LTC4151 pin FuncTions SHDN (LTC4151 Only): Shutdown Input. Internally pulled VIN: Supply Voltage Input. Accepts 7V to 80V. The voltage up to 6.3V. Pull this pin below 1V to force the LTC4151 at this pin is monitored by the onboard ADC with a full- into shutdown mode. Leave this pin open if unused. scale input range of 102.4V. SENSE+ must be connected to VIN for proper ADC readout. block DiagraM RS VIN SENSE+ SENSE– 6.3V SHDN ADR1 ADR0 2k (LTC4151) 5µA + – DECODER INTERNAL 25X SHUTDOWN POWER CONTROL SDAO/SDAO (LTC4151-1/ V LTC4151-2) REF = 2.048V 735k I2C/ REGISTERS SDA/SDAI MUX 12-BIT ADC 6V (LTC4151/ LTC4151-1) 15k SCL 6V GND ADIN 4151 BD operaTion The LTC4151 accurately monitors high side current and In snapshot mode, the LTC4151 can perform on-demand voltages. This device accepts a wide range of input volt- measurement of a selected voltage without the need of ages from as low as 7V up to 80V and consumes less continuous polling by a master controller. The snapshot than 1.7mA quiescent current in normal operation. A mode is enabled by programming the control register shutdown mode is available with the LTC4151 to reduce through the I2C interface. A status bit in the data register the quiescent current to less than 300µA by pulling the monitors the ADC’s conversion. When the conversion is SHDN pin below 1V. completed, the 12-bit digital code of the measured voltage In default continuous scan mode after power-up, the is held in the corresponding data registers. onboard 12-bit analog-to-digital converter (ADC) continu- The LTC4151 provides an I2C interface to read the ADC ously and sequentially measures the high side differential data from the data registers and to program the control voltage between SENSE+ (Kelvin sense of VIN) and SENSE– register. Two three-state pins, ADR0 and ADR1, are (full-scale 81.92mV) through an internal sense amplifier, used to decode nine device addresses (see Table 1). The the input voltage VIN (full-scale 102.4V) through an internal LTC4151 features a single SDA pin to handle both input voltage divider, and the voltage applied to the ADIN pin data and output data, while the LTC4151-1/LTC4151-2 (full-scale 2.048V). The reference voltage of the ADC is provide separate data in (SDAI) and data out (SDAO on internally set to 2.048V. The digital data obtained by the the LTC4151-1 and SDAO on the LTC4151-2) pins to ADC is stored in the onboard registers. facilitate opto-isolation. 4151ff For more information www.linear.com/LTC4151 7 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Package Description Revision History Typical Application Related Parts