AS3685B TAOS | Alldatasheet
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Technical content
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AS3685A/AS3685B austriamicro systems Datasheet www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 1 - 24
1 General Description
The AS3685 is low noise high efficiency capacitive charge pump with 1:1, 1:1.5 and 1:2 operating modes in a small 3x3mm DFN10 or a tiny 2x1.5mm WL-CSP (Wafer Level Chip Scale Package) package. It can drive one flash led at up to 1000mA current. It supports flas h/torch and indicator mode for the flash led. Additionally the AS3685 limits the flash time automatically to protect the flash LED.
2 Key Features
High Efficiency capactive charge pump with 1:1, 1:1.5 and 1:2 modes − 1:2 Mode can be disabled (different device versions available) Up to 1000mA Led Current Automatic Charge Pump Mode switching (Up) LED cathode disconnect in Shutdown Overtemperature Protection Automatic 800ms Flash Timeout to protect the flash LED Two Device Variants: − AS3685A: Direct control to select three currents − AS3685B: Single Pin Interface or Two Pin Interface with Strobe Input; 17 different currents can be selected Package − DFN10 3x3mm (10 pins + exposed pad) − WL-CSP (Wafer Level Chip Scale Package) 3x4 balls 0.5mm pitch (2x1.5mm)
3 Applications
Flash / Torch for Mobile Phones, Digital Cameras and PDA
4 Application Diagram
Figure 1 – Application Diagram of AS3685A/AS3685B C1+ C1- C2+ C2- CFLY1 1.0 FC FLY2 1.0 F VCP ILED AS3685A AS3685B ISET VBAT EN1 EN2 CBAT 2.2 F CVCP 2.2 F VBAT VSS DLED RISET RTXMASK AS3685A/AS3685B Ultra Small High Efficiency 1000mA Charge Pump for White LED Flash Datasheet ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 2 - 24 Table of Contents ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 3 - 24
5 Characteristics
5.1 Absolute Maximum Ratings
Stresses beyond those listed in Table 1 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 Section 5 Electrical Characteristics is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Table 1 – Absolute Maximum Ratings Symbol Parameter Min Max Unit Note VBATMAX Maximum Supply Voltage -0.3 7.0 V IIN Input Pin Current without causing latchup -25 +25 mA At 25ºC, Norm: Jedec 17 TSTRG Storage Temperature Range -55 125 °C Humidity 5 85 % Non condensing VESD Electrostatic Discharge -1000 1000 V Norm: MIL 883 E Method 3015
1.14 W DFN10 3x3mm, TA = 70°C 1
PT Total Continuous Power Dissipation 1.02 W WL-CSP 2x1.5mm, TA = 70°C 1 16.3 mW/ °C DFN10 3x3mm PDERATE PT Derating Factor 2 14.7 mW/ °C WL-CSP 2x1.5mm TJUNC Junction Temperature 150 °C TBODY Body Temperature during Soldering 260 °C according to IPC/JEDEC J- STD-020C Notes: 1. Depending on actual PCB layout and PCB used; for peak power dissipation during flashing see document ‘AS3685 Thermal Measurements’ For 1A flash current see application notes ‘AN3685_1Aflash’ and ‘AN3685_1Aflash_thermal_1v0’. 2. The PT derating factor changes the total conti nuous power dissipation, if the ambient temperature is different to 70°C. Therefore for e.g. 85°C calculate PT 85°C = PT – PDERATE * (85°C – 70 °C)
5.2 Operating Conditions
Table 2 – Operating Conditions Symbol Parameter Min Typ Max Unit Note VBAT Battery Supply Voltage 3.0 3.6 5.5 V Supply voltage range VBATFUNC Battery Supply Voltage, Functionally working 2.6 V AS3685 functionally working, but not all parameters fulfilled
0.4 A Depending on load current
and charge pump mode IBAT Operating Current
2.0 A Limited lifetime, max 20,000s
TAMB Ambient Temperature -30 25 85 °C IOFF Off mode current 1.0 4.0 μA EN1 = 0, EN2 = 0; VBAT<=4.2V ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 4 - 24 Table 2 – Operating Conditions Symbol Parameter Min Typ Max Unit Note 0.85 mA 1:1 Mode 6.6 mA 1:1.5 Mode IOPERATING Power Consumption without load 8.1 mA 1:2 Mode
