn pins; VCC = 5.5 V; VCC2 = 5.5 V PCA9512A_PCA9512B Product data sheet [1][7] [1] All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 12 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer Table 5. Characteristics …continued VCC = 2.7 V to 5.5 V; Tamb = −40 °C to +85 °C; unless otherwise specified. Symbol Parameter Conditions Min Typ Max Unit System characteristics SCL clock frequency [8] 0 - 400 kHz tBUF bus free time between a STOP and START condition [8] 1.3 - - μs tHD;STA hold time (repeated) START condition [8] 0.6 - - μs tSU;STA set-up time for a repeated START condition [8] 0.6 - - μs tSU;STO set-up time for STOP condition [8] 0.6 - - μs tHD;DAT data hold time [8] 300 - - ns tSU;DAT data set-up time [8] 100 - - ns tLOW LOW period of the SCL clock [8] 1.3 - - μs tHIGH HIGH period of the SCL clock [8] 0.6 - - μs tf fall time of both SDA and SCL signals [8][9] 20 + 0.1 × Cb - 300 ns tr rise time of both SDA and SCL signals [8][9] 20 + 0.1 × Cb - 300 ns fSCL [1] This specification applies over the full operating temperature range. [2] Card side supply voltage. [3] The enable time is from power-up of VCC and VCC2 ≥ 2.7 V to when idle or stop time begins. [4] Idle time is from when SDAn and SCLn are HIGH after enable time has been met. [5] Itrt(pu) varies with temperature and VCC voltage, as shown in Section 11.1 “Typical performance characteristics”. [6] Input pull-up voltage should not exceed power supply voltage in operating mode because the rise time accelerator will clamp the voltage to the positive supply rail. [7] The connection circuitry always regulates its output to a higher voltage than its input. The magnitude of this offset voltage as a function of the pull-up resistor and VCC voltage is shown in Section 11.1 “Typical performance characteristics”. [8] Guaranteed by design, not production tested. [9] Cb = total capacitance of one bus line in pF. PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 13 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 11.1 Typical performance characteristics 002aab795 2.15 ICC (mA) Itrt(pu) (mA) VCC = 5.5 V 3.3 V 2.7 V 1.95 002aab796 12 VCC = 5 V 8 1.75 4 3.3 V 1.55 2.7 V 1.35 −40 +25 +90 Tamb (°C) 0 −40 +25 +90 Tamb (°C) ICC2 (pin 1) typical current averages 0.1 mA less than ICC on pin 8. Fig 11. ICC versus temperature Fig 12. Itrt(pu) versus temperature 002aab589 90 VCC = 5.5 V 002aab591 350 VO − VI (mV) tPHL (ns) 250 80 2.7 V 3.3 V 70 150 VCC = 5 V 3.3 V 60 −40 50 +25 +90 Ci = Co > 100 pF; RPU(in) = RPU(out) = 10 kΩ Fig 13. Input/output tPHL versus temperature PCA9512A_PCA9512B Product data sheet 0 10 20 30 40 RPU (kΩ) Tamb (°C) VCC = 3.3 V or 5.5 V Fig 14. Connection circuitry VO − VI All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 14 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 12. Test information VCC VCC PULSE GENERATOR VI VO RL 10 kΩ DUT RT CL 100 pF 002aab595 RL = load resistor CL = load capacitance includes jig and probe capacitance RT = termination resistance should be equal to the output impedance Zo of the pulse generator Fig 15. Test circuitry for switching times PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 15 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 13. Package outline SO8: plastic small outline package; 8 leads; body width 3.9 mm SOT96-1 D E A X c y HE v M A Z 5 8 Q A2 A (A 3) A1 pin 1 index θ Lp L 4 1 e detail X w M bp 0 2.5 5 mm scale DIMENSIONS (inch dimensions are derived from the original mm dimensions) UNIT A max. A1 A2 A3 bp c D (1) E (2) e HE L Lp Q v w y Z (1) mm 1.75 0.25 0.10 1.45 1.25 0.25 0.49 0.36 0.25 0.19 5.0 4.8 4.0 3.8 1.27 6.2 5.8 1.05 1.0 0.4 0.7 0.6 0.25 0.25 0.1 0.7 0.3 inches 0.069 0.010 0.057 0.004 0.049 0.01 0.019 0.0100 0.014 0.0075 0.20 0.19 0.16 0.15 0.05 0.01 0.01 0.004 0.028 0.012 0.244 0.039 0.028 0.041 0.228 0.016 0.024 θ 8o o 0 Notes 1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included. 2. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included. REFERENCES OUTLINE VERSION IEC JEDEC SOT96-1 076E03 MS-012 JEITA EUROPEAN PROJECTION ISSUE DATE 99-12-27 03-02-18 Fig 16. Package outline SOT96-1 (SO8) PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 16 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer TSSOP8: plastic thin shrink small outline package; 8 leads; body width 3 mm D E SOT505-1 A X c y HE v M A Z 5 8 A2 pin 1 index (A3) A1 A θ Lp L 1 4 detail X e w M bp 0 2.5 5 mm scale DIMENSIONS (mm are the original dimensions) UNIT A max. A1 A2 A3 bp c D(1) E(2) e HE L Lp v w y Z(1) θ mm 1.1 0.15 0.05 0.95 0.80 0.25 0.45 0.25 0.28 0.15 3.1 2.9 3.1 2.9 0.65 5.1 4.7 0.94 0.7 0.4 0.1 0.1 0.1 0.70 0.35 6° 0° Notes 1. Plastic or metal protrusions of 0.15 mm maximum per side are not included. 2. Plastic or metal protrusions of 0.25 mm maximum per side are not included. OUTLINE VERSION REFERENCES IEC JEDEC JEITA EUROPEAN PROJECTION ISSUE DATE 99-04-09 03-02-18 SOT505-1 Fig 17. Package outline SOT505-1 (TSSOP8) PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 17 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 14. Soldering of SMD packages This text provides a very brief insight into a complex technology. A more in-depth account of soldering ICs can be found in Application Note AN10365 “Surface mount reflow soldering description”. 