19-5881; Rev 1; 12/11 TION KIT EVALUA BLE AVAILA Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications The MAX17135 is a complete power-management IC for E-paper displays that provides source- and gate-driver power supplies, a high-speed VCOM amplifier, and a temperature sensor. The source-driver power supplies consist of a boost converter and an inverting buck-boost converter that generates +15V (up to +17V) and -15V (up to -17V), respectively. Both source-driver power supplies can deliver up to 200mA. The positive source-driver supply regulation voltage (VPOS) can be set either by using an I2C interface or by connecting an external resistordivider. The negative source-driver supply voltage (VNEG) is always tightly regulated to -VPOS within Q50mV. The gate-driver power supplies consist of regulated charge pumps that generate +22V (up to +40V) and -20V (up to -40V) and can deliver up to 20mA each. Features S Four Regulated Output Voltages for Source- and Gate-Driver Power Supplies S VPOS + VNEG = ±50mV Tracking Accuracy S Measures Internal and Remote Diode Temperature Sensors S True Shutdown on All Outputs S 2.7V to 5.5V IN Supply Voltage Range S Controlled Inrush Current During Soft-Start S I2C Serial Interface for Temperature Read, Power Output Enable, POS Voltage Regulation Set-Point Adjustment, Power-Up/Power-Down Sequencing Adjustment, and Fault Monitoring Simplified Operating Circuit The IC features a VCOM amplifier output whose output voltage is controlled by an internal 8-bit digital-to-analog converter (DAC). The DAC is programmable through an I2C interface and allows small-voltage-step sizes per DAC step. The IC includes a temperature sensor that provides the ability to read the internal IC temperature and an external panel temperature with the use of an external temperature-sensing diode. Temperature output data is supplied through I2C. The device is available in a space-saving, 32-pin TQFN package and is specified over the -40NC to +85NC extended temperature range. PGVDD DP LXP VGVDD FBP DGVDD DGVEE VGVEE -40NC to +85NC 32 TQFN-EP* +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. NEG VNEG MAX17135 Ordering Information PIN-PACKAGE VPOS PGVEE FBNG TEMP RANGE HVINP POS DN E-Book Readers MAX17135ETJ+ PGND FBPG Applications PART 2.7V TO 5.5V INPUT IN HVINN 2.7V TO 5.5V INPUT INN REF LXN CEN CONTROLLER EN POK FLT VCOM VDD I2C BUS VVCOM DXP GND DXN SCL SDA EP ________________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. MAX17135 General Description MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications ABSOLUTE MAXIMUM RATINGS IN, EN, CEN, VDD, SDA, SCL, INN, FLT to GND....-0.3V to +6V FBPG, FBNG, FBP, DXP, DXN, REF to GND...............................................-0.3V to (VIN + 0.3V) POK to GND.............................................-0.3V to (VVDD + 0.3V) LXP to PGND..........................................................-0.3V to +20V PGVDD, POS to GND............................-0.3V to (VHVINP + 0.3V) LXN to PGND........................... (VHVINN - 0.3V) to (VINN + 0.3V) PGVEE, NEG to GND........................... (VHVINN - 0.3V) to +0.3V DP to PGND..........................................-0.3V to (VHVINP + 0.3V) DN to PGND......................................... (VHVINN - 0.3V) to +0.3V DGVDD to GND......................................................-0.3V to +42V HVINN to PGND.....................................................-20V to +0.3V DGVEE to GND......................................................-42V to +0.3V DGVDD to HVINN................................................................ +60V VCOM to GND ..................................... (VHVINN - 0.3V) to +0.3V PGND to GND ......................................................-0.3V to +0.3V LXP, LXN, INN, PGND RMS Current Rating ........................1.6A Continuous Power Dissipation (multilayer board) TQFN (derate 24.9mW/NC above TA = +70NC)............ 1990mW Operating Temperature Range........................... -40NC to +85NC Junction Temperature......................................................+150NC Storage Temperature Range............................. -65NC to +150NC Lead Temperature (soldering, 10s).................................+300NC Soldering Temperature (reflow).......................................+260NC Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VIN = 3.6V, Typical Operating Circuit of Figure 2, VHVINP = 15V, VNEG = -15V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25NC.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 5.5 V 2.55 2.65 INPUT SUPPLIES AND REFERENCE IN Voltage Range IN UVLO Threshold 2.7 VIN rising 2.45 IN UVLO Hysteresis IN Quiescent Current 100 EN = GND and the SHUTDOWN bit in the Configuration register = 1 4 10 EN = GND and the SHUTDOWN bit in the Configuration register = 0 0.8 1.5 VEN = 3.6V, no switching, SHUTDOWN bit in the Configuration register = 0 2 3.5 mA VEN = 3.6V, switching, SHUTDOWN bit in the Configuration register = 0 3 VDD Input Voltage VDD UVLO Threshold VDD Quiescent Current V mV 1.6 FA 5.5 V 1.2 1.5 V EN = GND 4 10 Normal mode 4 10 1.250 1.262 1.0 1.2 VDD rising, hysteresis = 150mV REF Output Voltage No load REF UVLO Threshold REF rising REF UVLO Hysteresis 1.238 FA V V 100 mV REF Load Regulation 0 < IREF < 100FA 10 mV REF Line Regulation 2.7V < VIN < 5.5V 2 mV 2 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications (VIN = 3.6V, Typical Operating Circuit of Figure 2, VHVINP = 15V, VNEG = -15V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25NC.