LTC4151IMS#TRPBF

LTC4151 High Voltage I2C Current and Voltage Monitor Features Description Wide Operating Voltage Range: 7V to 80V 12-Bit Resolution for Both Current and Voltages I2C Interface Additional ADC Input Monitors an External Voltage Continuous Scan and Snapshot Modes Shutdown Mode (LTC4151) Reduces Quiescent Current to 120µA n Split SDA for Opto-Isolation (LTC4151-1/LTC4151-2) n Available in 10-Lead MSOP, 10-Lead 3mm × 3mm DFN and 16-Lead SO Packages The LTC®4151 is a high side power monitor that operates over a wide voltage range of 7V to 80V. In default operation mode, the onboard 12-bit ADC continuously measures high side current, input voltage and an external voltage. Data is reported through the I2C interface when polled by a host. The LTC4151 can also perform on-demand measurement in a snapshot mode. The LTC4151 features a dedicated shutdown pin to reduce power consumption. The LTC4151‑1/LTC4151-2 feature split I2C data pins to drive opto-isolators. The data out on the LTC4151-1 is inverted while that on the LTC4151-2 is not. n n n n n n Applications –48V Telecom Infrastructure n Automotive n Industrial n Consumer n PART PACKAGE FEATURED PIN LTC4151 DD10, MS10 SHDN LTC4151-1 DD10, MS10 SDAO LTC4151-2 S16 SDAO L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical Application 12-Bit ADC DNL and INL 1.0 High Side Power Sensing with Onboard ADC and I2C 3.3V 0.02Ω VIN 7V TO 80V VIN 2k ADR1 VDD 2k –1.0 µCONTROLLER SHDN LTC4151 SCL SCL SDA SDA 1024 2048 3072 4096 4151 TA01b 1.0 4151 TA01 0.5 ADC INL (LSB) ADIN GND MEASURED VOLTAGE 0 CODE GND ADR0 0 –0.5 VOUT SENSE+ SENSE– ADC DNL (LSB) 0.5 0 –0.5 –1.0 0 1024 2048 CODE 3072 4096 4151 TA01c 4151ff For more information www.linear.com/LTC4151 1 LTC4151 Absolute Maximum Ratings (Notes 1, 3) VIN Voltage.................................................. –0.3V to 90V SENSE+, SENSE – Voltages............................VIN – 10V or –0.3V to VIN + 0.3V ADR1, ADR0 Voltages ............................... –0.3V to 90V ADIN, SHDN, SDAO, SDAO Voltages............ –0.3V to 6V SCL, SDA, SDAI Voltages (Note 2)............ –0.3V to 5.5V SCL, SDA, SDAI Clamp Current................................ 5mA Operating Temperature Range LTC4151C/LTC4151C-1/LTC4151C-2.......... 0°C to 70°C LTC4151I/LTC4151I-1/LTC4151I-2..........–40°C to 85°C LTC4151H............................................ –40°C to 125°C Storage Temperature Range MSOP, SO........................................... –65°C to 150°C DFN..................................................... –65°C to 125°C Lead Temperature (Soldering, 10 sec) MSOP, SO.......................................................... 300°C Pin Configuration LTC4151 LTC4151 TOP VIEW SENSE+ 1 10 SENSE– VIN 2 9 GND ADR1 3 ADR0 4 7 SDA ADIN 5 6 SCL 11 TOP VIEW SENSE+ VIN ADR1 ADR0 ADIN 8 SHDN 10 9 8 7 6 1 2 3 4 5 SENSE– GND SHDN SDA SCL MS PACKAGE 10-LEAD PLASTIC MSOP TJMAX = 150°C, θJA = 85°C/W DD PACKAGE 10-LEAD (3mm × 3mm) PLASTIC DFN TJMAX = 150°C, θJA = 45°C/W EXPOSED PAD (PIN 11) PCB GND CONNECTION OPTIONAL LTC4151-1 LTC4151-1 TOP VIEW SENSE+ TOP VIEW 10 SENSE– 1 SENSE+ VIN ADR1 ADR0 ADIN 9 GND VIN 2 ADR1 3 ADR0 4 7 SDAI ADIN 5 6 SCL 11 8 SDAO 1 2 3 4 5 10 9 8 7 6 SENSE– GND SDAO SDAI SCL MS PACKAGE 10-LEAD PLASTIC MSOP DD PACKAGE 10-LEAD (3mm × 3mm) PLASTIC DFN TJMAX = 125°C, θJA = 85°C/W TJMAX = 125°C, θJA = 45°C/W EXPOSED PAD (PIN 11) PCB GND CONNECTION OPTIONAL LTC4151-2 TOP VIEW SENSE+ 1 16 SENSE– VIN 2 15 NC NC 3 14 NC NC 4 13 GND ADR1 5 NC 6 ADR0 7 NC 8 12 SDAO 11 SDAI 10 SCL 9 ADIN S PACKAGE 16-LEAD PLASTIC SO TJMAX = 150°C, θJA = 100°C/W 4151ff 2 For more information www.linear.com/LTC4151 LTC4151 Order Information LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC4151CDD#PBF LTC4151CDD#TRPBF LCWZ 10-Lead (3mm × 3mm) Plastic DFN 0°C to 70°C LTC4151IDD#PBF LTC4151IDD#TRPBF LCWZ 10-Lead (3mm × 3mm) Plastic DFN –40°C to 85°C LTC4151HDD#PBF LTC4151HDD#TRPBF LCWZ 10-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LTC4151CDD-1#PBF LTC4151CDD-1#TRPBF LCXC 10-Lead (3mm × 3mm) Plastic DFN 0°C to 70°C LTC4151IDD-1#PBF LTC4151IDD-1#TRPBF LCXC 10-Lead (3mm × 3mm) Plastic DFN –40°C to 85°C LTC4151CMS#PBF LTC4151CMS#TRPBF LTCWY 10-Lead Plastic MSOP 0°C to 70°C LTC4151IMS#PBF LTC4151IMS#TRPBF LTCWY 10-Lead Plastic MSOP –40°C to 85°C LTC4151HMS#PBF LTC4151HMS#TRPBF LTCWY 10-Lead Plastic MSOP –40°C to 125°C LTC4151CMS-1#PBF LTC4151CMS-1#TRPBF LTCXB 10-Lead Plastic MSOP 0°C to 70°C LTC4151IMS-1#PBF LTC4151IMS-1#TRPBF LTCXB 10-Lead Plastic MSOP –40°C to 