14.1 Introduction to soldering Soldering is one of the most common methods through which packages are attached to Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both the mechanical and the electrical connection. There is no single soldering method that is ideal for all IC packages. Wave soldering is often preferred when through-hole and Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high densities that come with increased miniaturization. 14.2 Wave and reflow soldering Wave soldering is a joining technology in which the joints are made by solder coming from a standing wave of liquid solder. The wave soldering process is suitable for the following: • Through-hole components • Leaded or leadless SMDs, which are glued to the surface of the printed circuit board Not all SMDs can be wave soldered. Packages with solder balls, and some leadless packages which have solder lands underneath the body, cannot be wave soldered. Also, leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered, due to an increased probability of bridging. The reflow soldering process involves applying solder paste to a board, followed by component placement and exposure to a temperature profile. Leaded packages, packages with solder balls, and leadless packages are all reflow solderable. Key characteristics in both wave and reflow soldering are: • • • • • • Board specifications, including the board finish, solder masks and vias Package footprints, including solder thieves and orientation The moisture sensitivity level of the packages Package placement Inspection and repair Lead-free soldering versus SnPb soldering 14.3 Wave soldering Key characteristics in wave soldering are: • Process issues, such as application of adhesive and flux, clinching of leads, board transport, the solder wave parameters, and the time during which components are exposed to the wave • Solder bath specifications, including temperature and impurities PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 18 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 14.4 Reflow soldering Key characteristics in reflow soldering are: • Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to higher minimum peak temperatures (see Figure 18) than a SnPb process, thus reducing the process window • Solder paste printing issues including smearing, release, and adjusting the process window for a mix of large and small components on one board • Reflow temperature profile; this profile includes preheat, reflow (in which the board is heated to the peak temperature) and cooling down. It is imperative that the peak temperature is high enough for the solder to make reliable solder joints (a solder paste characteristic). In addition, the peak temperature must be low enough that the packages and/or boards are not damaged. The peak temperature of the package depends on package thickness and volume and is classified in accordance with Table 6 and 7 Table 6. SnPb eutectic process (from J-STD-020C) Package thickness (mm) Package reflow temperature (°C) Volume (mm3) < 350 ≥ 350 < 2.5 235 220 ≥ 2.5 220 220 Table 7. Lead-free process (from J-STD-020C) Package thickness (mm) Package reflow temperature (°C) Volume (mm3) < 350 350 to 2000 > 2000 < 1.6 260 260 260 1.6 to 2.5 260 250 245 > 2.5 250 245 245 Moisture sensitivity precautions, as indicated on the packing, must be respected at all times. Studies have shown that small packages reach higher temperatures during reflow soldering, see Figure 18. PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 19 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer maximum peak temperature = MSL limit, damage level temperature minimum peak temperature = minimum soldering temperature peak temperature time 001aac844 MSL: Moisture Sensitivity Level Fig 18. Temperature profiles for large and small components For further information on temperature profiles, refer to Application Note AN10365 “Surface mount reflow soldering description”. 15. Abbreviations Table 8. PCA9512A_PCA9512B Product data sheet Abbreviations Acronym Description AdvancedTCA Advanced Telecommunications Computing Architecture CDM Charged-Device Model cPCI compact Peripheral Component Interface ESD Electrostatic Discharge HBM Human Body Model I2C-bus Inter-Integrated Circuit bus MM Machine Model PCI Peripheral Component Interface PICMG PCI Industrial Computer Manufacturers Group SMBus System Management Bus VME VERSAModule Eurocard All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 20 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 16. Revision history Table 9. Revision history Document ID Release date Data sheet status Change notice Supersedes PCA9512A_PCA9512B v.5 20110105 Product data sheet - PCA9512A v.4 Modifications: • • Added basic type number PCA9512B Section 1 “General description”: – added (new) second paragraph – fifth paragraph re-written • Section 8.1 “Start-up” modified: – first sentence: inserted phrase “within a short time of each other” – added (new) third sentence PCA9512A v.4 20090819 Product data sheet - PCA9512A v.3 PCA9512A v.3 20090720 Product data sheet - PCA9512A v.2 PCA9512A v.2 20090528 Product data sheet - PCA9512A v.1 PCA9512A v.1 20051007 Product data sheet - - PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 21 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 17. Legal information 17.1 Data sheet status Document status[1][2] Product status[3] Definition Objective [short] data sheet