5.3 Electrical Characteristics
Table 3 – Charge Pump Characteristics Symbol Parameter Min Typ Max Unit Note V(VCP) Output voltage without load – do not short to VSS VBAT * CP- mode V CP-mode is 1, 1.5 or 2 (automatically selected) VCPOUT Output limitation 5.4 5.6 internally limited 0.28 0.53 Ω 1:1 Mode VBAT = 3.6V, ICPOUT = 200mA 1.37 2.00 Ω 1:1.5 Mode VBAT = 3.3V, ICPOUT = 500mA, TJUNCTION<=85°C RCP Charge Pump effective Resistance 1.95 2.44 Ω 1:2 Mode VBAT = 3.0V, ICPOUT=700mA, TJUNCTION<=85°C Eta Efficiency 75 93 % Vin=3.0V-4.5V, Iout=100mA (Charge Pump alone) VRIPPLE Output ripple voltage 100 mVpp Vin=3.0-4.5V, Iout=350mA, fclk Operating Frequency -20% 1.0 +20% MHz tUP_DEB_LONG Initial Mode Switching Debounce Time 256 μs Mode switching up-debounce time after enabling of the charge pump or after mode switching between 1:1 to 1:1.5 tUP_DEB Mode Switching Debounce Time 16 μs Mode switching up-debounce time in normal operation Table 4 – Current Source (Sink) Characteristics Symbol Parameter Min Typ Max Unit Note ILED Output Current Range 700 1000 mA 700mA: RISET = 14.2kΩ 1000mA: RISET = 10kΩ IACCURACY Current Setting Accuracy -10% 500 +10% mA Measured with RISET = 19.9kΩ and maximum flash current VISET Current Generator Set Point Voltage (pin ISET) 1.3 V IISET Current Generator operating range 10.0 130 μA IISET = VISET / RISET if the resulting bias current is higher than 200μA (typ.), the current source is disabled IFLASH2ISET Flash Current to Bias Current Ratio 7650 A/A AS3685A, EN1=1, EN2=1 or AS3685B at full flash current (700mA with RISET = 14.2kΩ) ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 5 - 24 Table 4 – Current Source (Sink) Characteristics Symbol Parameter Min Typ Max Unit Note ITORCH2ISET Torch Current to Bias Current Ratio 1639 A/A AS3685A, EN1=0, EN2=1 (150mA with RISET = 14.2kΩ) 400 mV AS3685A, EN1=1, EN2=1 or AS3685B with ILED>350mA (with RISET = 14.2kΩ) VSWITCH Mode Switching Threshold on V(ILED) between 1:1 -> 1:1.5 and 1:1.5 -> 1:2 150 200 250 mV All lower currents Table 5 –Digital Interface characteristics Symbol Parameter Min Typ Max Unit Note VIH High Level Input voltage 1.5 VBAT V VIL Low Level Input voltage 0.0 0.5 V ILEAKAGE Input pin leakage current -10 10 μA tPULSEWIDTH Pulsewidth for signals on EN1 and EN2 (high or low pulses) 1.0 unlimited μs For Pins EN1 and EN2 Do not leave EN1 and EN2 floating; (47kΩ pulldowns can be used) Table 6 – Protection Functions Symbol Parameter Min Typ Max Unit Note TOVTEMP Overtemperature protection 140 °C TOVTEMPHYST Overtemperature protection Hysteresis 5 °C If the junction temperature exceeds TOVTEMP, the current sink will be disabled and the charge pump switched back into 1:1 mode until the temperature drops below TOVTEMP - TOVTEMPHYST tFLASHTIMEOUT Flash Timeout Time -20% 800 +20% ms AS3685A, EN1=1, EN2=1 or AS3685B flash modes ams AG Technical content still valid
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6 Typical Operation Characteristics
Figure 2 – Efficiency vs. Battery Voltage (with Lumiled PWF1) 100 VBAT [V] Efficiency of Charge Pump [%] ILED=700m ILED=600m ILED=500m ILED=400m ILED=300m ILED=200m ILED=100mILED=50m Figure 3 – Battery Current vs. Battery Voltage (with Lumiled PWF1) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 V BAT [V] IBAT [A] ILED=700m ILED=600m ILED=500m ILED=400m ILED=300m ILED=200m ILED=100mILED=50m Figure 4 – LED current I(ILED) vs. Battery Voltage (with Lumiled PWF1) 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 V BAT [V] ILED [A] ILED=700m ILED=600m ILED=500m ILED=400m ILED=300m ILED=200m ILED=100m ILED=50m Figure 5 – Linearty of Current Sink 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 V ILED [V] ILED [A] ILED=700m ILED=600m ILED=500m ILED=400m ILED=300m ILED=200m ILED=100m ILED=50m Figure 6 –I(ILED) vs. R(ISET) (Flash and Torch Mode of AS3685A) 200 400 600 800 1000 1200 0k 20k 40k 60k 80k 100k 120k 140k R ISET [Ohm] ILED [mA] Flash Mode Torch Mode Figure 7 – Startup of AS3685A -- ILED Current ILED 500mA/div 100µs/div VBAT=3.3V, ILED=700mA ams AG Technical content still valid
