ZXLD1615 ADJUSTABLE DC-DC BOOST CONVERTER WITH INTERNAL SWITCH IN TSOT23-5 DESCRIPTION The ZXLD1615 is a PFM inductive boost converter Nominal output voltage can be set up to a maximum designed to provide output voltages of up to 28V of 28V by two external resistors and can be adjusted from a 2.5V to 5.5V input supply. to lower values by a PWM control signal applied to the Enable pin. Depending upon the control The ZXLD1615 includes the output switch and peak frequency, the PWM signal will provide either current sense resistor, and can provide up to 10mA continuous (low ripple) or gated control. The PWM output current at maximum output voltage. Higher filter components are contained within the chip. current is available at lower output voltages. Minimum output voltage is determined by the input Quiescent current is typically 60 A and a shutdown supply. function is provided to reduce this current to less The device is assembled in a low profile TSOT23-5 than 100nA in the off state. pin package. ADVANCED FEATURES Internal 30V NDMOS switch APPLICATIONS True analog output voltage control via PWM LCD and OLED bias with internal filter Cellular / mobile phones FEATURES Digital cameras Low profile TSOT23-5 pin package PDAs Internal PWM filter for adjustable output LCD modules High efficiency (85% typ) Varactor and PIN diode bias Wide input voltage range: 2.5V to 5.5V Palmtop computers Up to 250mA output current at 5V Low quiescent current: (60 A typ) TYPICAL APPLICATION CIRCUIT 100nA maximum shutdown current Up to 1MHz switching frequency Low external component count PINOUT TOP VIEW ISSUE 3 - AUGUST 2004 SEMICONDUCTORS 1ZXLD1615 ABSOLUTE MAXIMUM RATINGS (Voltages to GND unless otherwise stated) Input voltage (V)7V IN LX output voltage (V ) 30V LX Switch output current (I ) 500mA LX Power dissipation (PD) 300mW Operating temperature (T ) -40 to 85C OP Storage temperature (T ) -55 to 150C ST Junction temperature (Tj ) 125C MAX (1) ELECTRICAL CHARACTERISTICS: (Test conditions: V =V =3V, T =25C unless otherwise stated ) IN EN AMB Symbol Parameter Conditions Min Typ Max Units V Input voltage 2.5 5.5 V IN I Supply current IN Quiescent V =V ,I = 0, Output not switching 60 100 A EN IN LX Shutdown V =0V <10 100 nA EN V FB pin control voltage 0.98 1.07 V FB f Operating frequency L=10 H, V =28V, 5mA load 600 kHz LX OUT T LX output OFF time 350 500 ns OFF (2) T LX output ON time 5s ON I Switch peak current limit L=10 H, V =28V, 5mA load 320 mA LXpk OUT R Switch On resistance 1.75 LX I Switch leakage current V =20V 1 A LX(leak) LX V EN pin high level Input voltage Device active 1.5 V V ENH IN V EN pin low level Input voltage Device in shutdown 0.4 V ENL I EN pin low level input current V =0V -100 nA ENL EN I EN pin high level input current V =V 1 A ENH EN IN (3) T EN pin turn off delay V switched from high to low 120 s EN(hold) EN T/T PWM duty cycle range at 10kHz<f< 100kHz, V =V 20 100 % ENH IN EN input for dc output voltage control f Internal PWM low pass filter 4 kHz LPF cut-off frequency A Filter attenuation f=30kHz 52.5 dB LPF NOTES: 1 Production testing of the device is performed at 25C. Functional operation of the device over a 40C to +85C temperature range is guaranteed by design, characterization and process control. 2 Nominal on time (TONnom ) is defined by the input voltage (V ), coil inductance (L) and peak current (I ) according to the expression: IN LXpkdc T = I x L/V +200ns ONnom LX(pkdc) IN 3 This is the time for which the device remains active after the EN pin has been asserted low. This delay is necessary to allow the output to be maintained during dc PWM mode operation. 4 The maximum PWM signal frequency during this mode of operation should be kept as low as possible to minimize errors due to the turn-off delay ISSUE 3 - AUGUST 2004 SEMICONDUCTORS 2