85°C LTC4151CS-2#PBF LTC4151CS-2#TRPBF LTC4151S-2 16-Lead Plastic SO 0°C to 70°C LTC4151IS-2#PBF LTC4151IS-2#TRPBF LTC4151S-2 16-Lead Plastic SO –40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ Electrical Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN is from 7V to 80V, unless noted. (Note 3) SYMBOL General VIN IIN PARAMETER ISENSE + ISENSE – VSHDN(TH) ISHDN ADC RES VFS SENSE+ Input Current SENSE – Input Current SHDN Input Threshold SHDN Input Current LSB LSB Step Size TUE Total Unadjusted Error VOS Offset Error Supply Voltage Supply Current Resolution (No Missing Codes) Full-Scale Voltage CONDITIONS MIN l VIN = 48V, Normal Operation Mode VIN = 12V, Shutdown Mode VIN, SENSE+, SENSE – = 48V VIN, SENSE+, SENSE – = 48V MAX UNITS 1.2 120 5 0.1 1.5 –5 80 1.7 300 9 1 2 –8 V mA µA µA µA V µA ±1.25 ±1 ±0.75 ±1 ±5 ±6 ±8 Bits mV V V µV mV mV % % % % LSB LSB LSB 7 l l l l SHDN = 0V l 1 –3 (Note 4) (SENSE+ – SENSE – ) VIN ADIN (SENSE+ – SENSE – ) VIN ADIN (SENSE+ – SENSE – ) VIN (Note 5) ADIN, C-Grade ADIN, I-, H-Grade (SENSE+ – SENSE – ) VIN (Note 6) ADIN l 12 l TYP 81.92 102.4 2.048 20 25 0.5 l l l l l l l 4151ff For more information www.linear.com/LTC4151 3 LTC4151 Electrical Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN is from 7V to 80V, unless noted. (Note 3) SYMBOL INL PARAMETER Integral Nonlinearity sT Transition Noise fCONV tCONV Conversion Rate (Continuous Mode) Conversion Time (Snapshot Mode) RADIN ADIN Pin Input Resistance (SENSE+ – SENSE – ) ADIN, VIN ADIN = 3V IADIN I2C Interface VADR(H) VADR(L) IADR(IN) ADIN Pin Input Current ADIN = 3V ADR0, ADR1 Input High Threshold ADRO, ADRI Input Low Threshold ADRO, ADRI Input Current CONDITIONS (SENSE+ – SENSE – ) VIN (Note 5) ADIN (SENSE+ – SENSE – ) VIN ADIN l l l l l 2.3 0.2 l l ±8 l ADR0, ADR1 = 0V or 3V ADR0, ADR1 = 0.8V or 2.2V ISDA, ISDAO, ISDAO = 8mA SDA, SDAI, SDAO, SDAO, SCL = 5V Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: Internal clamps limit the SCL, SDA (LTC4151) and SDAI (LTC4151-1/LTC4151-2) pins to a minimum of 5.5V. Driving these pins to voltages beyond the clamp may damage the part. The pins can be safely tied to higher voltages through a resistor that limits the current below 5mA. 6 53 26 2 TYP ±1 ±1 ±0.5 1.2 0.3 22 7.5 67 33 10 l SDA, SDAO, SDAO Output Low Voltage SDA, SDAI, SDAO, SDAO, SCL Input Current SDA, SDAI, SCL Input Threshold VSDA,SCL(TH) SDA, SDAI, SCL Clamp Voltage ISDA , ISDAI, ISCL = 3mA VSDA,SCL(CL) 2 I C Interface Timing (Note 4) Maximum SCL Clock Frequency fSCL(MAX) Minimum SCL Low Period tLOW Minimum SCL High Period tHIGH Minimum Bus Free Time Between Stop/ tBUF(MIN) Start Condition Minimum Hold Time After (Repeated) Start tHD,STA(MIN) Condition Minimum Repeated Start Condition Set-Up tSU,STA(MIN) Time Minimum Stop Condition Set-Up Time tSU,STO(MIN) Minimum Data Hold Time Input tHD,DATI(MIN) tHD,DATO(MIN) Minimum Data Hold Time Output Minimum Data Set-Up Time Input tSU,DAT(MIN) Maximum Suppressed Spike tSP(MAX) Pulse Width Stuck-Bus Reset Time SCL or SDA/SDAI Held Low tRST SCL, SDA Input Capacitance CX VSDA(OL) ISDA,SCL(IN) MIN l l l l l l l 1.6 5.5 MAX ±3 ±3 ±2 9 85 42 UNITS LSB LSB LSB µVRMS mVRMS µVRMS Hz ms ms ±2 MW µA 2.65 0.6 3.0 0.9 ±70 0.15 0 0.4 ±2 V V µA µA V µA 1.8 6.1 2 6.6 V V 0.65 50 0.12 1.3 600 1.3 kHz µs ns µs 140 600 ns 30 600 ns 30 –100 600 30 110 600 0 900 100 250 ns ns ns ns ns 10 ms pF 400 300 50 20 33 5 Note 3: All currents into pins are positive. All voltages are referenced to GND, unless otherwise noted. Note 4: Guaranteed by design and not subject to test. Note 5: Integral nonlinearity and total unadjusted error of VIN are tested between 7V and 80V. Note 6: Offset error of VIN is defined by extrapolating the straight line measured between 7V and 80V. 4151ff 4 For more information www.linear.com/LTC4151 LTC4151 Typical Performance Characteristics Supply Current vs Supply Voltage (Normal Mode) Supply Current vs Supply Voltage (Shutdown Mode) 400 1.15 – 40°C SUPPLY CURRENT (µA) SUPPLY CURRENT (mA) 1.30 25°C 1.00 85°C 0.85 0.70 VIN = 12V, TA = 25°C, unless noted. 