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS STEP-UP REGULATOR Output Voltage Range VHVINP VPOS FBP = GND Operating Frequency Oscillator Maximum Duty Cycle Output Voltage Resolution FBP = GND POS Output Regulation Error FBP = GND, VINN = 2.7V to 5.5V, 1mA < IPOS < 200mA FBP Regulation Voltage VIN 17 5 17 850 1000 1150 91 95 98 4 -2 1.238 FBP Load Regulation 1mA < IPOS < 200mA FBP Line Regulation VIN = 2.7V to 5.5V FBP Input Bias Current VFBP = 1.25V, TA = +25NC FBP Internal Divider Enable Threshold kHz % Bits +2 % 1.262 V -1 % -0.08 %/V 125 200 nA FBP rising, hysteresis = 10mV 25 50 mV LXP On-Resistance ILXP = 0.2A 250 500 mI LXP Leakage Current EN = GND, VLXP = 18V, TA = +25NC 20 FA 2.1 A LXP Current Limit Duty cycle = 80% 50 1.250 V 1.5 Soft-Start Period 1.8 5 ms INVERTING REGULATOR INN Input Voltage Range 2.7 INN Quiescent Current 5.5 EN = GND 10 No switching 10 Switching Output Voltage Range VHVINN Oscillator Maximum Duty Cycle FA 3 mA -17 Operating Frequency V V 850 1000 1150 kHz 91 95 98 % VPOS + VNEG Regulation Voltage VINN = 2.7V to 5.5V, 1mA < INEG < 200mA, IPOS = no load, VNEG R -15V, TA = 0NC to +85NC -50 +50 mV VPOS + VNEG Regulation Voltage VINN = 2.7V to 5.5V, 1mA < INEG < 200mA, IPOS = no load -70 +70 mV LXN On-Resistance INN to LXN, ILXN = 0.2A 500 mI LXN Leakage Current VLXN = VHVINN = -18V, TA = +25NC 20 FA 2.4 A LXN Current Limit Duty cycle = 85% 250 1.8 Soft-Start Period 2.1 5 ms POSITIVE CHARGE-PUMP REGULATOR PGVDD Operating Voltage Range VPGVDD 7 HVINP-DP Current Limit 150 Oscillator Frequency 400 VHVINP V 600 kHz mA 500 3 MAX17135 ELECTRICAL CHARACTERISTICS (continued) MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications ELECTRICAL CHARACTERISTICS (continued) (VIN = 3.6V, Typical Operating Circuit of Figure 2, VHVINP = 15V, VNEG = -15V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25NC.) PARAMETER SYMBOL CONDITIONS FBPG Regulation Voltage FBPG Line Regulation VHVINP = 11V to 16V FBPG Load Regulation 0mA < IGVDD < 100mA FBPG Input Bias Current DP On-Resistance High VFBPG = 1.25V, TA = +25NC IDP = 100mA DP On-Resistance Low IDP = -100mA MIN TYP MAX 1.238 1.250 1.262 0.05 Soft-Start Period V %/V 0.04 -50 UNITS % +50 nA 3 6 I 1.5 3 10 I ms NEGATIVE CHARGE-PUMP REGULATOR PGVEE Operating Voltage Range VPGVEE VHVINN HVINN-DN Current Limit 150 Oscillator Frequency 400 FBNG Regulation Voltage -12 FBNG Line Regulation VNEG = -11V to -16V FBNG Load Regulation 0mA < IGVEE < 100mA FBNG Input Bias Current VFBNG = 0V, TA = +25NC DN On-Resistance High IDN = 100mA DN On-Resistance Low IDN = -100mA -7 V 500 600 kHz 0 +12 mA 0.05 -0.03 -50 Soft-Start Period mV %/V % +50 nA 3 6 I 1.5 3 I 10 ms VCOM Input Supply Range VHVINN -5 V 30 µA HVINP Shutdown Current VEN = GND and the SHUTDOWN bit in the Configuration register = 1, VHVINP = 3.6V 10 HVINP Quiescent Current VHVINP = 15V, VEN = 3.6V, Configuration register = 0 0.8 mA HVINN Quiescent Current VHVINN = -15V, VEN = 3.6V, Configuration register = 0 2.0 mA VCOM Voltage High IVCOM = 5mA VCOM Voltage Low VCOM Load Regulation VCOM Output Current VCOM High Impedance Leakage 4 IVCOM = -5mA 0mA < IVCOM < 30mA, sourcing, DVR register = 7Fh -25 VHVINN + 50 VHVINN + 25 -1.6 -0.6 mV mV % 0mA < IVCOM < 30mA, sinking, DVR register = 7Fh 0.3 Sourcing 70 Sinking 70 CEN = GND, TA = +25NC -50 1.3 mA 1 FA Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications (VIN = 3.6V, Typical Operating Circuit of Figure 2, VHVINP = 15V, VNEG = -15V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25NC.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS SEQUENCE SWITCHES POS Output Range VPOS POS On-Resistance Tracks HVINP VIN (HVINP - POS), IPOS = 100mA 0.9 POS Charge Current Limit 250 POS Discharge Resistance 200 POS Soft-Start Charge Time NEG Output Range NEG On-Resistance VNEG Tracks HVINN mA 340 600 250 200 NEG Soft-Start Charge Time V 0.6 1 340 600 I mA 10 (HVINP - PGVDD), IPGVDD = 30mA (HVINN - PGVEE), IPGVEE = 30mA I ms -17 (HVINN - NEG), INEG = 100mA NEG Discharge Resistance PGVEE On-Resistance V I 10 NEG Charge Current Limit PGVDD On-Resistance 17 1.3 I ms 4 7 I 1.5 3 I 40 V 1200 1600 I DGVDD AND DGVEE DGVDD Input Voltage Range 7 DGVDD Discharge Resistance 800 DGVEE Input Voltage Range -40 -7 V DVGEE Discharge Resistance 800 1200 1600 I VCOM Discharge Resistance 100 170 300 I FAULT PROTECTION HVINP Fault Threshold VHVINP falling FBP Fault Threshold VFBP falling 75 80 85 % 0.95 1.00 1.05 V FBPG Fault Threshold VFBPG falling 0.95 HVINN Fault Threshold VHVINN rising -VHVINP x 0.85 1.00 1.05 V -VHVINP x 0.8 -VHVINP x 0.75 V FBNG Fault Threshold VFBNG rising 200 250 300 mV Feedback Fault Timer Thermal Shutdown Hysteresis = 15NC 50 ms 160 NC TEMPERATURE SENSOR Temperature Resolution External Diode Temperature Error Monotonicity guaranteed Diode Source Current Diode Source Current Ratio Bits 0.5 NC TA = 0NC to +85NC -4 +4 TA = -40NC to +125NC -8 +8 External Conversion Time Conversion Rate 8 LSB 60 NC ms Register 0Fh = 100b 1 Register 0Fh = 111b 8 Conv/s VDXP = 1.5V - high level 90 100 110 VDXP = 1.5V - low level 9.0 10 11.0 VDXP = 1.5V 9.5 10 10.5 FA A/A 5 MAX17135 ELECTRICAL CHARACTERISTICS (continued) MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications ELECTRICAL CHARACTERISTICS (continued) (VIN = 3.6V, Typical Operating Circuit of Figure 2, VHVINP = 15V, VNEG = -15V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25NC.) PARAMETER SYMBOL CONDITIONS DXN Source Voltage MIN TYP MAX UNITS 0.4 0.7 0.85 V Diode Short-Circuit Threshold VDXN = 0.7V, VDXP - VDXN 20 65 110 mV Diode Open-Circuit Threshold VDXN = 0.7V, VDXP - VDXN 1.6 1.9 2.2 V PROGRAMMABLE VCOM CALIBRATOR VCOM-DAC Voltage Resolution 8 VCOM-DAC Differential Nonlinearity Monotonic over temperature Bits -1 +1 LSB VCOM-DAC Accuracy VCOM_set = 0x7F. TA = 0NC to +85NC -1.5 +1.5 LSB VCOM-DAC Accuracy VCOM_set = 0x7F. TA = -40NC to +85NC -2.5 +2.5 LSB +4 LSB VCOM-DAC Accuracy Other setting Memory Program Voltage HVINP