TS821 1.225V micropower shunt voltage reference Features 1.225V typical output voltage Ultra low operating current: 45A maximum at 25C High precision 25C L +/- 2% (standard version) SOT23-3L +/- 1% (A grade) (Plastic micropackage) +/- 0.5% (B grade) High stability when used with capacitive loads Pin connections Industrial temperature range: -40C to +85C (Top view) 120ppm/C maximum temperature coefficient Applications Computers Instrumentation Battery chargers Switch mode power supply Battery operated equipment Description The TS821 is a low power shunt voltage reference providing a stable 1.225V output voltage over the industrial temperature range (-40C to +85C). Availabe in SOT23-3 surface mount package, it can be designed in applications where space saving is critical. The low operating current is a key advantage for power restricted designs. In addition, the TS821 is very stable and can be used in a broad range of application conditions. July 2007 Rev 2 1/9 www.st.com 9Absolute maximum ratings and operating conditions TS821 1 Absolute maximum ratings and operating conditions Table 1. Absolute maximum ratings (AMR) Symbol Parameter Value Unit I Reverse breakdown current 20 mA k I Forward current 10 mA f (1) P Power dissipation SOT23-3 360 mW d T Storage temperature -65 to +150 C stg (2) Human body model (HBM) 2kV ESD (3) Machine model (MM) 200 V T Lead temperature (soldering, 10 seconds) 260 C lead 1. P is calculated with T = 25C and T = 150C and R = 340C/W for the SOT23-3L package. d amb j thja 2. Human body model: 100pF discharged through a 1.5k resistor between two pins of the device, done for all couples of pin combinations with other pins floating. 3. Machine model: a 200pF cap is charged to the specified voltage, then discharged directly between two pins of the device with no external series resistor (internal resistor < 5), done for all couples of pin combinations with other pins floating. Table 2. Operating conditions Symbol Parameter Value Unit I Minimum operating current 45 A min I Maximum operating current 12 mA max T Operating free air temperature range -40 to +85 C oper 2/9