SM8133B White LED Driver IC OVERVIEW The SM8133B is a charge pump type white LED driver. It can drive 1 to 6 backlight white LED connected in parallel and 1 flash white LED. The output voltage circuit has a 3.0V LDO (Low Dropout Regulator), making the device ideal for camera-equipped cellular phones. The charge pump switches between ×1 to ×1.5 boost mode in response to LED drive current requirements to extend battery life to the maximum. The boost switching occurs in response to the drive current of all the connected LED and thus supports variations in LED forward-bias voltage drop (VF). Each LED drive current is controlled by a 7-channel LED drive current control circuit. The 6 backlight channels can be subdivided into 2 groups, with each group having independent dimming and lighting control. The backlight grouping, backlight LED drive current and ON/OFF control, flash LED drive current and ON/OFF control, and LDO output ON/OFF control are all set by 3-wire serial interface data input. Also, the RESETB pin can be connected to the microcontroller supply for a system-wide shutdown function. FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Noise reduction due to charge pump boost circuit Automatic charge pump switching to conserve power Drives 1 to 6 backlight white LED (30mA/ch at maximum setting) Drives a flash white LED (150mA at maximum setting) Backlight and flash white LED brightness adjustment Group settings for 2-group backlight lighting control 3-wire serial input interface for all setting and control 3.0V output LDO circuit built-in Shutdown function by RESETB pin Soft start circuit built-in Thermal protection circuit built-in ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ APPLICATIONS ■ ■ ■ ■ Cellular phone Digital still camera PDA Portable games Input voltage range • No-load current (IOUT = 0mA): 2.7 to 4.6V • Load current (IOUT = 80mA): 3.0 to 4.6V • Load current (IOUT = 200mA): 3.3 to 4.6V Quiescent current • LDO only: 0.3mA (typ) • Not -switching (×1.0 mode): 0.5mA (typ) • Switching (×1.5 mode): 2.5mA (typ) Standby current: 0.01µA (typ) Operating frequency: 750kHz (typ) Backlight LED current: 30mA/ch (typ) Flash LED current: 150mA (typ) All LED total maximum current: 200mA (typ) Backlight LED current matching (ILED = 30mA) : ± 3% Flash LED current accuracy (ILED = 150mA) : ± 5% LDO (Low Dropout Regulator) output voltage : 3.0V ± 2% Packages: 20-pin QFN WL-CSP (under development) ORDERING INFORMATION Device Package SM8133BB 20-pin QFN SM8133BW WL-CSP NIPPON PRECISION CIRCUITS INC.—1 SM8133B PACKAGE DIMENSIONS (Unit: mm) QFN-20 4.20 ± 0.20 4.00 ± 0.10 20 4.20 ± 0.20 4.00 ± 0.10 1 0.50 1.00MAX + 0.03 0.02 − 0.02 0.05 0.22 ± 0.05 0.22 0.60 ± 0.10 0.05 M WL-CSP (under development) Top view Bottom view 0.48 ± 0.03 0.4 2.56 ± 0.03 0.68 ± 0.03 B D C B A 1 2 3 4 5 20 − φ0.2 ± 0.03 0.08 ± 0.03 S 0.09 ± 0.007 0.55 ± 0.02 2.56 ± 0.03 0.4 φ0.05 M S AB A 0.06 S NIPPON PRECISION CIRCUITS INC.—2 SM8133B PINOUT (Top view) WL-CSP (under development) SDA SCK RESETB VOUT LDOUT QFN-20 15 14 13 12 11 EN DIN7 DIN6 DIN5 GND 16 17 18 19 20 10 9 8 7 6 D C B A VIN C2P C2M C1M C1P 5 4 3 2 1 DIN4 DIN3 DIN2 DIN1 PGND 1 2 3 4 5 PIN DESCRIPTION Number Name I/O D1 DIN4 O LED drive current control output 4 (connect to ground when not used) 2 C1 DIN3 O LED drive current control output 3 (connect to ground when not used) 3 B1 DIN2 O LED drive current control output 2 (connect to ground when not used) 4 B2 DIN1 O LED drive current control output 1 (connect to ground when not used) 5 A2 PGND – Charge pump ground connection 6 A1 C1P – Charge pump capacitor connection 1P 7 A3 C1M – Charge pump capacitor connection 1M 8 B3 C2M – Charge pump capacitor connection 2M 9 B4 C2P – Charge pump capacitor connection 2P 10 A4 VIN – Voltage supply 11 A5 LDOUT O LDO output 12 B5 VOUT O LED drive voltage output 13 C5 RESETB I Reset signal input (internal reset when RESETB is LOW) 14 C4 SCK I Serial data clock input 15 D5 SDA I Serial data input 16 D4 EN I Serial interface enable input 17 C3 DIN7 O LED drive current control output 7 (connect to ground when not used) 18 D3 DIN6 O LED drive current control output 6 (connect to ground when not used) 19 D2 DIN5 O LED drive current control output 5 (connect to ground when not used) 20 C2 GND – Ground QFN-20 WL-CSP 1 Description NIPPON PRECISION CIRCUITS INC.—3 SM8133B BLOCK DIAGRAM C1M C1P C2M C2P VIN Charge pump 1/ 1.5 VOUT Mode control & Output voltage control & Protection DIN1 DIN2 Current control & Under current detector Thermal shut down DIN3 DIN4 DIN5 RESETB DIN6 SCK Control logic DIN7 SDA EN LDO 3V & Protection GND LDOUT PGND NIPPON PRECISION CIRCUITS INC.—4 SM8133B SPECIFICATIONS Absolute Maximum Ratings GND = PGND = 0V Note. The device may suffer breakdown if any one of these parameter ratings is exceeded. Parameter Symbol Rating Unit VIN −0.3 to 5.5 V VEN, VSEL –0.3 to VIN + 0.3 V VDIN1 to 7 –0.3 to VIN + 0.3 V VOUT 5.5 V VOUT output current IOUT 500 mA LDO output current ILDO 200 mA PD 1429 (Ta = 25°C)*1 mW TJMAX +125 °C Tstg −55 to +125 °C Supply voltage range Input voltage range Output voltage range Power dissipation Junction temperature Storage temperature range *1. When mounted on a 34 × 40 × 1.6mm glass epoxy board, the power dissipation is related to the operating temperature by the following equation. ■ Maximum junction temperature: TMAX = 125°C Operating temperature: Ta [°C] Thermal resistance: θJ = 70°C/W PD = 1600 1429 Power dissipation [mW] ■ ■ (TMAX − Ta) θJ 1143 1200 857 800 571 400 0 25 35 45 55 65 75 85 Operating temperature [°C] Recommended Operating Conditions GND = PGND = 0V Rating Parameter Supply voltage range Input voltage range Ambient temperature range Pin Symbol Conditions Unit min typ max VIN1 ×1.0 mode, IOUT = 0mA 2.7 3.6 4.6 V VIN2 ×1.5 mode, IOUT = 80mA 3.0 3.6 4.6 V VIN3 ×1.5 mode, IOUT = 200mA 3.3 3.6 4.6 V EN, SCK, SDA, RESETB VES Each logic-level pin 0 − VIN V − Ta −30 − +85 °C VIN NIPPON PRECISION CIRCUITS INC.—5 SM8133B Electrical Characteristics DC Characteristics GND = PGND = 0V, VIN = 3.6V, Ta = 25°C unless otherwise noted. Rating Parameter Standby current Quiescent current Pin VIN VIN Symbol Condition Unit min typ max ISTB Standby mode – 0.01 1.00 µA IDD1 LDO-only operating, no load – 0.3 0.7 mA IDD2 ×1.0 mode, no load – 0.5 1.0 mA IDD3 ×1.5 mode, no load – 2.5 4.0 mA Maximum output voltage VOUT VOUT ×1.5 mode VOUT maximum voltage 4.8 5.0 5.2 V Maximum output current VOUT IOUT ×1.5 mode 200 – – mA Operating frequency C1M fOSC ×1.5 mode switching frequency 650 750 850 kHz EN TPOR Time from when power is applied until internal circuit reset – 0.02 0.10 ms Soft start time DIN1 to 7 TSS Time between EN signal falling edge and LED turning ON – 1.3 3.0 ms LED drive pin leakage current DIN1 to 7 ILEAK1 to 7 Standby mode, VDIN1 to 7 = 5.0V – 0.01 1.00 µA LED drive current matching DIN1 to 6 ∆ILED ×1.0 mode, matching between channels with ILED1 to 6 maximum setting –3.0 – +3.0 % LED maximum drive current 1 DIN1 to 6 ILED1 to 6 ×1.0 mode, ILED1 to 6 maximum setting 27.0 30.0 33.0 mA LED drive pin voltage 1 DIN1 to 6 VDIN1 to 6 ILED1 to 6 maximum setting 80 120 150 mV LED maximum drive