rising, hysteresis = 250mV POS Settling Time To Q0.5 LSB error band -4 6.95 7.1 7.25 20 V Fs Memory Write Cycles 30 Times Memory Write Time 110 ms CONTROL LOGIC Input Low Voltage EN, CEN Input High Voltage EN, CEN Input Impedance EN, CEN = 3.6V POK Logic-High Output Voltage IPOK = 0.5mA POK Logic-Low Output Voltage IPOK = -0.5mA FLT Leakage Current V/FLT = 5.5V, TA = +25NC FLT Output Low Voltage I/FLT = 6mA 0.3 x VDD 0.7 x VDD V V 1 MI VDD - 0.4 V 0.4 V 1 FA 0.4 V I2C INTERFACE Input Capacitance SDA, SCL Input Low Voltage VIL SDA, SCL Input High Voltage VIH SDA, SCL SDA Sink Current VSDA = 0.4V 5 pF 0.3 x VDD 0.7 x VDD V 6 mA SCL Frequency fSCL SCL High Time tHIGH 600 ns SCL Low Time tLOW 1300 ns 6 DC V 400 kHz Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications (VIN = 3.6V, Typical Operating Circuit of Figure 2, VHVINP = 15V, VNEG = -15V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25NC.) PARAMETER SYMBOL CONDITIONS MIN SDA, SCL Rise Time tR CBUS = total bus line capacitance (pF) (Note 2) SDA, SCL Fall Time tF CBUS = total bus line capacitance (pF) (Note 2) START Hold Time tHD;STA START Setup Time tSU;STA Data Input Hold Time Data Input Setup Time STOP Setup Time Bus Free Time TYP UNITS 300 ns 20 + 10 x CBUS 300 ns 600 ns 600 ns tHD;DAT 0 ns tSU;DAT 100 ns tSU;STO 600 ns tBUF 1300 ns Input Spike Suppression SDA Reset Low Time MAX 20 + 10 x CBUS tTIMEOUT 10% of SDA to 90% of SCL SDA, SCL (Note 2) 250 ns (Notes 1, 2) 60 ms Note 1: H olding the SDA line low for a time greater than tTIMEOUT causes the device to reset SDA to the IDLE state of the serial bus communication (SDA set high). Note 2: Guaranteed by design, not production tested. Note 3: All devices are 100% tested at TA = +25°C. Limits over temperature are guaranteed by design. tHD;STA tR tLOW SCL tHIGH tF tHD;DAT SDA tSU;STO tSU;DAT tSU;STA tBUF VIH VIL Figure 1. Timing Definitions Used in the Electrical Characteristics 7 MAX17135 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (TA = +25°C, unless otherwise noted.) -0.10 OUTPUT ERROR (%) IVIN (uA) 5.0 VIN = 3.6V VPOS = 15V FBP = GND 4.5 4.0 3.5 3.0 OUTPUT ERROR (%) VDD = 3.3V, TEMP SENSOR SHUTDOWN = 1 POS LINE REGULATION 0 MAX17135 toc02 5.5 POS LOAD REGULATION 0 MAX17135 toc01 6.0 -0.20 -0.30 VPOS = 15V IPOS = 100mA FBP = GND -0.05 MAX17135 toc03 TOTAL INPUT SUPPLY STANDBY CURRENT vs. IN SUPPLY VOLTAGE -0.10 -0.15 -0.40 2.5 -0.20 -0.50 2.0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 0 6.0 50 100 150 2.7 3.4 4.1 4.8 INPUT VOLTAGE (V) POS LOAD-TRANSIENT RESPONSE (50mA TO 150mA) VPOS + VNEG LOAD REGULATION MAX17135 toc04 VPOS (AC-COUPLED) 100mV/div 0mV 100µs/div OUTPUT ERROR (mV) 0mA MAX17135 toc05 0 IPOS 100mA/div -5 -10 ILX1 1A/div 0A -15 VIN = 3.6V VPOS = 15V FBP = GND CPOS-GND = 3 x 4.7µF -20 VPOS = 15V VNEG = -15V VIN = 3.6V FBP = GND 0 25 50 75 100 125 150 175 200 LOAD CURRENT (mA) NEG LOAD-TRANSIENT RESPONSE (50mA TO 150mA) VPOS + VNEG LINE REGULATION MAX17135 toc07 MAX17135 toc06 1.0 -1.0 -3.0 INEG 100mA/div 0mA VNEG 100mV/div (AC-COUPLED) 0mV -5.0 -7.0 -9.0 -11.0 ILX2 1A/div 0A VPOS = 15V VNEG = -15V IPOS = INEG = 0mA -13.0 -15.0 2.5 8 200 LOAD CURRENT (mA) VIN (V) OUTPUT ERROR (mV) MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications 3.0 3.5 4.0 4.5 VIN (V) 5.0 5.5 6.0 100µs/div VIN = 3.6V VNEG = -VPOS = -15V CNEG-GND = 3 x 4.7µF 5.5 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications POWER-DOWN SEQUENCE OF ALL SUPPLY OUTPUTS MAX17135 toc08 GVDD LOAD REGULATION MAX17135 toc09 0V 0V 0V 0V 0V 0V 0V POS 10V/div NEG 10V/div GVEE 20V/div VIN = 3.6V VHVINP = 15V VGVDD = 22V 0.30 GVDD 20V/div OUTPUT ERROR (%) 0V 0.35 MAX17135 toc10 POWER-UP SEQUENCE OF ALL SUPPLY OUTPUTS 0.25 0.20 0.15 0.10 0.05 0V EN 2V/div 0V 20ms/div 20ms/div 0 10 1 100 LOAD CURRENT (mA) GVEE LOAD REGULATION -0.10 -0.15 VIN = 3.6V VHVINP = 15V VCOM AT NO LOAD = -1.77V -0.05 OUTPUT ERROR (%) OUTPUT ERROR (%) MAX17135 toc11 VIN = 3.6V VHVINN = -15V VGVEE = -20V -0.05 0 -0.10 MAX17135 toc12 VCOM LOAD REGULATION 0 -0.15 -0.20 -0.25 -0.30 -0.20 -0.35 -0.25 -0.40 10 0 100 5 10 LOAD CURRENT (mA) NEG EFFICIENCY vs. LOAD CURRENT 25 30 VIN = 3.6V VNEG = 15V POS EFFICIENCY vs. LOAD CURRENT 80 70 60 VIN = 3.6V VPOS = 15V FBP = GND 90 EFFICIENCY (%) EFFICIENCY (%) 20 100 MAX17135 toc13 100 90 15 LOAD CURRENT (mA) MAX17135 toc14 1 80 70 60 50 50 40 0 50 100 150 LOAD CURRENT (mA) 200 0 50 100 150 200 LOAD CURRENT (mA) 9 MAX17135 Typical Operating Characteristics (continued) (TA = +25°C, unless otherwise noted.) Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications POS VCOM GND N.C. N.C. CEN FLT TOP VIEW NEG MAX17135 Pin Configuration 24 23 22 21 20 19 18 17 16 HVINN 25 EN LXN 26 15 DXN INN 27 14 DXP 13 SDA 12 SCL 11 VDD 10 DN 9 PGVEE HVINP 28 MAX17135 LXP 29 PGND 30 FBP 31 EP + 6 7 8 FBNG FBPG 5 REF PGVDD 4 DGVEE 3 POK 2 DGVDD 1 DP IN 32 TQFN Pin Description 10 PIN NAME 1 DP FUNCTION 2 PGVDD 3 FBPG 4 DGVDD 5 POK 6 DGVEE 7 REF 8 FBNG Feedback Input for GVEE 9 PGVEE Supplies the HVINN Voltage to the Negative Charge Pump for the GVEE Output. Connect as shown in Figure 2. Regulated Charge-Pump Driver for GVDD. Connect to flying capacitor. Supplies the HVINP Voltage for the Positive Charge Pump. Connect as shown in Figure 2. Feedback Input for GVDD GVDD Discharge. Connect the output of the positive charge pump to DGVDD as shown in Figure 2. Power-OK. Driven high when the outputs of the gate- and source-driver power supplies are all in regulation. GVEE Discharge. Connect the output of the negative charge pump to DGVEE as shown in Figure 2. Voltage Reference. Bypass to GND with a minimum 0.1FF ceramic capacitor. 10 DN Regulated Charge-Pump Driver for GVEE. Connect to flying capacitor. 11 VDD Logic Supply Input for the I2C. Bypass to GND through a minimum 0.1FF capacitor. 