Development This document contains data from the objective specification for product development. Preliminary [short] data sheet Qualification This document contains data from the preliminary specification. Product [short] data sheet Production This document contains the product specification. [1] Please consult the most recently issued document before initiating or completing a design. [2] The term ‘short data sheet’ is explained in section “Definitions”. [3] The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status information is available on the Internet at URL http://www.nxp.com. 17.2 Definitions Draft — The document is a draft version only. The content is still under internal review and subject to formal approval, which may result in modifications or additions. NXP Semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences of use of such information. Short data sheet — A short data sheet is an extract from a full data sheet with the same product type number(s) and title. A short data sheet is intended for quick reference only and should not be relied upon to contain detailed and full information. For detailed and full information see the relevant full data sheet, which is available on request via the local NXP Semiconductors sales office. In case of any inconsistency or conflict with the short data sheet, the full data sheet shall prevail. Product specification — The information and data provided in a Product data sheet shall define the specification of the product as agreed between NXP Semiconductors and its customer, unless NXP Semiconductors and customer have explicitly agreed otherwise in writing. In no event however, shall an agreement be valid in which the NXP Semiconductors product is deemed to offer functions and qualities beyond those described in the Product data sheet. 17.3 Disclaimers Limited warranty and liability — Information in this document is believed to be accurate and reliable. However, NXP Semiconductors does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. In no event shall NXP Semiconductors be liable for any indirect, incidental, punitive, special or consequential damages (including - without limitation - lost profits, lost savings, business interruption, costs related to the removal or replacement of any products or rework charges) whether or not such damages are based on tort (including negligence), warranty, breach of contract or any other legal theory. Notwithstanding any damages that customer might incur for any reason whatsoever, NXP Semiconductors’ aggregate and cumulative liability towards customer for the products described herein shall be limited in accordance with the Terms and conditions of commercial sale of NXP Semiconductors. malfunction of an NXP Semiconductors product can reasonably be expected to result in personal injury, death or severe property or environmental damage. NXP Semiconductors accepts no liability for inclusion and/or use of NXP Semiconductors products in such equipment or applications and therefore such inclusion and/or use is at the customer’s own risk. Applications — Applications that are described herein for any of these products are for illustrative purposes only. NXP Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Customers are responsible for the design and operation of their applications and products using NXP Semiconductors products, and NXP Semiconductors accepts no liability for any assistance with applications or customer product design. It is customer’s sole responsibility to determine whether the NXP Semiconductors product is suitable and fit for the customer’s applications and products planned, as well as for the planned application and use of customer’s third party customer(s). Customers should provide appropriate design and operating safeguards to minimize the risks associated with their applications and products. NXP Semiconductors does not accept any liability related to any default, damage, costs or problem which is based on any weakness or default in the customer’s applications or products, or the application or use by customer’s third party customer(s). Customer is responsible for doing all necessary testing for the customer’s applications and products using NXP Semiconductors products in order to avoid a default of the applications and the products or of the application or use by customer’s third party customer(s). NXP does not accept any liability in this respect. Limiting values — Stress above one or more limiting values (as defined in the Absolute Maximum Ratings System of IEC 60134) will cause permanent damage to the device. Limiting values are stress ratings only and (proper) operation of the device at these or any other conditions above those given in the Recommended operating conditions section (if present) or the Characteristics sections of this document is not warranted. Constant or repeated exposure to limiting values will permanently and irreversibly affect the quality and reliability of the device. Terms and conditions of commercial sale — NXP Semiconductors products are sold subject to the general terms and conditions of commercial sale, as published at http://www.nxp.com/profile/terms, unless otherwise agreed in a valid written individual agreement. In case an individual agreement is concluded only the terms and conditions of the respective agreement shall apply. NXP Semiconductors