current 2 DIN7 ILED7 ×1.5 mode, ILED7 maximum setting 142.5 150.0 157.5 mA LED drive pin voltage 2 DIN7 VDIN7 IDIN7 maximum setting 225 300 375 mV LDO output voltage LDOUT VLDO VIN = 3.6V, ILDO = 100mA 2.94 3.00 3.06 V LDO maximum output current LDOUT ILDO VIN = 3.0V, VLDO = 2.85V 100 – – mA LDO input stability LDOUT ∆VOUT1 3.3V ≤ VIN ≤ 4.6V, ILDO = 30mA – – 1.0 %/V LDO load stability LDOUT ∆VOUT2 VIN = 3.6V, 10µA ≤ ILDO ≤ 80mA – – 100 mV LDO overcurrent protection circuit operating current LDOUT IOS VIN = 3.6V 120 230 360 mA Thermal protection circuit operating temperature*1 – TSD Not in test mode – 180 – °C Thermal protection circuit hysteresis*1 – TSDHYS Not in test mode – 20 – °C Logic-level input voltage EN, SCK, SDA, RESETB Internal circuit power-ON reset time*1 Logic-level input current EN, SCK, SDA, RESETB VIH HIGH-level input voltage range 1.8 – – V VIL LOW-level input voltage range – – 0.6 V Hysteresis voltage width – 0.3 0.5 V IIL EN = SCK = SDA = RESETB = VIN – – 1.0 µA IIH EN = SCK = SDA = RESETB = GND –1.0 – – µA VIHYS *1. Design guaranteed value NIPPON PRECISION CIRCUITS INC.—6 SM8133B AC Characteristics GND = 0V, VIN = 3.6V, Ta = 25°C unless otherwise noted. Rating Parameter Symbol Condition Unit min typ max SCK clock cycle tSCK 2000 – DC ns SCK HIGH-level pulse width tWH 800 – – ns SCK LOW-level pulse width tWL 800 – – ns EN setup time tCS 1000 – – ns EN hold time tCH 800 – – ns EN recovery time tCR 1000 – – ns Write data setup time tDS 600 – – ns Write data hold time tDH 600 – – ns EN tCS tCR tWL SCK tWH tCH tSCK tDH tDS SDA Data input timing diagram NIPPON PRECISION CIRCUITS INC.—7 SM8133B VOUT EFFICIENCY 100 VOUT power efficiency [%] 90 80 VF = 3.2V VF = 3.4V VF = 3.6V 70 VF = 3.8V 60 50 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.4 4.6 VIN [V] Efficiency of PIN vs. POUT Backlight LED × 6pcs, ILED1 to 6 = 20mA, Flash LED × 1pc, ILED7 = 0mA, IOUT = 120mA, ILDO = 0mA 100 VOUT power efficiency [%] 90 80 VF = 3.2V VF = 3.4V VF = 3.6V VF = 3.8V 70 60 50 3.2 3.4 3.6 3.8 4.0 4.2 VIN [V] Efficiency of PIN vs. POUT Backlight LED × 3pcs, ILED1 to 6 = 15mA, Flash LED × 1pc, ILED7 = 0mA, IOUT = 45mA, ILDO = 0mA NIPPON PRECISION CIRCUITS INC.—8 SM8133B 100 VOUT power efficiency [%] 90 80 VF = 3.2V VF = 3.4V 70 VF = 3.6V VF = 3.8V 60 50 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 VIN [V] Efficiency of PIN vs. POUT Backlight LED × 6pcs, ILED1 to 6 = 20mA, Flash LED × 1pc, ILED7 = 80mA, IOUT = 200mA, ILDO = 0mA 100 VOUT power efficiency [%] 90 80 VF = 3.2V VF = 3.4V VF = 3.6V 70 VF = 3.8V 60 50 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 VIN [V] Efficiency of PIN vs. POUT Backlight LED × 3pcs, ILED1 to 6 = 15mA, Flash LED × 1pc, ILED7 = 150mA, IOUT = 195mA, ILDO = 0mA NIPPON PRECISION CIRCUITS INC.—9 SM8133B 100 VOUT power efficiency [%] 90 80 VF = 3.2V 70 VF = 3.4V VF = 3.6V VF = 3.8V 60 50 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 VIN [V] Efficiency of PIN vs. POUT Backlight LED × 6pcs, ILED1 to 6 = 20mA, Flash LED × 1pc, ILED7 = 80mA, IOUT = 200mA, ILDO = 100mA 100 VOUT power efficiency [%] 90 80 VF = 3.2V 70 VF = 3.4V VF = 3.6V VF = 3.8V 60 50 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 VIN [V] Efficiency of PIN vs. POUT Backlight LED × 3pcs, ILED1 to 6 = 15mA, Flash LED × 1pc, ILED7 = 150mA, IOUT = 195mA, ILDO = 100mA NIPPON PRECISION CIRCUITS INC.