40 60 20 SUPPLY VOLTAGE (V) 0 300 25°C 200 85°C 100 0 80 – 40°C 40 60 20 SUPPLY VOLTAGE (V) 0 4151 G01 4151 G02 ADC DNL vs Code (ADIN Voltage) 1.0 0.05 0.5 0.5 –0.05 –0.10 ADC INL (LSB) 1.0 0 0 0 1024 2048 3072 4096 –1.0 0 –0.5 –0.5 0 1024 CODE 2048 3072 4096 –1.0 ADC DNL vs Code (SENSE Voltage) 1 ADC INL (LSB) 1 ADC DNL (LSB) 0.5 0 –1 1024 2048 3072 4096 CODE –2 0 –1 0 1024 2048 3072 4096 CODE 4151 G06 4096 ADC INL vs Code (SENSE Voltage) 2 –0.5 3072 4151 G05 2 0 2048 CODE 1.0 0 1024 4151 G04 ADC Total Unadjusted Error vs Code (SENSE Voltage) –1.0 0 CODE 4151 G03 ADC TOTAL UNADJUSTED ERROR (%) ADC INL vs Code (ADIN Voltage) 0.10 ADC DNL (LSB) ADC TOTAL UNADJUSTED ERROR (%) ADC Total Unadjusted Error vs Code (ADIN Voltage) 80 –2 0 1024 2048 3072 4096 CODE 4151 G07 4151 G08 4151ff For more information www.linear.com/LTC4151 5 LTC4151 Typical Performance Characteristics 0.5 SDA, SDAO, SDAO Output Low vs Pull-Up Current (VSDA(OL) vs ISDA ) 6.3 VIN = 12V, TA = 25°C, unless noted. SDA, SDAI, SCL Clamp Voltage vs Load Current 85°C 0.4 6.2 0.3 – 40°C 0.2 6.1 – 40°C 6.0 0.1 0 VSDA,SCL(CL) (V) VSDA(OL) (V) 25°C 25°C 0 5 10 15 20 85°C 5.9 0.01 ISDA (mA) 0.1 1 10 ILOAD (mA) 4151 G09 4151 G10 Pin Functions ADIN: ADC Input. The onboard ADC measures voltage range between 0V and 2.048V. Tie to GND if unused. ADR1, ADR0: I2C Device Address Inputs. Connecting ADR1 and ADR0 to VIN, GND or leaving the pins open configures one of nine possible addresses. See Table 1 in the Applications Information section for details. Exposed Pad (DD Package Only): Exposed pad may be left open or connected to device ground (GND). GND: Device Ground. SCL: I2C Bus Clock Input. Data is shifted in and out at the SDA pin on rising edges of SCL. This pin is driven by an open-collector output from a master controller. An external pull-up resistor or current source is required and can be placed between SCL and VIN. The voltage at SCL is internally clamped to 6V (5.5V minimum). SDA (LTC4151 Only): I2C Bus Data Input/Output. Used for shifting in address, command or data bits and sending out data. An external pull-up resistor or current source is required and can be placed between SDA and VIN. The voltage at SDA is internally clamped to 6V (5.5V minimum). SDAI (LTC4151-1/LTC4151-2 Only): I2C Bus Data Input. Used for shifting in address, command, data, and SDAO acknowledge bits. This pin is driven by an open-collector 6 output from a master controller. An external pull-up resistor or current source is required and can be placed between SDAI and VIN. If the master separates SDAI and SDAO, data read at SDAO needs to be echoed back to SDAI for proper I2C communication. The voltage at SDAI is internally clamped to 6V (5.5V minimum). SDAO (LTC4151-2 Only): Serial Bus Data Output. Opendrain output used for sending data back to the master controller or acknowledging a write operation. Normally tied to SDAI to form the SDA line. An external pull-up resistor or current source is required. SDAO (LTC4151-1 Only): Inverted Serial Bus Data Output. Open-drain output used for sending data back to the master controller or acknowledging a write operation. Data is inverted for convenience of opto-isolation. An external pull-up resistor or current source is required. SENSE+: Kelvin Sense of the VIN Pin. See Figure 10 for recommended Kelvin connection. SENSE–: High Side Current Sense Input. Connect an external sense resistor between SENSE+ and SENSE–. The differential voltage between SENSE+ and SENSE– is monitored by the onboard ADC with a full-scale sense voltage of 81.92mV. For more information www.linear.com/LTC4151 4151ff LTC4151 Pin Functions SHDN (LTC4151 Only): Shutdown Input. Internally pulled up to 6.3V. Pull this pin below 1V to force the LTC4151 into shutdown mode. Leave this pin open if unused. Block Diagram VIN: Supply Voltage Input. Accepts 7V to 80V. The voltage at this pin is monitored by the onboard ADC with a fullscale input range of 102.4V. SENSE+ must be connected to VIN for proper ADC readout. RS VIN 2k SENSE+ SENSE– 6.3V SHDN (LTC4151) ADR1 ADR0 5µA + INTERNAL POWER – DECODER 25X SHUTDOWN CONTROL SDAO/SDAO (LTC4151-1/ LTC4151-2) VREF = 2.048V 735k MUX 12-BIT ADC I2C/ REGISTERS 6V SDA/SDAI (LTC4151/ LTC4151-1) 15k 6V GND SCL ADIN 4151 BD Operation The LTC4151 accurately monitors high side current and voltages. This device accepts a wide range of input voltages from as low as 7V up to 80V and consumes less than 1.7mA quiescent current in normal operation. A shutdown mode is available with the LTC4151 to reduce the quiescent current to less than 300µA by pulling the SHDN pin below 1V. In default continuous scan mode after power-up, the onboard 12-bit analog-to-digital converter (ADC) continuously and sequentially measures the high side differential voltage between SENSE+ (Kelvin sense of VIN) and SENSE– (full-scale 81.92mV) through an internal sense amplifier, the input voltage VIN (full-scale 102.4V) through an internal