EUP2618

Preliminary EUP2618 Triple Adjustable Output TFT-LCD DC-DC Converters DESCRIPTION The EUP2618 triple-output DC-DC converter provides the regulated voltages required by active-matrix, thin-film transistor (TFT) liquid-crystal displays (LCDs). One high-power DC-DC converter and two low-power charge pumps convert the 3.3V to 5V input supply voltage into three independent output voltages. The primary 1.2MHz DC-DC converter generates a boosted output voltage (VMAIN) up to 18V using ultra-small inductors and ceramic capacitors. The low-power control circuitry and the low on-resistance (0.2Ω) of the integrated power MOSFET allows efficiency up to 92%. The dual charge pumps independently regulate one positive output (VPOS) and one negative output (VNEG). These low-power outputs use external diode and capacitor stages to regulate output voltages up to 40V and down to -40V. For EUP2618, the supply sequence is VMAIN first, VNEG next, and finally VPOS. The EUP2618 soft-starts each supply as soon as the previous supply finishes. The EUP2618 are available in the ultra-thin TSSOP-16 package. FEATURES 1.2MHz Current-Mode PWM Boost Regulator Up to 18V Main High-Power Output 2.1A, 0.2Ω Power MOSFET 92% High Efficiency Dual Adjustable Charge-Pump Outputs Up to 40V Positive Output Down to -40V Negative Output Internal Power-up Sequencing 2.5V to 5.5V Input Range 0.1µA Shutdown Current 0.7mA Quiescent Current Internal Soft-Start Power-Ready Output Ultra-Small External Components Thin TSSOP-16 Package RoHS Compliant and 100% Lead (Pb)-Free APPLICATIONS TFT Active-Matrix LCD Displays Passive-Matrix LCD Displays PDAs Digital Still Cameras Camcorders Typical Application Circuit Figure 1. DS2618 Ver0.1 Nov. 2007 1 Preliminary Block Diagram EUP2618 Figure 2. DS2618 Ver0.1 Nov. 2007 2 Preliminary Pin Configurations Package Type Pin Configurations EUP2618 TSSOP-16 Pin Description PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 NAME RDY FB COMP IN GND REF FBP FBN SHDN DESCRIPTION Active-Low, Open-Drain Output. Indicates all outputs are ready. The on-resistance is 125Ω (typ). Main Boost Regulator Feedback Input. Regulates to 1.25V nominal. Connect feedback resistive divider to analog ground (GND). Main Boost Compensation Network Connection. Supply Input. 2.5V to 5.5V input range. Bypass with a 0.1µF capacitor between IN and GND, as close to the pins as possible. Analog Ground. Connect to power ground (PGND) underneath the IC. Internal Reference Bypass Terminal. Connect a 0.22µF capacitor from this terminal to analog ground (GND). External load capability to 100µA. Positive Charge-Pump Regulator Feedback Input. Regulates to 1.25V nominal. Connect feedback resistive divider to analog ground (GND). Negative Charge-Pump Regulator Feedback Input. Regulates to 0V nominal. Active-Low Logic-Level Shutdown Input. Connect SHDN to IN for normal operation. Negative Charge-Pump Driver Output. Output high level is VSUPN, and low level is TGND. Negative Charge-Pump Driver Supply Voltage. Bypass to TGND with a 0.1µF capacitor. Positive Charge-Pump Driver Output. Output high level is VSUPP, and low level is TGND. Positive Charge-Pump Driver Supply Voltage. Bypass to TGND with a 0.1µF capacitor. Power Ground of Charge-Pumps. Main Boost Regulator Power MOSFET n-Channel Drain. Connect output diode and output capacitor as close to PGND as possible. Power Ground of Main Boost. DRVN SUPN DRVP SUPP TGND LX PGND DS2618 Ver0.1 Nov. 2007 3 Preliminary Ordering Information Order Number Package Type Marking EUP2618 Operating Temperature range EUP2618QIR1 TSSOP-16 xxxxx EUP2618 -40 °C to 85°C EUP2618 □□□ □ Lead Free Code 1: Lead Free 0: Lead Packing R: Tape & Reel Operating temperature range I: Industry Standard Package Type Q: TSSOP DS2618 Ver0.1 Nov. 2007 4 Preliminary Absolute Maximum Ratings EUP2618 IN to GND ---------------------------------------------------------------------------- -0.3V to 6V DRVN to GND ---------------------------------------------------------- -0.3V to (VSUPN +0.3V) DRVP to GND ----------------------------------------------------------- -0.3V to (VSUPP +0.3V) PGND ,TGND to GND --------------------------------------------------------------------- ±0.3V RDY ,SUPP,SUPN to GND -------------------------------------------------------- -0.3V to 14V LX to GND --------------------------------------------------------------------------- -0.3V to 19V COMP, SHDN ,REF, FB ,FBN, FBP to GND ------------------------ -0.3V to (VIN +0.3V) Operating Temperature --------------------------------------------------------- -40°C to 85°C Junction Temperature ------------------------------------------------------------------- 150°C Storage Temperature ----------------------------------------------------------- -65°C to150°C Lead Temp (Soldering, 10sec) --- --------------------------------------------------260°C Electrical Characteristics (Specfications in standard type face are for TA =25℃ and those with boldface type apply over the full Operating Temperature Range (TA=-40℃ to 85℃). VIN=3.3V, VSUPP=VSUPN=10V ,GND=PGND=TGND=0, unless otherwise noted.) EUP2618 Parameter Conditions Unit Min. Typ. Max. Operating Power Input Supply Voltage Range VIN Under Voltage Lockout Falling Rising VFB=VFBP=1.4V, VFBN=0V , not switching VFB=1.1V, VFBP=1.4V, VFBN=0V switching V SHDN =GND 15℃ Hysteresis IVREF=100uA IVREF=100uA, VIN=2.5~5V IVREF=0~100uA 1.22 VFB=1.25V 2.5V