—10 SM8133B FUNCTIONAL DESCRIPTION Serial Interface The SM8133B uses a 3-wire serial interface to control each setting. Input data on SDA is input MSB first in an 8 clock pulse cycle structure, with the first 4 cycles of data setting the mode and the next 4 the corresponding mode data. Data bits on SDA are read as received data on the rising edges of the SCK clock after EN goes HIGH. Only the leading 8 bits on SDA are read after EN goes HIGH and all subsequent input data bits are ignored, but the received data is reflected in SM8133B operation with timing almost simultaneous with the EN falling edge. Conversely, if less than 8 bits are input on SDA, the data is ignored to prevent incorrect operation. All registers are write-only, and their status cannot be read. After power is applied, an internal power-ON reset circuit initializes all registers to logic level LOW in standby mode. However, the possibility exists that there may be insufficient reset time, depending on the VIN input voltage rise time and fall time, so reset mode (0H or EH) should be expressly invoked after power is applied. There is no restriction in the input sequence when setting parameters. However, since the parameters are set in the same order as the data input sequence and the time taken from LED ON/OFF data input to LED dimming data input can exceed the soft start time, it is highly advisable to enter the LED dimming data first. The charge pump circuit, that supplies the LED drive voltage, starts whenever any parameter in address 5H (LED ON register) is set to 1, with the LED drive voltage output on VOUT. Conversely, when all parameters in address 5H are set to 0, all other parameter data settings input after reset are retained in standby mode. The serial interface pins EN, SDA, CSK, and RESETB are CMOS inputs, thus the input voltage on VIN must be a logic-level voltage and should not be left open circuit (floating). Control Data Mode selection data Setting data M1 M2 M3 M4 D1 D2 D3 D4 MSB Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 LSB EN SCK SDA M1 M2 M3 M4 D1 D2 D3 D4 Control data input sequence ■ Mode selection Mode data 0H 1H 2H 3H 4H Mode Reset Grouping A group dimming B group dimming DIN7 dimming M1-M2-M3-M4 L-L-L-L L-L-L-H L-L-H-L L-L-H-H L-H-L-L Mode data 5H 6H EH FH Other Mode LED ON System settings Reset Serial input test NPC test M1-M2-M3-M4 L-H-L-H L-H-H-L H-H-H-L H-H-H-H − NIPPON PRECISION CIRCUITS INC.—11 SM8133B Mode data “0H”: Reset register Mode data “EH”: Reset register Setting data D1 D2 D3 High All system data reset Low System standby D4 Reset mode is selected if EN goes LOW 4 clock cycles after 0H or EH mode select data is input, regardless of when power is applied or the parameter set data bits. When reset mode is selected, all data input previously is reset, thus grouping, dimming, and control data must be reentered. Mode data “1H”: Grouping register Setting data D1 D2 D3 D4 High LED3 = B group LED4 = B group LED5 = B group LED6 = B group Low LED3 = A group LED4 = A group LED5 = A group LED6 = A group LED1 and LED2 are always assigned to A group. When a setting data bit is LOW, A group is selected. When HIGH, B group is selected. Mode data “2H”: A group dimming register Mode data “3H”: B group dimming register Mode data “4H”: DIN7 dimming register Setting data D1 D2 D3 D4 Selected dimming value 0H Low Low Low Low 0/15 1H Low Low Low High 1/15 2H Low Low High Low 2/15 3H Low Low High High 3/15 4H Low High Low Low 4/15 5H Low High Low High 5/15 6H Low High High Low 6/15 7H Low High High High 7/15 8H High Low Low Low 8/15 9H High Low Low High 9/15 AH High Low High Low 10/15 BH High Low High High 11/15 CH High High Low Low 12/15 DH High High Low High 13/15 EH High High High Low 14/15 FH High High High High 15/15 D1 to D4 setting data bits control the each group LED current in 15 steps. See “LED drive current”. NIPPON PRECISION CIRCUITS INC.