voltage divider, and the voltage applied to the ADIN pin (full-scale 2.048V). The reference voltage of the ADC is internally set to 2.048V. The digital data obtained by the ADC is stored in the onboard registers. In snapshot mode, the LTC4151 can perform on-demand measurement of a selected voltage without the need of continuous polling by a master controller. The snapshot mode is enabled by programming the control register through the I2C interface. A status bit in the data register monitors the ADC’s conversion. When the conversion is completed, the 12-bit digital code of the measured voltage is held in the corresponding data registers. The LTC4151 provides an I2C interface to read the ADC data from the data registers and to program the control register. Two three-state pins, ADR0 and ADR1, are used to decode nine device addresses (see Table 1). The LTC4151 features a single SDA pin to handle both input data and output data, while the LTC4151-1/LTC4151-2 provide separate data in (SDAI) and data out (SDAO on the LTC4151-1 and SDAO on the LTC4151-2) pins to facilitate opto-isolation. 4151ff For more information www.linear.com/LTC4151 7 LTC4151 Applications Information The LTC4151 offers a compact complete solution for high side power monitoring. With a wide operating voltage range from 7V to 80V, this device is ideal for a variety of applications including consumer, automotive, industrial and telecom infrastructure. The simple application circuit as shown in Figure 1 provides monitoring of high side current with a 0.02W resistor (4.096A in full scale), input voltage (102.4V in full scale) and an external voltage (2.048V in full scale), all with an internal 12-bit resolution ADC. Data Converter The LTC4151 features an onboard, 12-bit ∆Σ A/D converter (ADC) that continuously monitors three voltages in the sequence of (VSENSE+ – VSENSE–) first, VIN second and VADIN third. The ∆Σ architecture inherently averages signal noise during the measurement period. The differential voltage between SENSE+ and SENSE– is monitored with an 81.92mV full scale and 20µV resolution that allows accurate measurement of the high side input current. SENSE+ is a Kelvin sense pin for the VIN pin and must be connected to VIN (see Figure 10) for proper ADC readout. The supply voltage at VIN is directly measured with a 102.4V full scale and 25mV resolution. The voltage at the uncommitted ADIN pin is measured with a 2.048V full scale and 0.5mV resolution that allows monitoring of any external voltage. The 12-bit digital code of each measured voltage is stored in two adjacent registers out of the six total data registers A through F, with the eight MSBs in the first register and the four LSBs in the second (Table 2). The data in registers A through F is refreshed at a frequency of 7.5Hz in continuous scan mode. Setting control register bit G4 (Table 6) invokes a test mode that halts updating of these registers so that they can be written to and read from for software testing. The data converter features a snapshot mode allowing users to make one-time measurements of a selected voltage (either the SENSE voltage, VIN voltage, or ADIN voltage). To enable snapshot mode, set control register bit G7 and write the 2-bit code of the desired ADC channel to G6 and G5 (Table 6) using a Write Byte command. When the Write Byte command is completed, the ADC measures the selected voltage and a Busy Bit in the LSB data register is set to indicate that the data is not ready. After completing the conversion, the ADC is halted and the Busy Bit is reset to indicate that the data is ready. To make another measurement of the same voltage or to measure another voltage, first disable the snapshot mode for the previous measurement by clearing control bit G7, then re-enable the snapshot mode and write the code of the desired voltage according to the procedure described above. The Busy Bit remains reset in the continuous scan mode. 0.02Ω VIN 7V TO 80V 3.3V VOUT SENSE+ SENSE– 2k LTC4151 VIN VDD 2k µ-CONTROLLER SHDN SCL SCL ADR1 SDA SDA ADR0 ADIN VADIN GND 4151 F01 GND Figure 1. Monitoring High Side Current and Voltages Using the LTC4151 4151ff 8 For more information www.linear.com/LTC4151 LTC4151 Applications Information I2C Interface The LTC4151 features an I2C-compatible interface to provide access to six ADC data registers and a control register for monitoring the measured voltages. Figure 2 shows a general data transfer format using the I2C. The LTC4151is a read-write slave device and supports