12 SCL I2C Serial Clock Input 13 SDA I2C Serial Data Input/Output 14 DXP External Temperature-Sensing Diode Anode Connection. Bypass DXP to DXN with a 2200pF ceramic capacitor. Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications PIN NAME 15 DXN FUNCTION External Temperature-Sensing Diode Cathode Connection 16 EN Enable Pin. Logic-high initiates power-up sequencing. Logic-low initiates power-down sequencing. 17 FLT Fault Indicator. Open-drain output goes low during a fault condition. 18 CEN VCOM Enable. Logic-high enables VCOM output. Logic-low causes the load on the VCOM output to be discharged. 19, 20 N.C. No Connection 21 GND Analog GND 22 VCOM VCOM Output 23 POS Positive Source-Driver Output Voltage 24 NEG Negative Source-Driver Output Voltage 25 HVINN 26 LXN DC-DC Inverting Converter Inductor/Diode Connection 27 INN Inverting Converter Power Input. 2.7V to 5.5V. Bypass to PGND with a minimum 10FF ceramic capacitor. 28 HVINP 29 LXP 30 PGND 31 FBP Input Power for the NEG Voltage Rail. Connect the output of the inverting converter to this pin. Input Power for the POS Voltage Rail. Connect the output of the step-up converter to this pin. Step-Up Converter Inductor/Diode Connection Power Ground Feedback Pin for HVINP Output. Connect FBP to GND to set the HVINP regulation voltage to +15V. With FBP connected to ground, VHVINP can be changed through I2C after power-up by changing the value stored in the HVINP register. Alternatively, connect an external resistor-divider midpoint to the FBP pin to set the HVINP regulation voltage. 32 IN Power Input. Bypass to GND through a minimum 1FF capacitor. — EP Exposed Pad. Connect exposed pad to ground. 11 MAX17135 Pin Description (continued) MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications C16 1µF 25V D4 C15 0.1µF 25V R6 10I IN C1 1µF 10V PGVDD DP D1 C3 4.7µF 25V PGND FBPG C14 1µF 25V R5 20kI FBP HVINP DGVDD C13 0.1µF 25V D3 VGVEE = -20V 20mA DGVEE POS MAX17135 DN C12 4.7µF 50V C11 1µF 25V R2 806kI NEG PGVEE FBNG VPOS = +15V 200mA C4 4.7µF 25V C17 4.7µF 25V C5 4.7µF 25V VNEG = -VPOS C18 200mA 4.7µF 25V HVINN INN C6 10µF 6.3V R3 49.9kI REF R7 0.5I LXN C7 4.7µF 25V L2 4.7µH CEN EN POK FLT VCOM R1 100kI Figure 2. Typical Operating Circuit 12 VCOM = -0.5V TO -3.05V, 70mA (ADJUSTABLE IN 10mV STEPS) DXP VDD C9 0.1µF I2C BUS C19 4.7µF 25V 2.7V TO 5.5V INPUT D2 C10 0.1µF CONTROLLER L1 4.7µF 2.7V TO 5.5V INPUT LXP R4 332kI VGVDD = +22V 20mA C2 10µF 6.3V Q1 C8 2200pF GND SCL SDA EP DXN C20 4.7µF 25V Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications MAX17135 2.7V TO 5.5V INPUT IN PGVDD LXP DP 1MHz PWM BST REGULATED CHARGE PUMP PGND FBPG VGVDD FBP DGVDD HVINP DGVEE REGULATED CHARGE PUMP DN VGVEE POS SOFTSTART POS VPOS PGVEE NEG NEG SOFTSTART FBNG VNEG HVNN 1.25V REF INN CEN EN CONTROLLER POK FLT VDD I2C BUS SCL ENABLE CONTROL AND FAULT LOGIC I2C INTERFACE SDA POWER RAIL OUTPUT CONTROL 1MHz PWM INV 2.7V TO 5.5V INPUT LXN MAX17135 NONVOLATILE MEMORY GND DXP TEMP ADC VCOM REGISTER AND DAC VCOM TO VCOM BACKPLANE DXN INTERNAL DIODE TEMPERATURE SENSOR Figure 3. Functional Diagram 13 MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications Typical Operating Circuit The IC’s typical operating circuit (Figure 2) generates Q15V source-driver supplies and +22V and -20V gatedriver supplies for E-paper displays. The input voltage range for the IC is from 2.7V to 5.5V. Figure 3 shows the functional diagram. Table 1 lists recommended components and Table 2 lists contact information for component suppliers. Detailed Description Source-Driver Power Supplies The source-driver power supplies consist of a boost converter and an inverting buck-boost converter that generate +15V (+17V max) and -15V (-17V max), respectively, and can deliver up to 200mA. The positive source-driver power supply’s regulation voltage (VPOS) can be set using the external resistor-divider network shown in Figure 2, or can be programmed through the I2C interface connecting FBP to GND before power-up. Table 1. Component List DESIGNATION C2, C6 C3, C4, C5, C7, C17–C20 DESCRIPTION 10FF Q10%, 6.3V X7R ceramic capacitors (0805) TDK C2012X7R0J106K 4.7FF Q10%, 25V X7R ceramic capacitors (1206) Murata GRM31CR71E475KA88L D1, D2 30V, 1A single Schottky diodes (SOD123) ON Semiconductor MBR130T1 D3, D4 Dual small-signal diodes (SOT23) Fairchild MMBD4148SE L1, L2 4.7FH, 1.5A, 45mI inductors TOKO A915AY-4R7M Q1 40V npn transistor (SOT23) Fairchild MMBT3904 Table 2. Component Suppliers SUPPLIER WEBSITE Fairchild Semiconductor www.fairchildsemi.com Murata Electronics North America, Inc. www.murata-northamerica.com ON Semiconductor www.onsemi.com TDK Corp. www.component.tdk.com TOKO America, Inc. www.tokoam.com 14 The negative source-driver supply voltage (VNEG) is automatically tightly regulated to -VPOS within Q50mV. VNEG cannot be adjusted independently of VPOS. Gate-Driver Power Supplies The positive gate-driver power supply (GVDD) generates +22V (+40V max) and the negative gate-driver power supply (GVEE) generates -20V (-40V max). Both supplies can supply up to 20mA current. The GVDD and GVEE regulation voltages are both set by using the external resistor-divider networks shown in Figure 2. VCOM Amplifier The IC features a negative output VCOM amplifier whose voltage is programmed through an I2C interface. An internal 8-bit digital-to-analog converter (DAC) allows for a wide VCOM output range of -0.5V to -3.05V and a 10mV change per DAC step. The user can store the DAC setting in nonvolatile memory. On power-up, the nonvolatile memory sets the DAC to the last stored setting. Temperature Sensor The IC includes a temperature sensor that reads the internal IC temperature and the external panel temperature with the use of an