NJU7664 PRELIMINARY VOLTAGE CONVERTER FOR GaAs FET ■ GENERAL DESCRIPTION The NJU7664 is a voltage converter for GaAs FET, which contains CR oscillation circuit and dual operational amplifiers. The voltage converter is a circuit operated by the charge pumping system, and it generates the negative voltage from the positive power supply. Furthermore the charge pumping capacitor is incorporated. Both of two operational amplifiers with the gain resistance which is set up at -OdB output the negative voltage by the inverted input voltage. The NJU7664 realizes to operate the GaAs FET requiring the negative gate biassing. ■ PACKAGE OUTLINE ■ FEATURES • Voltage Converter Operated With The Charge Pumping System • Charge Pump Capacitor Incorporated • CR Oscillation Circuit Incorporated • Wide Operating Voltage VDD = 2.7V to 5.2V • Output Voltage 0 to -4.0V (VDD = 5.2V) • Low Operating Current 1.25mA MAX(VDD = 2.7V) • Stand-by Function • C-MOS Technology • Package Outline VSP-8 ■ PIN CONFIGURATION NJU7664R ■ BLOCK DIAGRAM Ver.2003-07-18 -1- NJU7664 ■ TERMINAL DESCRIPTION No. SYMBOL 1 STB 2 3 4 5 6 7 8 VIN1 NC VOUT1 GND VOUT2 VIN2 VDD FUNCTION Stand-by input terminal H : oscillating L : stop oscillating Positive voltage input terminal 1 No connection (Electrically open) Negative voltage output terminal 1 Ground terminal Negative voltage output terminal 2 Positive voltage input terminal 2 Power supply terminal ■ FUNCTIONAL DESCRIPTION • Voltage Converter The voltage converter is a circuit designed for generating the negative voltage (-VDD) from the positive power supply (VDD). Because the voltage efficiency is 85% (TYP.), the negative voltage (-VDD x 0.85) is output typically. This converter uses the charge pumping system which consists of capacitors and switches. VDD GND = 0V VDD 2 x VDD VOUT = -VDD • Operational Amplifier As the input and the feedback resistor of the operational amplifier is incorporated, an uni-multiple inverting amplifier is constructed. • Stand-by Function The NJU7664 turns to the stand-by mode when the STB terminal level is set to "L". During the stand-by mode, the voltage converter outputs GND voltage and the the operating current is lower as the oscillator stop operating. -2- Ver.2003-07-18 NJU7664 ■ ABSOLUTE MAXIMUM RATINGS PARAMETER (Ta = 25ºC) SYMBOL RATINGS UNIT Supply Voltage VDD 5.5 V Input Voltage VIN GND -0.5 to VDD + 0.5 V VOUT -5.0 V Output Voltage Power Dissipation PD 320 mW Operating Temperature Range Topr -30 to + 85 ºC Storage Temperature Range Tstg -40 to +125 ºC Note1) Decoupling capacitor should be connected between VDD and GND due to the stabilized operation for the voltage converter. ■ ELECTRICAL CHARACTERISTICS ·DC CHARACTERISTICS PARAMETER Operating Voltage (VDD = 2.7V, GND = 0V, Ta = 25°C) SYMBOL CONDITIONS VDD MIN. TYP. MAX. UNIT 2.7 - 5.2 V IDD1 ISI1 = -100µA, ISI2 = -1µA - - 1.25 mA IDD2 No load - - 1.0 mA IDD3 STB = L - - 1.0 µA High Level Input Voltage VIH STB terminal 0.8VDD VDD V Low Level Input Voltage VIL STB terminal GND 0.2VDD V Input Current 1 IIN1 STB terminal, Vi = VDD or GND Oscillation Frequency fOSC Operating Current Input Voltage VIN VIN1, VIN2 Terminals - - 1.0 µA - 4.0 - MHz VDD = 2.7V 0 - 2.0 V VDD = 5.2V 0 - 4.0 V VDD = 2.7V VIN = 2.0V - - 10.0 µA O VDD = 5.2v VIN = 4.0V - - 20.0 µA P VDD = 2.7V ISI = -100µA -2.0 - 0 V VDD = 2.7V ISI = -100µA -4.0 - 0 V Input Current 2 A M P Output Voltage Output Source Current Output Sink Current Output Ripple Current Gain Error Ver.2003-07-18 IIN2 VOUT VIN1, VIN2 Terminals VOUT1, VOUT2 Terminals ISO VOUT1, VOUT2 Terminals 5.0 - - µA ISI VOUT1, VOUT2 Terminals - - -100 µA Total of VOUT1, VOUT2 Term. - - -105 µA VRR1 ISI = -100µA, CL = 0.1µF - 0.4 - mV VRR2 ISI = -5µA, CL = 0.1µF - 0.4 - mV -10 - 10 % ISITOTAL GER -3- NJU7664 ■ APPLICATION CIRCUITS [CAUTION] The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights. -4- Ver.2003-07-18