SMBus Read Byte, Write Byte, Read Word and Write Word commands. The device also supports Read Page and Write Page commands that allow one to read or write more than two bytes of data. When using the Read Page and Write SDA a6 - a0 SCL 1-7 Page commands, the host need only to issue an initial register address and the internal register address pointer automatically increments by 1 after each byte of data is read or written. After the register address reaches 06h, it will be reset to 00h and continue the increment. Upon a Stop condition, the register address is reset to 00h. If desired, the Read Page and Write Page support can be disabled by clearing control register bit G3. The data formats for the above commands are shown in Figures 3 to 8. b7 - b0 8 9 1-7 b7 - b0 8 9 1-7 8 9 S P START CONDITION ADDRESS R/W ACK DATA ACK DATA ACK STOP CONDITION 4151 F02 Figure 2. General Data Transfer over I2C S ADDRESS W A COMMAND 1 1 0 a3:a0 0 0 X X X X X b2:b0 FROM MASTER TO SLAVE FROM SLAVE TO MASTER S A DATA A P 0 b7:b0 0 4151 F03 A: ACKNOWLEDGE (LOW) A: NOT ACKNOWLEDGE (HIGH) R: READ BIT (HIGH) ADDRESS W A COMMAND 1 1 0 a3:a0 0 0 X X X X X b2:b0 A DATA A DATA A P 0 b7:b0 0 b7:b0 0 4151 F04 W: WRITE BIT (LOW) S: START CONDITION P: STOP CONDITION Figure 4. LTC4151 Serial Bus SDA Write Word Protocol Figure 3. LTC4151 Serial Bus SDA Write Byte Protocol S ADDRESS W A COMMAND 1 1 0 a3:a0 0 0 X X X X X b2:b0 A DATA A DATA A ... DATA 0 b7:b0 0 b7:b0 0 ... b7:b0 0 A P S ADDRESS W A COMMAND 1 1 0 a3:a0 0 0 X X X X X b2:b0 A S ADDRESS 0 1 1 0 a3:a0 1 0 b7:b0 1 R A DATA A P 4151 F05 4151 F06 Figure 5. LTC4151 Serial Bus SDA Write Page Protocol S ADDRESS W A COMMAND 1 1 0 a3:a0 0 0 X X X X X b2:b0 Figure 6. LTC4151 Serial Bus SDA Read Byte Protocol A S ADDRESS 0 1 1 0 a3:a0 1 0 b7:b0 0 b7:b0 1 R A DATA A DATA A P 4151 F07 Figure 7. LTC4151 Serial Bus SDA Read Word Protocol S ADDRESS W A COMMAND 1 1 0 a3:a0 0 0 X X X X X b2:b0 A S ADDRESS R A DATA A DATA ... DATA A P 0 1 1 0 a3:a0 1 0 b7:b0 0 b7:b0 ... b7:b0 1 4151 F08 Figure 8. LTC4151 Serial Bus SDA Read Page Protocol 4151ff For more information www.linear.com/LTC4151 9 LTC4151 Applications Information Using Opto-Isolators with LTC4151-1 and LTC4151-2 Start and Stop Conditions The LTC4151-1/LTC4151-2 split the SDA line into SDAI (input) and SDAO (LTC4151-1 inverted output) or SDAO (LTC4151-2 output) for convenience of opto-coupling with a host controller that sits at a different ground level. When the I2C bus is idle, both SCL and SDA must remain in the high state. A bus master signals the beginning of a transmission with a Start condition by transitioning SDA from high to low while SCL stays high. When the master has finished communicating with the slave, it issues a Stop condition by transitioning SDA from low to high while SCL stays high. The bus is then free for another transmission. When using opto-isolators with the LTC4151-1, connect the SDAI to the output of the incoming opto-coupler and connect the SDAO to the anode of the outgoing optocoupler (see Figure 9). With the outgoing opto-coupler clamping SDAO and internal 6V (5.5V minimum) clamps on SDAI and SCL, the pull-up resistors on these three pins can be directly connected to VIN. In this way (with SDAO rather than conventional SDAO), the need for a separate low voltage supply for pull-ups is eliminated. Figure 11 shows the LTC4151-2 with high speed optocouplers for faster bus speeds. The LTC4151-2 has a noninverter SDAO output. Powered from VIN, the high voltage LT3010-5 low dropout regulator provides the supply for the opto-couplers as well as the bus lines pull-up. If the SDAI and SDAO on the master controller are not tied together, the ACK bit of the SDAO must be returned back to SDAI. Stuck-Bus Reset The LTC4151 I2C interface features a stuck-bus reset timer. The low conditions of the SCL and the SDA/SDAI pins are OR’ed to start the timer. The timer is reset when both SCL and SDA/SDAI are pulled high. If the SCL pin or the SDA/SDAI pin is held low for over 33ms, the stuck-bus timer will expire and the internal I2C state machine will be reset to allow normal communication after the stuck-bus condition is cleared. The stuck-bus timer can be disabled by clearing control register bit G2. RS 0.02Ω VIN 48V SENSE+ 3.3V SENSE– SCL R1 20k SDAI ADR1 SDA0 ADR0 ADIN GND R3 5.1k 8 VIN LTC4151-1 R2 20k VADIN MOCD207M 1 7 6 2 3 5 4 1 MOCD207M 8 R4 0.51k R5 0.51k R6 10k R7 10k SCL VDD µ-CONTROLLER SDA GND 4151 F09 2 3 7 6 4 5 Figure 9. Opto-Isolation of the