external temperature-sensing diode. Temperature output data is supplied through I2C. An analog-to-digital converter (ADC) converts the temperature data to 9 bits, two’s-complement format and stores the conversion results in separate temperature registers. Fault Protection The IC has robust fault and overload protection. If any of the GVEE, NEG, POS, or GVDD outputs fall more than 80% (typ) below their intended regulation voltage for more than 50ms (typ), or if a short-circuit condition occurs on any output for any duration, then all outputs latch off and FLT is asserted low. The fault condition is set in the Fault register, which can be read through the I2C interface. True Shutdown The IC completely disconnects the loads from the input when in shutdown mode. In most boost converters, the external rectifying diode and inductor form a DC current path from the battery to the output. This can drain the battery even in shutdown if a load was connected at the boost-converter output. The device has an internal switch at POS. When this switch turns off during shutdown, there is no DC path from the input to POS. Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications The device supports an I2C-compatible, 2-wire digital interface. SDA is the bidirectional data line and SCL is the clock line of the 2-wire interface corresponding, respectively, to the SDA and SCL lines of the I2C bus. Write to a register by writing the device address byte, a data pointer byte, and a data byte. Read from the IC in one of two ways: if the location latched in the Pointer register is set from the previous read, the new read consists of a device address byte, followed by retrieving the corresponding number of data bytes. If the Pointer register needs to be set to a new address, perform a read operation by writing the device address byte, pointer byte, repeat start, and the device address byte again with the read bit. An inadvertent 8-bit read from a 16-bit register, with the D7 bit low, can cause the device to stop in a state where the SDA line is held low. Ordinarily, this would prevent any further bus communication until the master sends nine additional clock cycles or SDA goes high. At that time, a STOP condition resets the device. If the additional clock cycles are not generated by the master, the IC bus resets and unlocks after the bus timeout period has elapsed. Power-On/Power-Off Sequencing and Timing The IC allows for flexible power-up/power-down sequencing and timing of the source-driver and gate-driver power supplies (GVEE, NEG, POS, and GVDD). Toggling the EN pin from low to high or setting the EN bit in the enable register to 1 initiates an adjustable preset powerup sequence. Toggling the EN pin from high to low or setting the EN bit in the Enable register to 0 initiates an adjustable preset power-down sequence. The powerup/power-down sequence and timing between rails are determined by the user’s values programmed into the Timing registers through I2C. The desired sequence and timing between rails contained in the Timing registers can also be stored in the nonvolatile memory, such that desired timing information is loaded into the Timing registers at power-up. The device uses the read and write protocols shown in Figure 4. BYTE READ FROM PRESET POINTER LOCATION MSB START 1 MSB LSB 0 0 1 0 0 0 SLAVE ACK 1 d7 LSB d6 d5 SLAVE ADDRESS d4 d3 d2 d1 p2 p1 d0 STOP DATA BYTE POINTER SET FOLLOWED BY IMMEDIATE BYTE READ 1 MSB LSB MSB START 0 0 1 0 0 0 0 SLAVE ACK 0 0 SLAVE ADDRESS p4 p3 p0 MSB LSB LSB 0 SLAVE ACK REPEAT START 1 0 0 POINTER BYTE 1 0 0 0 1 SLAVE ACK d7 LSB d6 d5 SLAVE ADDRESS d4 d3 d2 d1 d2 d1 d0 STOP DATA BYTE WORD READ FROM PRESET POINTER LOCATION MSB START 1 MSB LSB 0 0 1 0 0 0 1 SLAVE ACK d7 SLAVE ADDRESS MSB LSB d6 d5 d4 d3 d2 d1 d0 MASTER ACK d7 MOST SIGNIFICANT DATA BYTE LSB d6 d5 d4 d3 d2 d1 d0 STOP LEAST SIGNIFICANT DATA BYTE POINTER SET FOLLOWED BY IMMEDIATE WORD READ MSB START 1 MSB LSB 0 0 1 0 0 0 0 MASTER ACK 0 MSB LSB 0 0 SLAVE ADDRESS p4 p3 p2 p1 p0 SLAVE ACK REPEAT START 1 MSB LSB 0 POINTER BYTE 0 1 0 0 0 1 SLAVE ACK SLAVE ADDRESS d7 MSB LSB d6 d5 d4 d3 MOST SIGNIFICANT DATA BYTE d0 MASTER ACK d7 LSB d6 d5 d4 d3 d2 d1 d0 STOP LEAST SIGNIFICANT DATA BYTE BYTE WRITE MSB START 1 MSB LSB 0 0 1 0 0 0 0 SLAVE ACK 0 SLAVE ADDRESS MSB LSB 0 0 p4 p3 POINTER BYTE p2 p1 p0 SLAVE ACK d7 LSB d6 d5 d4 d3 d2 d1 d0 SLAVE ACK STOP DATA BYTE Figure 4. Read/Write Protocols 15 MAX17135 I2C Interface Output Control The IC’s source-driver and gate-driver outputs (GVEE, NEG, POS, and GVDD) and VCOM amplifier output can be controlled by driving the IC’s EN and CEN pins, respectively. Alternatively, the EN and CEN pins can be left unconnected or connected to GND such that their corresponding functions can be controlled by toggling the EN and CEN bits in the enable register. All outputs are brought up with soft-start control to limit the inrush current. MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications I2C Address The IC is a slave-only device and responds to the 7-bit address 90h. The read and write commands can be distinguished by adding 1 more bit (R/W bit) to the end of the 7-bit slave address, with 1 indicating read, and 0 indicating write. A7 A6 A5 A4 A3 A2 A1 A0 1 0 0 1 0 0 0 R-/W I2C Registers The device contains 20 data registers along with an additional Pointer register. The Pointer register selects which of the other 19 data registers to be read from or written to. At power-up, the Pointer is set to read the External Temperature register at address 0x00. The Pointer register latches the last location to which it was set. P7 P6 P5 0 0 0 P4 P3 P2 P1 P0 Register Select P4–P0 Register Select P4–P0 (HEX) 16 REGISTER NO. OF BITS POR STATE 00 External