Product Details

describe:

The LM77 is a digital temperature sensor and thermal window comparator with an I 2 C serial bus interface. The LM77's window comparator architecture simplifies the design of ACPI (Advanced Configuration and Power Interface) compliant personal computer temperature control systems. The open-drain interrupt (INT) output activates whenever the temperature exceeds a programmable window, while a separate critical temperature alarm (T_CRIT_A) output activates when the temperature exceeds a programmable critical limit. The INT output can operate in comparator or event mode, while the T_CRIT_A output operates in comparator mode only.

The host can program upper and lower window limits and critical temperature limits. Programmable hysteresis as well as fault queues can be used to minimize false trips. Two pins (A0, A1) can be used for address selection. The AD7891BP-2 sensor powers up with default thresholds of 2°CT HYST, 10°CT LOW, 64°CT HIGH, and 80°C T_CRIT.

The 3.0V to 5.5V supply voltage range, serial bus interface, 9-bit + sign output, and full-scale range of over 128°C make the LM77 ideal for a variety of applications. These include thermal management and protection applications in personal computers, electronic test equipment, office electronics, automotive and HVAC applications.

characteristic:

● Window comparison simplifies the design of ACPI-compliant temperature monitoring and control.

●Serial bus interface

● Independent open-drain outputs for interrupt and critical temperature shutdown

● Shutdown mode to minimize power consumption

●Up to 4 LM77s can be connected to a single bus

9-bit + sign output; full-scale reading over 128°C

●SOIC and VSSOP 8-pin packages

Main Specifications:

●Power supply voltage 3.0V to 5.5V

● Power supply current

○ Working 250 μA (typ) 500 μA (max)

○ Shutdown 5 μA (typ)

●Temperature accuracy

○-10°C to 65°C, ±1.5°C (max)

○-25°C to 100°C, ±2°C (max)

○-55°C to 125°C, ±3°C (max)

parameter:

Local Sensor Accuracy (Max) (+/- C): 1.5

Type: local

Operating temperature range (°C): -55 to 125

Power supply voltage (Min) (V): 3

Interface type: I2C, SMBus

Power supply voltage (Max) (V): 5.5

Supply Current (Max) (uA): 500

Temperature Resolution (Max) (Bits): 10

Remote channel (#): 0

Address: 4