I2C Interface Between LTC4151-1 and a Microcontroller (1.5kHz Data Rate of I2C is Limited by Slew Rate of Opto-Isolators) 4151ff 10 For more information www.linear.com/LTC4151 LTC4151 Applications Information I2C Device Addressing Nine distinct I2C bus addresses are configurable using the three-state pins ADR0 and ADR1, as shown in Table 1. Address bits a6, a5 and a4 are configured to (110) and the least significant bit is the R/W bit. In addition, the LTC4151 will respond to a mass write address (1100 110) b for writing to all LTC4151s, regardless of their individual address settings. Acknowledge The acknowledge signal is used for handshaking between the transmitter and the receiver to indicate that the last byte of data was received. The transmitter always releases the SDA line during the acknowledge clock pulse. The LTC4151 pulls the SDA line low on the 9th clock cycle to acknowledge receipt of the data. If the slave fails to acknowledge by leaving SDA high, then the master can abort the transmission by generating a Stop condition. When the master is receiving data from the slave, the master must pull down the SDA line during the clock pulse to indicate receipt of a data byte, and that another byte is to be read. After the last byte has been received the master will leave the SDA line high (not acknowledge) and issue a Stop condition to terminate the transmission. Write Protocol The master begins a write operation with a Start condition followed by the seven bit slave address and the R/W bit set to zero. After the addressed LTC4151 acknowledges the address byte, the master then sends a command byte which indicates which internal register the master wishes to write. The LTC4151 acknowledges this and then latches the lower three bits of the command byte into its internal register address pointer. The master then delivers the data byte and the LTC4151 acknowledges once more and latches the data into its internal register. If the master continues sending a second byte or more data bytes, as in a Write Word or Write Page command, the second byte or more data bytes will be acknowledged by the LTC4151, the internal register address pointer will increment automatically, and each byte of data will be latched into an internal register corresponding to the address pointer. The write operation terminates and the register address pointer resets to 00h when the master sends a Stop condition. Read Protocol The master begins a read operation with a Start condition followed by the seven bit slave address and the R/W bit set to zero. After the addressed LTC4151 acknowledges the address byte, the master then sends a command byte that indicates which internal register the master wishes to read. The LTC4151 acknowledges this and then latches the lower three bits of the command byte into its internal register address pointer. The master then sends a repeated Start condition followed by the same seven bit Table 1. LTC4151 Device Addressing* DESCRIPTION HEX DEVICE ADDRESS LTC4151 ADDRESS PINS BINARY DEVICE ADDRESS h a6 a5 Mass Write CC 1 1 0 CE 1 1 1 D0 1 1 2 D2 1 1 3 D4 1 1 4 D6 1 1 5 D8 1 1 6 DA 1 1 7 DC 1 1 8 DE 1 1 *H = Tie High; L = Tie to GND; NC = Open; X = Don’t Care a4 0 0 0 0 0 0 0 0 0 0 a3 0 0 1 1 1 1 1 1 1 1 a2 1 1 0 0 0 0 1 1 1 1 a1 1 1 0 0 1 1 0 0 1 1 a0 0 1 0 1 0 1 0 1 0 1 R/W 0 X X X X X X X X X ADR1 X H NC H NC NC L H L L ADR0 X L H H NC L H NC NC L 4151ff For more information www.linear.com/LTC4151 11 LTC4151 Applications Information Table 2. LTC4151 Register Address and Contents REGISTER ADDRESS* REGISTER NAME READ/WRITE 00h SENSE (A) R/W** ADC Current Sense Voltage Data (8 MSBs) 01h SENSE (B) R/W** ADC Current Sense Voltage Data (4 LSBs) 02h VIN (C) R/W** ADC VIN Voltage Data (8 MSBs) 03h VIN (D) R/W** ADC VIN Voltage Data (4 LSBs) 04h ADIN (E) R/W** ADC ADIN Voltage Data (8 MSBs) 05h ADIN (F) R/W** ADC ADIN Voltage Data (4 LSBs) 06h CONTROL (G) 07h Reserved R/W DESCRIPTION Controls ADC Operation Mode and Test Mode *Register address MSBs b7-b3 are ignored. **Writable if bit G4 is set. Table 3. SENSE Registers A (00h) and B (O1h)—Read/Write BIT NAME OPERATION A7:0, B7:4 SENSE Voltage Data 12-Bit Data of Current Sense Voltage with 20µV LSB and 81.92mV Full-Scale B3 ADC Busy in Snapshot Mode 1 = SENSE Being Converted; 0 = SENSE Conversion Completed. Not Writable B2:0 Reserved Always Returns 0. Not Writable Table 4. VIN Registers C (02h) and D (O3h)—Read/Write BIT NAME OPERATION C7:0, D7:4 VIN Voltage Data 12-Bit Data of VIN Voltage with 