Temperature register (read only) (power-up default) 16 N/A 01 Configuration register (read/write) 8 00h 04 Internal Temperature register (read only) 16 N/A 05 Status register (read only) 8 N/A 06 Product Revision register (read only) 8 00h 07 Product ID Register (read only) 8 4Dh 08 DVR register (R/W) 8 FFh 09 Enable register (R/W) 8 00h 0A Fault register (read only) 8 N/A 0B HVINP register (R/W) 8 0Ah 0C Programming Control register (write only) 8 N/A 0Fh Temperature Conversion Rate register 8 04h 10 t1 Timing register (R/W) 8 1Eh (factory default) 11 t2 Timing register (R/W) 8 3Ch (factory default) 12 t3Timing register (R/W) 8 5Ah (factory default) 13 t4 Timing register (R/W) 8 78h (factory default) 14 t5 Timing register (R/W) 8 1Eh (factory default) 15 t6 Timing register (R/W) 8 3Ch (factory default) 16 t7 Timing register (R/W) 8 5Ah (factory default) 17 t8 Timing register (R/W) 8 78h (factory default) Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Sign Bit 1 = Negative 0 = Positive +64NC +32NC +16NC +8NC +4NC +2NC +1NC +0.5NC X X X X X X X X = Don’t care. DIGITAL OUTPUT TEMPERATURE (NC) BINARY HEX +125 0111 1101 0XXX XXXX 7D0X +25 0001 1001 0XXX XXXX 190X +0.5 0000 0000 1XXX XXXX 008X 0 0000 0000 0XXX XXXX 000X -0.5 1111 1111 1XXX XXXX FF8X -25 1110 0111 0XXX XXXX E70X X = Don’t care. Configuration Register (01h) (R/W) After the IN and VDD voltages have risen above their respective undervoltage-lockout thresholds, the Shutdown bit (D0) is set to 0 and temperature conversions begin immediately. Temperature conversions are continually performed every 1s unless the temperature sensor is put into shutdown mode. Set D0 to 1 to put the temperature sensor in shutdown mode to reduce supply current. D0: SHUTDOWN: When set to 1, the temperature sensor is shut down. D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 0 0 0 Shutdown Status Register (05h), Read Only The Status register indicates whether the IC’s ADC is in the process of performing a temperature conversion and whether there are any fault conditions with the remote temperature-sensing diode. Any fault condition with the external temperature-sensing diode causes the external temperature register to return 7FC0h. D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 0 SHORT OPEN BUSY D0: BUSY: Is set to 1 when the ADC is in the process of performing a temperature conversion. D1: OPEN: Is set to 1 when any connections from DXN and DXP to the temperature-sensing diode are open. D2: SHORT: Is set to 1 when there is a short-circuit condition between DXP and DXN. 17 MAX17135 out in word format: an upper byte and a lower byte. Bits D15–D7 contain the temperature data, with the LSB representing +0.5NC and the MSB representing the sign bit. The last 7 bits of the lower byte, bits D6–D0, are don’t care. External and Internal Temperature Registers (00h and 04h), Read Only The temperature data format of the External Temperature register (00h) and the Internal Temperature register (04h) are both 9 bits, two’s complement, and are read MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications Product Revision Register (06h), Read Only This register contains the product revision 0x00h. D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 0 0 0 0 Enable Register (09h) R/W The output enable functions performed by the EN and CEN pins can also be performed through I2C commands by setting the function’s corresponding enable bit in the Enable register. Product Identification Register (07h), Read Only Maxim is indicated by 0x4Dh. D7 D6 D5 D4 D3 D2 D1 D0 0 1 0 0 1 1 0 1 DVR Register (08h) R/W The VCOM voltage can be set anywhere between -0.5V and -3.050V with 10mV per LSB by programming the DVR register with a corresponding value as shown in the table below. During power-up, once IN and VDD exceed their undervoltage-lockout thresholds, the DVR register is programmed with a value stored in the nonvolatile memory to set the VCOM voltage. The factory-default DVR value stored in the nonvolatile memory is 7F. See the Programming Control Register (0Ch), Write Only section for details regarding changing the preset DVR value. D7 D6 D5 D4 D3 D2 D1 D0 MSB Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 LSB 18 DVR REGISTER VCOM OUTPUT VOLTAGE (V) 00h -0.50 01h -0.51 … … 7Fh -1.77 … … FEh -3.04 FFh -3.05 D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 0 0 CEN EN Each function’s enable bit is ORed with the status of its corresponding enable pin to determine whether the function is to be performed. If I2C control over the EN and CEN functions is desired, leave the EN and CEN pins unconnected or connect them to GND such that when: • The EN bit is set to 1; the GVEE, NEG, POS, and GVDD power rails begin a power-up sequence. The sequence order and timing between the startup of each power rail is determined by the information stored in the t1–t4 Timing registers at the time the EN bit is set to 1. • The EN bit is set to 0; the GVEE, NEG, POS, and GVDD begin a power-down/discharge sequence based on the information stored in the Timing registers. The sequence order and timing between the power-down of each power rail is determined by the information stored in the t5–t8 Timing registers at the time the EN bit is set to 0. • The CEN bit is set to 1; the VCOM output is enabled. • The CEN bit is set to 0; the VCOM output is discharged to ground. During a fault condition, all bits in the Enable register are cleared (EN = CEN = 0). Driving the EN or CEN pins high or low has no effect on the EN or CEN settings in the Enable register. Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications The POK bit in the Fault register is not a fault indicator, but rather a status indicator that is asserted to 1 after FBNG, NEG, POS, and FBPG have all exceeded 80% of their regulation voltages and all soft-start periods have completed. The POK bit is set to 0 once the power-down sequence has been initiated by setting the EN bit to 0 or once a fault condition has occurred. The status of POK itself does not directly affect the status of EN or CEN bits. Note: The temperature sensor DXN/DXP short-circuit and open-circuit “faults” are not latching faults that cause the IC to shut down and do not set the CEN or EN bits’ status. D7 D6 D5 D4 D3 D2 D1 D0 POK OT HVINNSC HVINPSC FBNG HVINN HVINP FBPG FBPG = GVDD undervoltage fault the desired HVINP regulation voltage into the HVINP register through I2C (see the table below). Programming the HVINP register to set the HVINP regulation voltage gives the flexibility to change the HVINP regulation voltage between each power-up sequence of the GVEE, NEG, POS, and GVDD rails and removes external components. To set the HVINP regulation voltage through I2C, connect the FBP pin to GND. With FBP connected to GND, the HVINP register is automatically loaded with 0Ah and the HVINP regulation voltage is set to +15V after IN and VDD have exceeded their undervoltage-lockout thresholds. If another HVINP regulation voltage other than +15V is desired, write a new value to the HVINP register that corresponds to the desired HVINP regulation voltage after IN and VDD have exceeded their undervoltage-lockout thresholds, but before EN is asserted high. The new HVINP regulation voltage is maintained until a new value is written to the HVINP register or the VDD input power is cycled. After cycling VDD, the HVINP register is again reloaded with 0Ah such that it is necessary to rewrite the HVINP register to change the HVINP regulation voltage to another voltage other than VHVINP = 15V. D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 MSB Bit2 Bit1 LSB HVINP = HVINP undervoltage fault HVINN = HVINN undervoltage fault FBNG = GVEE undervoltage fault HVINPSC = HVINN short-circuit fault HVINNSC = HVINN short-circuit fault OT = Thermal shutdown POK = Power-OK HVINP Register (0Bh) R/W The POS regulation voltage is determined by the boost converter’s output regulation voltage (VHVINP). The HVINP regulation voltage is set by using a resistor-divider network or by programming the corresponding value of The HVINP register can be programmed to provide a POS regulation voltage from 00h (VPOS = 5V) to 0Ch (VPOS = 17V) adjustable in 1V steps. HVINP REGISTER HVINP OUTPUT VOLTAGE (V) 00h 5 01h 6 ... ... 0Ah 15 0Bh 16 0Ch 17 19 MAX17135 Fault Register (0Ah) Read Only During a fault condition, all outputs of the device are latched off, all bits in the Enable register are set to 0, and the corresponding bit of the fault condition is set in the Fault register (see the table below). After the fault condition is removed, the Fault register is cleared by cycling the VDD supply. MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications Conversion Rate Control Byte (0Fh) R/W The Conversion Rate register (0Fh) programs the time interval between conversions in the free-running autoconvert mode of the temperature sensors. This variablerate control reduces the supply current in portableequipment applications. The conversion rate control byte’s POR state is 04h. The control mechanism looks only at the 3 LSBs of this register, so the upper 5 bits are “don’t care” bits, which should be set to zero. The conversion rate tolerance is ±25% at any rate setting. DATA CONVERSION RATE (Hz) AVERAGE SUPPLY CURRENT OF TEMPSENSOR BLOCK (μA) 00h 0.0625 14 01h 0.125 18 02h 0.25 26 41 • POK is asserted high after FBNG, NEG, POS, and FBPG have all exceeded 80% of their regulation voltages and all the corresponding power rails’ soft-start periods have expired. • Once EN is driven low or the EN bit in the Enable register is set to 0 (while the EN is disconnected or is connected to GND), POK is asserted low and each power rail is discharged at a time depending on the values stored in the timing registers (t5–t8). Approximately 512ms after EN is driven low, HVINP and HVINN are powered down but not discharged. The power-up/power-down sequence and timing between the GVEE, NEG, POS, and GVDD power rails can be set by programming the t1–t8 registers with corresponding values according to the table below. D7 D6 D5 D4 D3 D2 D1 D0 128ms 64ms 32ms 16ms 8ms 4ms 2ms 1ms 03h 0.5 04h 1 72 05h 2 133 06h 4 255 07h 8 500 TIME (ms) 08h to FFh Depends on the 3 LSB VALUE STORED IN A TIMING REGISTER (t1–t8) Depends on the 3 LSB 00h 0 Valid A/D conversion results are available one total conversion time after the initiating conversion, whether the conversion is initiated through the Shutdown bit in the Configuration Register or initial power-up. Changing the conversion rate can also affect the delay until new results are available. t1–t8 Timing Registers (10h–17h) R/W Figure 5 shows the start-up and shutdown sequence of the power rails: • The HVINP power rail begins its soft-start sequence once EN is driven high or the EN bit in the Enable register is set to 1. • The HVINN power rail begins its soft-start sequence once the HVINP soft-start period has expired. • The GVEE, NEG, POS, and GVDD power rails start up t1–t4ms after the expiration of the HVINN soft-start period. 20 The binary value stored in a register directly corresponds to the time in ms. 01h 1 ... ... FEh 254 FFh 255 During power-up of the device, once IN and VDD exceed their undervoltage-lockout thresholds, the t1–t8 registers are loaded with values stored in the nonvolatile memory to preset the t1–t8 timing. The factory-default timing settings in the nonvolatile memory are: • t1 = t5 = 30ms • t2 = t6 = 60ms • t3 = t7 = 90ms • t4 = t8 = 120ms To change the preset t1–t8 timing, see the Programming Control Register (0Ch), Write Only section. Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications MAX17135 4 5 GVDD 2 POS HVINP POK EN 1 NEG HVINN 3 GVEE t1 t5 t6 t2 t7 t3 t8 t4 512ms Figure 5. Adjustable Power-Up and Power-Down Sequencing Programming Control Register (0Ch), Write Only The Programming Control register (PCR) allows the user to update the nonvolatile memory containing the values used to set the DVR and Timing registers after initial power-up of the IC (after VDD and IN both exceed their undervoltage-lockout thresholds). D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 0 0 Timing DVR To change the nonvolatile memory values that preset the VCOM voltage, set EN to high to bring up the power rails. After POK is asserted high, write the value corresponding to the desired VCOM voltage setting into the DVR register. After the DVR register has been updated, write 1 to D0 of the PCR to update the nonvolatile memory with the current value stored in the DVR register. The nonvolatile memory containing the power-up DVR setting can be changed up to 30 times. The I2C bus returns NACK if the DVR nonvolatile memory is attempted to be programmed more than 30 times. To change the nonvolatile memory values that preset the power-up and power-down timing between the power rails, set EN to high to bring up the power rails. After POK is asserted high, write to all t1–t8 registers with the values corresponding to the desired t1–t8 timing between power rails. The t1–t8 values cannot be stored to the nonvolatile memory independently and all eight Timing registers must be written to at least once before attempting to update the nonvolatile memory with any new values, even if not all values need to be changed from the current values stored in the nonvolatile memory. Once all the Timing registers have been written to at least once, write 1 to D1 of the PCR to update the nonvolatile memory with the current values stored in all t1–t8 Timing registers. The nonvolatile memory containing the powerup and power-down timing settings can be changed up to three times. The I2C bus returns NACK if the t1–t8 nonvolatile memory is attempted to be programmed more than three times. Note: VPOS needs to be greater than 7.3V in order to successfully program the nonvolatile memory. 21 MAX17135 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications PCB Layout and Grounding Careful PCB layout is important for proper operation. Use the following guidelines for good PCB layout: • Minimize the inner loop area created by the boost converter high-switching current connections. Place D1 and C3 close to the IC such that the traces connecting the LXP pin to the anode of D1, the cathode of D1 to C3, and C3 to the PGND pin are kept as short as possible to minimize the loop area contained within these connections. Make these connections with short, wide traces. • Minimize the inner loop area created by the buckboost converter high-switching current connections. Place C6, C7, and D2 close to the IC such that the traces connecting C6 to the INN pin, the LXN pin to the cathode of D2, the anode of D2 to C7, and C6 ground connection to C7 are kept as short as possible to minimize the loop area contained within these connections. Make these connections with short, wide traces. • Avoid using vias in the high-current paths. If vias are unavoidable, use many vias in parallel to reduce resistance and inductance. • Create a power ground island (PGND) consisting of the PGND pin, the input and output capacitor ground connections, the charge-pump capacitor ground connections, and the buck-boost inductor ground connection. Connect all these together with short, wide traces or a small ground plane. Maximizing the width of the power ground traces improves efficiency and reduces output-voltage ripple and noise spikes. Create an analog ground plane (GND) consisting of the GND pin, all the feedback-divider ground connections, the IN, VDD, and REF bypass capacitor ground connections, and the device’s exposed backside paddle. • Connect the GND and PGND islands by connecting the PGND pin directly to the exposed backside paddle. Make no other connections between these separate ground planes. 22 • Place the feedback-voltage-divider resistors as close as possible to their respective feedback pins. Keep the traces connecting the feedback resistors to their respective feedback pins as short as possible. Placing the resistors far away causes the feedback trace to become an antenna that can pick up switching noise. Care should be taken to avoid running any feedback trace near the LXP, LXN, DP, or DN switching nodes. • Place the IN, VDD, and REF bypass capacitors as close as possible to the IC. The ground connections of the IN, VDD, and REF bypass capacitors should be connected directly to the analog ground plane or directly to the GND pin with a wide trace. • Minimize the length and maximize the width of the traces between the output capacitors and the load for best transient responses. • Keep sensitive signals away from the LXP, LXN, DP, and DN switching nodes. Use DC traces as a shield if necessary. Refer to the MAX17135 evaluation kit for an example of proper board layout. Chip Information PROCESS: BiCMOS Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 32 TQFN-EP T3255N+1 21-0140 90-0015 Multi-Output DC-DC Power Supply with VCOM Amplifier and Temperature Sensor for E-Paper Applications REVISION NUMBER REVISION DATE DESCRIPTION PAGES CHANGED 0 7/11 Initial release — 1 12/11 Typical Operating Circuit values updated 12 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2011 Maxim Integrated Products 23 Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX17135 Revision History