PRECISION 1.25 VOLT MICROPOWER VOLTAGE REFERENCE ZREF12 ISSUE 2 - MARCH 1998 DEVICE DESCRIPTION FEATURES • The ZREF12 uses a bandgap circuit design to achieve a precision micropower voltage reference of 1.24 volts. The device is available in a small outline surface mount package, ideal for applications where space saving is important, as well as packages for through hole requirements. • • • • • The ZREF12 design provides a stable voltage without an external capacitor and is stable with capacitive loads. The ZREF12 is recommended for operation between 50µA and 5mA and so is ideally suited to low power and battery powered applications. • • • Excellent performance is maintained to an absolute maximum of 25mA, however the rugged design and 20 volt processing allows the reference to withstand transient effects and currents up to 200mA. Superior switching capability allows the device to reach stable operating conditions in only a few microseconds. Small outline SO8 and TO92 style packages No stabilising capacitor required Typical TC 30ppm/°C Typical slope resistance 0.65Ω ± 1% tolerance Industrial temperature range (Military temperature range available on request) Operating current 50µA to 5mA Transient response, stable in less than 10µs Alternative package options and tolerances available APPLICATIONS • • • • • • SCHEMATIC DIAGRAM V R G nd 4-267 Battery powered and portable equipment. Metering and measurement systems. Instrumentation. Precision power supplies. Test equipment. Data acquisition systems ZREF12 ABSOLUTE MAXIMUM RATING Reverse Current Forward Current Operating Temperature Storage Temperature Power Dissipation (Tamb=25°C) E-Line, 3 pin (TO92) 500mW E-Line, 2 pin (TO92) 500mW SO8 625mW 25mA 25mA -40 to 85°C -55 to 125°C ELECTRICAL CHARACTERISTICS TEST CONDITIONS (Unless otherwise stated) Tamb=25°C SYMBOL PARAMETER CONDITIONS VR Reverse Breakdown Voltage IR=150µA IMIN Minimum Operating Current IR Recommended Operating Current TC † Average Reverse Breakdown Voltage Temp. Co. IR(min) to IR(max) Slope Resistance LIMITS MIN RS § TYP MAX 1.228 1.24 1.252 30 0.05 30 0.5 EN Wideband Noise Voltage IR = 150µA f = 100Hz to 10kHz 60 RS = µA 5 mA 90 ppm/°C 1 µV(rms) Reverse Current (µA) 60 Note: VR(max) - VR(min) is the maximum deviation in reference voltage measured over the full operating temperature range. § 50 Ω IR = 1mA f = 100Hz IAC= 0.1 IR (VR(max)−VR(min)) x 1000000 VR x (T(max)−T(min)) V Ω Reverse Dynamic Impedance TC = 1 UNITS 0.65 2 ZR † TOL. % VR Change(IR (min) to IR (max)) 50 40 30 C 5° C =8 5° TA =2 °C TA 40 =TA 20 10 0 IR (max) − IR (min) 0 0.2 0.4 0.6 0.8 1.0 1.2 Reverse Voltage (V) Reverse Characteristics 4-268 1.4 ZREF12 1.4 1.27 1.2 1.26 Reference voltage (V) Forward Voltage (V) TYPICAL CHARACTERISTICS 1.0 0.8 0.6 0.4 IR=150µA to 5mA 1.25 1.24 1.23 1.22 1.21 0.2 0.1 1 10 100 -40 1000 -20 0 20 40 60 80 Temperature (°C) Forward Current (mA) Forward Characteristics Temperature Drift 1000 100 Slope resistance (Ω) Slope resistance (Ω) 1.0 TA=-40°C TA=25°C 0.5 TA=85°C IR=150µA 10 IR=1mA IR=5mA 1 0.1 0.01 0 0.1 1 0.1 Reference Current (mA) 100 Slope Resistance v Frequency 1.5 1.5 1.0 VR - (V) VR - (V) 10 Frequency (kHz) Slope Resistance v Current INPUT 58K 0.5 1.0 OUTPUT 0 0 10 10 0 0 1 2 3 INPUT 1K8 OUTPUT 0.5 VIN - (V) VIN - (V) 1 10 4 0 0 Time (µs) 2 4 6 Time (µs) Transient Response (IR=150µ µA) Transient Response (IR=5mA) 4-269 8 ZREF12 CONNECTION DIAGRAMS E-Line, 2 pin Package Suffix – Y E-Line, 3 pin,Rev Package Suffix – R Bottom View Bottom View – Pin 3 floating or connected to pin 1 SO8 Package Suffix – N8 Top View ORDERING INFORMATION Part No Tol% Package Partmark ZREF12 1 E-Line † ZREF12 ZREF12Z 1 E-Line * ZREF12 ZREF12D 1 SO8 ZREF12 * E-Line 3 pin Reversed † E-Line 2 pin 4-270