25mV LSB and 102.4V Full-Scale D3 ADC Busy in Snapshot Mode 1 = VIN Being Converted; 0 = VIN Conversion Completed. Not Writable D2:0 Reserved Always Returns 0, Not Writable Table 5. ADIN Registers E (04h) and F (O5h)—Read/Write BIT NAME OPERATION E7:0, F7:4 ADIN Voltage Data 12-Bit Data of Current Sense Voltage with 500µV LSB and 2.048V Full-Scale F3 ADC Busy in Snapshot Mode 1 = ADIN Being Converted; 0 = ADIN Conversion Completed. Not Writable F2:0 Reserved Always Returns 0, Not Writable Table 6. CONTROL Register G (06h)—Read/Write BIT NAME OPERATION G7 ADC Snapshot Mode Enable G6 ADC Channel Label for Snapshot Mode ADC Channel Label for Snapshot Mode Enables ADC Snapshot Mode; 1 = Snapshot Mode Enabled. Only the channel selected by G6 and G5 is measured by the ADC. After the conversion, the channel busy bit is reset and the ADC is halted. 0 = Snapshot Mode Disabled (ADC free running, Default). ADC Channel Label for Snapshot Mode G5 G6 0 0 1 G5 0 1 0 ADC CHANNEL SENSE (Default) VIN ADIN G4 Test Mode Enable G3 Page Read/Write Enable Test Mode Halts ADC Operation and Enables Writes to ADC Registers; 1 = Enable Test Mode, 0 = Disable Test Mode (Default) Enables Page Read/Write; 1 = Enable I2C Page Read/Write (Default), 0 = Disable I2C Page Read/Write G2 Stuck-Bus Timer Enable Enables I2C Stuck-Bus Reset Timer; 1 = Enable Stuck-Bus Timer (Default), 0 = Disable Stuck-Bus Timer G1:0 Reserved Always Returns 0, Not Writable 4151ff 12 For more information www.linear.com/LTC4151 LTC4151 Applications Information address with the R/W bit now set to one. The LTC4151 acknowledges and sends the contents of the requested register. The transmission terminates when the master sends a Stop condition. If the master acknowledges the transmitted data byte, as in a Read Word command, the LTC4151 will send the contents of the next register. If the master acknowledges the second data byte and each of the following (if more) data bytes, as in a Read Page command, the LTC4151 will keep sending out each data byte in the register that corresponds to the incrementing register pointer. The read operation terminates and the register address pointer resets to 00h when the master sends a Stop condition. stays at a reasonable temperature. Using 0.03" per amp or wider is recommended. Note that 1oz copper exhibits a sheet resistance of about 530µW per square. VIN ILOAD RS SENSE+ VIN ADR1 SENSE– GND LTC4151 ADR0 Layout Considerations A Kelvin connection between the sense resistor RS and the LTC4151 is recommended to achieve accurate current sensing (Figure 10). The minimum trace width for 1oz copper foil is 0.02" per amp to make sure the trace ILOAD GND 4151 F10 Figure 10. Recommended Layout for Kelvin Connection R1 0.02Ω VIN 7V TO 80V VIN VOUT + SENSE VIN ADIN SENSE– LTC4151-2 SDAO ADIN ADR1 SDAI ADR0 SCL GND 1 IN OUT LT3010-5 C7 1µF 5 SHDN SENSE 2 100V GND 4 ISO1 PS9817-2 8 C6 1µF R8 1k R3 10k R4 10k VCC 1 8 7 2 GND 5 8 1 7 VCC 6 5 GND 5V C4 0.1µF R12 1k R11 1k R14 10k R13 10k 2 ISO_SDA 3 ISO_SCL 4 4151 F11 ISO2 PS9817-2 Figure 11. LTC4151-2 I2C Opto-Isolation Interface with High Speed Opto-Couplers 4151ff For more information www.linear.com/LTC4151 13 LTC4151 Typical Application Temperature Monitoring with an NTC Thermistor While Measuring Load Current and LTC4151 Supply Current 0.2Ω VIN 48V VISHAY 2381 615 4.104 100k AT 25°C 1% SENSE+ SENSE – 250mA LOAD VIN SCL I2C 40.2k 1% LTC4151 ADIN SDA ADR1 1.5k 1% GND ADR0 4151 TA02 T(°C) = 58.82 • (NADIN /NVIN – 0.1066), 20°C < T < 60°C. NADIN AND NVIN ARE DIGITAL CODES MEASURED BY THE ADC AT THE ADIN AND VIN PINS, RESPECTIVELY. LTC4151-1 Monitors Current and Input Voltage of a –48V System and Interfaces with a Microcontroller (1.5kHz Data Rate of I2C is Limited by Slew Rate of Opto-Isolators) RS 0.02Ω RTN SENSE+ 3.3V SENSE– SCL R1 20k SDAI ADR1 SDA0 ADR0 ADIN GND R3 5.1k 8 VIN LTC4151-1 R2 20k VADIN MOCD207M 1 7 6 2 3 5 4 1 MOCD207M 8 R4 0.51k R5 0.51k R6 10k R7 10k SCL VDD µ-CONTROLLER SDA GND 4151 TA04 –48V 2 3 7 6 4 5 4151ff 14 For more information www.linear.com/LTC4151 LTC4151 Package Description Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. DD Package 10-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1699 Rev C) R = 0.125 TYP 6 0.40 ± 0.10 10 0.70 ±0.05 3.55 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 3.00 ±0.10 (4 SIDES) 1.65 ± 0.10 (2 SIDES) PIN 1 NOTCH R = 0.20 OR 0.35 × 45° CHAMFER PIN 1 PACKAGE TOP MARK OUTLINE (SEE NOTE 6) 0.25 ± 0.05 5 0.75 ±0.05 0.200 REF 0.50 BSC 2.38 ±0.05 (2 SIDES) 