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7 Detailed Functional Description
Figure 12 – Internal Circuit Diagram of AS3685A/AS3685B
7.1 Low Noise Charge Pump
The AS3685 charge pump uses two external flying capacitors to generate output voltages higher than the battery voltage. The charge pump can operate in three different modes: 1:1 Bypass Mode or Off Mode − Battery input and output are connected by a low-impedance switch − Battery current = output current 1:1.5 Mode − The output voltage is 1.5 times t he battery voltage (without load) − Battery current = 1.5 times output current 1:2 Mode − The output voltage is 2 times the battery voltage (without load) − Battery current = 2 times output current The flying capacitors are switched at the fixed frequency fclk.
7.1.1 Mode Switching
The AS3685 monitors the voltage at the current sink V(ILED) and if this voltage falls below VSWITCH, for a time longer than the debounce time, the charge pump automatically switches into a higher mode. The debounce time is set to tUP_DEB_LONG at enabling of the charge pump or immediately after a 1:1 to 1:1.5 mode change. Afterwards the debounce time is reduced to tUP_DEB. (This allows the LED current to settle properly on startup or after a mode change) The charge pump enters always 1:1 mode in off mode or in case of overtemperature. It is possible to avoid the 1:2 mode (factory programmable) to limit the battery current to 1.5 times the output (=LED) current. C1+ C1- C2+ C2- VCP ILED ISET VBAT EN1 EN2 VBAT EN1 EN2 TXMask Low Noise Charge Pump Digital Control 1.3V Vswitch mode 5.3V soft_limit AS3685 Different Control Logic for AS3685A and AS3685B 1MHz clk Overtemp Detect VSS ams AG Technical content still valid
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7.1.2 Soft Start
The soft start mechanism reduces the inrush current. Battery current is smoothed when switching the charge pump on and also at each switching condition. This precaution reduces electromagnetic radiation significantly.
7.2 Current Source (Sink)
The AS3685 operates in three different modes: Indicator Mode: A small (average) current is used to obtain an indication function with the flash LED (e.g. indication for camera operation) Torch Mode: A moderate current of e. g. 150mA allows the use of the flash LED as a torch or video light Flash Mode: A high current of e.g. 700mA (up to 1000mA) is set for a high brightness flash. Only in this mode, the flash timeout timer limits the total flash time. Pulsed Indicator Mode (only AS3685A): The control device sends a short sequence to the AS3685A and the AS3685A enables the flash LED for a defined fixed duration (torch current setting). This duration is controlled by the AS3685A and the control device does not need to start an internal timer function. The current through the LED and the operating mode is controlled by the two digital pins EN1 and EN2. There are two versions of the AS3685 available: AS3685A and AS3685B. The only difference between these versions is the digital interface as shown below:
7.2.1 AS3685A Current Setting