hereby expressly objects to applying the customer’s general terms and conditions with regard to the purchase of NXP Semiconductors products by customer. Right to make changes — NXP Semiconductors reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice. This document supersedes and replaces all information supplied prior to the publication hereof. No offer to sell or license — Nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication of any license under any copyrights, patents or other industrial or intellectual property rights. Suitability for use — NXP Semiconductors products are not designed, authorized or warranted to be suitable for use in life support, life-critical or safety-critical systems or equipment, nor in applications where failure or Export control — This document as well as the item(s) described herein may be subject to export control regulations. Export might require a prior authorization from national authorities. PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 22 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer Non-automotive qualified products — Unless this data sheet expressly states that this specific NXP Semiconductors product is automotive qualified, the product is not suitable for automotive use. It is neither qualified nor tested in accordance with automotive testing or application requirements. NXP Semiconductors accepts no liability for inclusion and/or use of non-automotive qualified products in automotive equipment or applications. In the event that customer uses the product for design-in and use in automotive applications to automotive specifications and standards, customer (a) shall use the product without NXP Semiconductors’ warranty of the product for such automotive applications, use and specifications, and (b) whenever customer uses the product for automotive applications beyond NXP Semiconductors’ specifications such use shall be solely at customer’s own risk, and (c) customer fully indemnifies NXP Semiconductors for any liability, damages or failed product claims resulting from customer design and use of the product for automotive applications beyond NXP Semiconductors’ standard warranty and NXP Semiconductors’ product specifications. 17.4 Trademarks Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. I2C-bus — logo is a trademark of NXP B.V. 18. Contact information For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: [email protected] PCA9512A_PCA9512B Product data sheet All information provided in this document is subject to legal disclaimers. Rev. 5 — 5 January 2011 © NXP B.V. 2011. All rights reserved. 23 of 24 PCA9512A; PCA9512B NXP Semiconductors Level shifting hot swappable I2C-bus and SMBus bus buffer 19. Contents 1 2 3 4 5 6 7 7.1 7.2 8 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 9 10 11 11.1 12 13 14 14.1 14.2 14.3 14.4 15 16 17 17.1 17.2 17.3 17.4 18 19 General description . . . . . . . . . . . . . . . . . . . . . . 1 Features and benefits . . . . . . . . . . . . . . . . . . . . 1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Feature selection . . . . . . . . . . . . . . . . . . . . . . . . 2 Ordering information . . . . . . . . . . . . . . . . . . . . . 2 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Pinning information . . . . . . . . . . . . . . . . . . . . . . 4 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4 Functional description . . . . . . . . . . . . . . . . . . . 4 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Connect circuitry . . . . . . . . . . . . . . . . . . . . . . . . 5 Maximum number of devices in series . . . . . . . 5 Propagation delays . . . . . . . . . . . . . . . . . . . . . . 6 Rise time accelerators . . . . . . . . . . . . . . . . . . . 7 ACC boost current enable . . . . . . . . . . . . . . . . 7 Resistor pull-up value selection . . . . . . . . . . . . 7 Hot swapping and capacitance buffering application . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Application design-in information . . . . . . . . . 11 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 11 Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 12 Typical performance characteristics . . . . . . . . 14 Test information . . . . . . . . . . . . . . . . . . . . . . . . 15 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 16 Soldering of SMD packages . . . . . . . . . . . . . . 18 Introduction to soldering . . . . . . . . . . . . . . . . . 18 Wave and reflow soldering . . . . . . . . . . . . . . . 18 Wave soldering . . . . . . . . . . . . . . . . . . . . . . . . 18 Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . 19 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Revision history . . . . . . . . . . . . . . . . . . . . . . . . 21 Legal information. . . . . . . . . . . . . . . . . . . . . . . 22 Data sheet status . . . . . . . . . . . . . . . . . . . . . . 22 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Contact information. . . . . . . . . . . . . . . . . . . . . 23 Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Please be aware that important notices concerning this document and the product(s) described herein, have been included in section ‘Legal information’. © NXP B.V. 2011. All rights reserved. For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: [email protected] Date of release: 5 January 2011 Document identifier: PCA9512A_PCA9512B