0.00 – 0.05 1 (DD) DFN REV C 0310 0.25 ± 0.05 0.50 BSC 2.38 ±0.10 (2 SIDES) BOTTOM VIEW—EXPOSED PAD RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2). CHECK THE LTC WEBSITE DATA SHEET FOR CURRENT STATUS OF VARIATION ASSIGNMENT 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE MS Package 10-Lead Plastic MSOP (Reference LTC DWG # 05-08-1661 Rev F) 0.889 ±0.127 (.035 ±.005) 5.10 (.201) MIN 3.20 – 3.45 (.126 – .136) 3.00 ±0.102 (.118 ±.004) (NOTE 3) 0.50 0.305 ±0.038 (.0197) (.0120 ±.0015) BSC TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) 10 9 8 7 6 3.00 ±0.102 (.118 ±.004) (NOTE 4) 4.90 ±0.152 (.193 ±.006) DETAIL “A” 0.497 ±0.076 (.0196 ±.003) REF 0° – 6° TYP GAUGE PLANE 1 2 3 4 5 0.53 ±0.152 (.021 ±.006) DETAIL “A” 0.18 (.007) SEATING PLANE 0.86 (.034) REF 1.10 (.043) MAX 0.17 – 0.27 (.007 – .011) TYP 0.50 (.0197) BSC NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 0.1016 ±0.0508 (.004 ±.002) MSOP (MS) 0213 REV F 4151ff For more information www.linear.com/LTC4151 15 LTC4151 Package Description Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. S Package 16-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610 Rev G) .386 – .394 (9.804 – 10.008) NOTE 3 .045 ±.005 .050 BSC 16 N 14 13 12 11 10 9 N .245 MIN .160 ±.005 .150 – .157 (3.810 – 3.988) NOTE 3 .228 – .244 (5.791 – 6.197) 1 .030 ±.005 TYP 15 2 3 N/2 N/2 RECOMMENDED SOLDER PAD LAYOUT .010 – .020 × 45° (0.254 – 0.508) .008 – .010 (0.203 – 0.254) 1 2 3 4 5 .053 – .069 (1.346 – 1.752) NOTE: 1. DIMENSIONS IN .014 – .019 (0.355 – 0.483) TYP 7 8 .004 – .010 (0.101 – 0.254) 0° – 8° TYP .016 – .050 (0.406 – 1.270) 6 .050 (1.270) BSC S16 REV G 0212 INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 4. PIN 1 CAN BE BEVEL EDGE OR A DIMPLE 4151ff 16 For more information www.linear.com/LTC4151 LTC4151 Revision History (Revision history begins at Rev C) REV DATE DESCRIPTION C 11/10 Added H-grade information PAGE NUMBER 2, 3 Revised order of Pin Functions section and added information to SDAI pin description 6 Added diode and 2k resistor to Block Diagram 7 Added information to Application Information section 10 D 7/12 Changed part number in Pin Configuration section from LT4151 to LTC4151 2 E 11/12 Added –48V application schematic 14 F 3/14 Increased VADR(H) MAX limit and decreased VADR(L) MIN limit 4 4151ff Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representaFor more information www.linear.com/LTC4151 tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. 17 LTC4151 Typical Application High Side Current, Input Voltage and Open Fuse Monitoring with a Single LTC4151 VIN1 48V F1 D1 F2 D2 RS 0.02Ω VIN2 48V D3 D4 R1 150k R2 301k SENSE+ SENSE– VIN SCL V+ I2C LTC4151 LOAD ADR1 ADIN R3 3.4k SDA V– ADR0 GND GND 4151 TA03 CONDITION RESULT NADIN ≥ 1.375 • NVIN Normal Operation 0.835 • NVIN ≤ NADIN < 1.375 • NVIN F2 is Open 0.285 • NVIN ≤ NADIN < 0.835 • NVIN F1 is Open (Not Responding) Both F1 and F2 are Open VIN1 AND VIN2 ARE WITHIN 20% APART. NADIN AND NVIN ARE DIGITAL CODES MEASURED BY THE ADC AT THE ADIN AND VIN PINS, RESPECTIVELY. Related Parts PART NUMBER DESCRIPTION COMMENTS LT2940 Power and Current Monitor Four-Quadrant Multiplication, ±5% Power Accuracy, 4V to 80V Operation LTC2945 Wide Range I2C Power Monitor 0V to 80V Input Range, 2.7V to 80V Supply Range, Shunt Regulator, 12-Bit ADC with ±0.75% TUE LTC2451 16-Bit I2C Ultra Tiny Delta Sigma ADC Single-Ended Input, 0 to VCC Input Range, 60Hz Output Rate, 3mm × 2mm DFN-8 Package LTC2453 16-Bit I2C Ultra Tiny Delta Sigma ADC Differential Input, ±VCC Input Range, 60Hz Output Rate, 3mm × 2mm DFN-8 Package LTC2970 Power Supply Monitor and Margining Controller 14-Bit ADC Monitoring Current and Voltages, Supplies from 8V to 15V Controller with ADC and I2C 8-Bit ADC Monitoring Current and Voltages, Supplies from 2.9V to 15V TM LTC4215 Positive Hot Swap LTC4260 Positive High Voltage Hot Swap Controller with ADC and I2C 8-Bit ADC Monitoring Current and Voltages, Supplies from 8.5V to 80V LTC4261/ LTC4261-2 Negative High Voltage Hot Swap Controller with ADC and I2C 10-Bit ADC Monitoring Current and Voltages, Supplies from –12V LTC6101/ LTC6101HV High Voltage, High Side Current Sense Amplifier in SOT-23 Package Supplies from 4V to 60V (LTC6101) and 5V to 100V (LTC6101HV) 4151ff 18 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 For more information www.linear.com/LTC4151 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com/LTC4151 LT 0314 REV F • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2008