—12 SM8133B Mode data “5H”: LED ON register Setting data D1 D2 D3 D4 High A group ON B group ON DIN7 ON LDO ON Low A group OFF B group OFF DIN7 OFF LDO OFF This register controls the A group, B group, DIN7, and LDO ON/OFF state. Each state is ON when the corresponding bit is HIGH, and OFF when LOW. Each circuit starts when the corresponding bit in address 5H is set HIGH, transferring from standby mode. It is recommended that these 4 data settings be held LOW when possible to control current consumption. Mode data “6H”: System register Setting data D1 D2 D3 D4 High A group maximum current = 15mA B group maximum current = 15mA DIN7 maximum current = 75mA − Low A group maximum current = 30mA B group maximum current = 30mA DIN7 maximum current = 150mA − Note. Target values only. Current rating accuracy is not guaranteed. This register sets the maximum current drive for each group. For A and B group, LOW sets 30mA as the maximum, HIGH sets 15mA. For DIN7, LOW sets 150mA, HIGH sets 75mA as the maximum. LED drive current (Hexadecimal) A group Dimming register value B group DIN7 A group max. current = 0 A group max. current = 1 B group max. current = 0 B group max. current = 1 DIN7 max. current = 0 DIN7 max. current = 1 Unit 0H 0 0 0 0 0 0 mA 1H 2 1 2 1 10 5 mA 2H 4 2 4 2 20 10 mA 3H 6 3 6 3 30 15 mA 4H 8 4 8 4 40 20 mA 5H 10 5 10 5 50 25 mA 6H 12 6 12 6 60 30 mA 7H 14 7 14 7 70 35 mA 8H 16 8 16 8 80 40 mA 9H 18 9 18 9 90 45 mA AH 20 10 20 10 100 50 mA BH 22 11 22 11 110 55 mA CH 24 12 24 12 120 60 mA DH 26 13 26 13 130 65 mA EH 28 14 28 14 140 70 mA FH 30 15 30 15 150 75 mA Note. “H”: Hexadecimal Note. Target values only. Current rating accuracy is not guaranteed. NIPPON PRECISION CIRCUITS INC.—13 SM8133B LDO (Low Dropout Voltage Regulator) Operation is controlled using the LDO register (LSB in address “5H”). When the LDO register is set to 1, a regulated stable voltage is output from LDOUT. If the overcurrent protection circuit connected to LDOUT detects a continuous overcurrent condition for approximately 200µs, the LDO output stops and then restarts after a delay of approximately 1.4 seconds. At this point, if an overcurrent condition is detected again, the LDO output stops. If the overcurrent condition is detected a total of 12 successive times (approximately 16.8 seconds), the LDO load is deemed to be abnormal and the LDO output stops completely. The abnormal load condition is released only by selecting reset mode operation. THERMAL SHUTDOWN CIRCUIT (Overheating Protection) The thermal shutdown circuit operates whenever the IC temperature exceeds approximately 180°C for whatever reason. VOUT output recommences when the IC temperature falls below approximately 160°C. RESETB INPUT (Internal Circuit Reset Signal) If the microcontroller, which drives the serial data inputs, stops, the SM8133B logic-level signal inputs are left floating and the SM8133B will most likely not transfer to standby mode normally. However, the RESETB pin can be connected to the microcontroller supply pin, so that the SM8133B is reset automatically whenever the voltage on RESETB drops. A pull-down resistor should be connected between RESETB and GND to avoid a floating RESETB input with voltage applied to the VIN pin. NIPPON PRECISION CIRCUITS INC.