LQH31CN100

ZXLD1615 ADJUSTABLE DC-DC BOOST CONVERTER WITH INTERNAL SWITCH IN TSOT23-5 DESCRIPTION The ZXLD1615 is a PFM inductive boost converter designed to provide output voltages of up to 28V from a 2.5V to 5.5V input supply. The ZXLD1615 includes the output switch and peak current sense resistor, and can provide up to 10mA output current at maximum output voltage. Higher current is available at lower output voltages. Quiescent current is typically 60 A and a shutdown function is provided to reduce this current to less than 100nA in the 'off' state. Nominal output voltage can be set up to a maximum of 28V by two external resistors and can be adjusted to lower values by a PWM control signal applied to the 'Enable' pin. Depending upon the control frequency, the PWM signal will provide either continuous (low ripple) or gated control. The PWM filter components are contained within the chip. Minimum output voltage is determined by the input supply. The device is assembled in a low profile TSOT23-5 pin package. ADVANCED FEATURES • Internal 30V NDMOS switch • True analog output voltage control via PWM with internal filter APPLICATIONS • LCD and OLED bias • Cellular / mobile phones • Digital cameras • PDAs • LCD modules • Varactor and PIN diode bias • Palmtop computers FEATURES • Low profile TSOT23-5 pin package • Internal PWM filter for adjustable output • High efficiency (85% typ) • Wide input voltage range: 2.5V to 5.5V • Up to 250mA output current at 5V • Low quiescent current: (60 A typ) • 100nA maximum shutdown current • Up to 1MHz switching frequency • Low external component count TYPICAL APPLICATION CIRCUIT PINOUT TOP VIEW ISSUE 3 - AUGUST 2004 1 SEMICONDUCTORS ZXLD1615 ABSOLUTE MAXIMUM RATINGS (Voltages to GND unless otherwise stated) Input voltage (VIN) 7V LX output voltage (VLX) Switch output current (ILX) Power dissipation (PD) Operating temperature (TOP) Storage temperature (TST) Junction temperature (Tj MAX) 30V 500mA 300mW -40 to 85°C -55 to 150°C 125°C ELECTRICAL CHARACTERISTICS: (Test conditions: VIN=VEN=3V, TAMB=25°C unless otherwise stated(1)) Symbol V IN I IN Parameter Input voltage Supply current Quiescent Shutdown V FB f LX T OFF T ON (2) I LXpk R LX I LX(leak) V ENH V ENL I ENL I ENH TEN(hold)(3) T /T FB pin control voltage Operating frequency LX output ‘OFF’ time LX output ‘ON’ time Switch peak current limit Switch 'On' resistance Switch leakage current V LX =20V 1.5 L=10 H , V OUT =28V, 5mA load 320 1.75 1 V IN 0.4 -100 1 120 20 100 µA V V nA A µs % L=10 H , V OUT =28V, 5mA load 350 VEN = VIN, ILX = 0, Output not switching V EN = 0V 0.98 600 500 5 60