—14 SM8133B STARTUP SEQUENCE After power is applied to the SM8133B or when a reset input occurs (active-LOW input on RESETB or reset register mode setting), the internal power-ON reset circuit initializes all registers to their default value of 0. Consequently, all required data for LED drive operation must be input using the serial interface. The registers can be addressed in arbitrary sequence. Note that the registers are set in the same sequence as they are addressed. Example 1. Set LED1 to LED6 to 30mA drive without group setting Set EN HIGH, input “2FH” using the serial interface, set EN LOW (A group current setting 30mA), set EN HIGH, input “58H”, set EN LOW (A group ON), LED1 to LED6 turn ON after the soft start ends. Set A group current: 30mA (2FH) A group ON (58H) EN 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 SCK SDA Approx. 30mA Soft start time ILED1 to 6 Example 1 input waveform Example 2. Set LED1 to LED4 to A group, LED5 and LED6 to B group, and individual group brightness Input “13H” using the serial interface (group setting), input “25H” (A group current setting 10mA), input “3AH” (B group current setting 20mA), input “5CH” (A and B groups ON) on successive EN cycles. LED1 to LED6 turn ON after the soft start ends. Set grouping (13H) LED1 to LED4 A group LED5 to LED6 B group Set A group current: 10mA (25H) Set B group current: 20mA (3AH) A group, B group ON (5CH) EN 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 SCK SDA Soft start time Approx. 10mA ILED1 to 4 Approx. 20mA ILED5 to 6 Example 2 input waveform NIPPON PRECISION CIRCUITS INC.—15 SM8133B Example 3. Set LED1 to LED6 to 30mA drive, temporarily turn OFF, turn ON again, and reset using RESETB input without group setting Input “2FH”(A group current setting 30mA) and “58H” (A group ON) from the serial interface. LED1 to LED6 turn ON after the soft start ends. While the LEDs are ON, input “50H” (A group OFF) to turn the LEDs OFF and transfer the SM8133B to standby mode. The internal register setting “2FH” (A group current setting 30mA) data is retained during standby mode, so you need to input “58H” (A group ON) only to turn the LEDs ON again. At this point, the charge pump soft start circuit operates again, taking a soft start time of approximately 1.3ms from when the data is input to when the LEDs turn ON. If RESETB is connected to the microcontroller power supply and the supply goes LOW, the SM8133B is reset, the LEDs turn OFF, and operation transfers to standby mode. RESETB Reset Reset mode LED mode LED ON mode Set A Group current : 30mA (2FH) Reset mode A group ON (58H) A group OFF (50H) A group ON (58H) EN 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 SCK SDA ILED1 to 6 Soft start time Approx. 30mA Soft start time Approx. 30mA Example 3 input waveform NIPPON PRECISION CIRCUITS INC.—16 SM8133B TYPICAL APPLICATION CIRCUIT If the RESETB input is connected to the microcontroller power supply, the SM8133B is reset when microcontroller power supply stops, and operation transfers to standby mode. In circuits where the SM8133B logic-level inputs would become open circuit (floating) when the microcontroller supply stops, pull-down resistors should be connected to each logic-level signal input. C1 1.0µF C1M C1P VIN 2.7 to 4.6V Battery C4 2.2µF C2 1.0µF C2M C2P VOUT Charge pump 1/ 1.5 C3 2.2µF Back Light Max 30mA 6ch DIN1 Mode control & Output voltage control & Protection LDO for microcontroller power source DIN2 DIN3 Current control & Under current detector Thermal shut down DIN4 DIN5 RESETB DIN6 Pull down VDD SCK Microcontroller SDA Control logic DIN7 EN Pull down Flash Max 150mA LDO 3V & Protection GND LDOUT 3V ± 2% (VIN ≥ 3.2V) Max 100mA C5 1.0µF PGND Note. If the driving LEDs are less than 7 pcs, the unused DIN pins should be connected to GND. NIPPON PRECISION CIRCUITS INC.—17 SM8133B PERIPHERAL PARTS About the External Capacitors The best capacitors for use with the SM8133B are multi-layer ceramic capacitors. When selecting a multi-layer ceramic capacitor, only X5R and X7R dielectric types are strongly recommended, since the loss of capacitance in various conditions is less than other types such as Z5U and Y5V. The much loss of capacitance in various conditions may cause the output voltage unstable. Table. The EIA three digit "TC" code Lower temperature limit High temperature limit Maximum allowable capacitance change from + 25°C (0V DC) X = −55°C 5 = +85°C F = ± 7.5% Y = −30°C 6 = +105°C P = ± 10% Z = +10°C 7 = +125°C R = ± 15% 8 = +150°C S = ± 22% T = +22%/−33% U = +22%/−56% V = +22%/−82% For example : X5R About the Input Capacitor "C4" The parts layout of PCB may merely cause the “VOUT” output voltage unstable. In this case, increasing the “C4” input capacitance value or adding another capacitor on the VIN input line is effective to solve the unstable output voltage. QFN-20 Package Package corner metals are not IC I/O pins. Don’t connect any lines to these corner metals. Bottom view NIPPON PRECISION CIRCUITS INC.—18 SM8133B FOOTPRINT PATTERN The optimum footprint varies depending on the board material, soldering paste, soldering method, and equipment accuracy, all of which need to be considered to meet design specifications. (Unit: mm) HE HD e b3 l1 l2 QFN-20 4.2 4.2 0.5 0.30 ± 0.05 0.20 ± 0.05 0.70 ± 0.05 HE /2 Package b3 HE e b3 l1 e l2 l2 l1 HD /2 HD NIPPON PRECISION CIRCUITS INC.—19 SM8133B Please pay your attention to the following points at time of using the products shown in this document. The products shown in this document (hereinafter “Products”) are not intended to be used for the apparatus that exerts harmful influence on human lives due to the defects, failure or malfunction of the Products. Customers are requested to obtain prior written agreement for such use from NIPPON PRECISION CIRCUITS INC. (hereinafter “NPC”). Customers shall be solely responsible for, and indemnify and hold NPC free and harmless from, any and all claims, damages, losses, expenses or lawsuits, due to such use without such agreement. NPC reserves the right to change the specifications of the Products in order to improve the characteristic or reliability thereof. NPC makes no claim or warranty that the contents described in this document dose not infringe any intellectual property right or other similar right owned by third parties. Therefore, NPC shall not be responsible for such problems, even if the use is in accordance with the descriptions provided in this document. Any descriptions including applications, circuits, and the parameters of the Products in this document are for reference to use the Products, and shall not be guaranteed free from defect, inapplicability to the design for the mass-production products without further testing or modification. Customers are requested not to export or re-export, directly or indirectly, the Products to any country or any entity not in compliance with or in violation of the national export administration laws, treaties, orders and regulations. Customers are requested appropriately take steps to obtain required permissions or approvals from appropriate government agencies. NIPPON PRECISION CIRCUITS INC. 15-6, Nihombashi-kabutocho, Chuo-ku, Tokyo 103-0026, Japan Telephone: +81-3-6667-6601 Facsimile: +81-3-6667-6611 http://www.npc.co.jp/ Email: [email protected] NC0503AE 2005.06 NIPPON PRECISION CIRCUITS INC.—20