For the AS3685A, the operating mode and the current through the LED is defined by the following table: Table 7 – AS3685A Current Settings ILED for RISET = EN1 EN2 Mode 14.2kΩ 10kΩ Percent of Full Scale ILED/IISET 0 0 Off 0mA 0mA 0% 0 (Off) 1 0 Indicator 4.7mA average (=150mA with 1/32 duty cycle1)) 6.7mA average (=214mA with 1/32 duty cycle1)) 0.67% (=21.4% / 32) 52.2 (=ITORCH2ISET/32) 0 1 Torch 150mA 214mA 21.4% 1639 (=ITORCH2ISET) 1 1 Flash 700mA 1000mA 100% 7650 (=IFLASH2ISET) Notes: 1) The on-time for indicator mode is 1 μs, off time 31μs (32μs = 32.25kHz) Where I ISET is: IISET VISET RISET 1.3V RISET ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 10 - 24 Application Hint: To obtain higher torch currents use the following circuit: Figure 13 – AS3685A Increasing Torch Current ISET VBAT EN1 EN2 VBAT EN1 EN2 RTORCH AS3685A RISET
7.2.1.1 AS3685A Pul sed Indicator Mode
The torch mode is controlled by EN1=0 and EN2=1 as following figure shows: Figure 14 – AS3685A Torch Mode EN2 EN1 offoff Torch Current ILED t typ. 64µs To allow an indication function using short pulses (with torch current settings), the pulsed indicator mode can be used. The control device sends a setup sequence (total time required: less than 128μs) to ‘program’ the AS3685A, and the AS3685A enables its current sink for the duration tTORCH (the current used is exactly the torch current setting). Therefore the control does not need to setup an timer to accurately define the duration of the indicator pulse. The duration t TORCH can be setup from 1ms to 15ms depending on the number of pulses on EN2 as shown in the following figure and table: ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 11 - 24 Figure 15 – AS3685A Pulsed Indicator Mode EN2 EN1 Set duration of Torch-Pulse (tTORCH) with number of pulses on pin EN2 offoff Torch Current ILED t typ. 64µs max. 128µs tTORCH min tPULSEWIDTH (1µs) Table 8 – AS3685A tTORCH timings H-L Pulses on EN2 tTORCH 1,2 0ms ignored (noise filter) 3 1ms 4 2ms 5 3ms 6 4ms 7 5ms 8 6ms 9 7ms 10 8ms 11 9ms 12 10ms 13 11ms 14 12ms 15 13ms 16 14ms ≥17 15ms ams AG Technical content still valid
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7.2.2 AS3685B Current Setting
The current through the LED (ILED) can be set in several steps using the following waveforms: Figure 16 – AS3685B Current Setting Method A For method A, the current is started after a certain time after the first rising edge of EN1. The AS3685B chooses method A, if EN1 is high at the first rising edge of EN2. Figure 17 – AS3685B Current Setting Method B For method B, the current is started after the second rising edge of EN2. The AS3685B chooses method B, if EN1 is low at the first rising edge of EN2. Any high or low level duration for EN1 or EN2 should not be shorter than t PULSEWIDTH. The actual number of pulses on the pin EN1 (applies for methods A and B) define the mode and the current settings for the AS3685B: Table 9 – AS3685B Current Settings H-L-H Pulses on EN1 Mode ILED (for RISET = 14.2kΩ) ILED (for RISET = 10kΩ) ILED/IISET EN1=EN2=0 Off 0mA 0% 0 (Off) Indicator 4.7mA average (=150mA with 1/32 duty cycle1) ) 6.7mA (=214mA with 1/32 duty cycle1)) 52.2 (=ITORCH2ISET/32) 2 41mA 60mA 448 3 85mA 120mA 929 4 129mA 180mA 1410 Torch 173mA 250mA 1891
6 Flash 217mA 310mA 2371
Flash/Strobe/Indicatior function dependent on number of pulses ILED t typ. 64µs Current can be increased if required Define Method A min. t PULSEWIDTH EN2 EN1 Set current with number of pulses offoff Flash/Strobe/Indicatior function dependent on number of pulses ILED t typ. 64µs Current can be increased if required no time limit Define Method B min tPULSEWIDTH ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 13 - 24 Table 9 – AS3685B Current Settings H-L-H Pulses on EN1 Mode ILED (for RISET = 14.2kΩ) ILED (for RISET = 10kΩ) ILED/IISET 7 261mA 370mA 2852 8 305mA 440mA 3333 9 349mA 500mA 3814 10 393mA 560mA 4295 11 437mA 620mA 4776 12 481mA 690mA 5257 13 525mA 750mA 5737 14 569mA 810mA 6218 15 613mA 880mA 6699 16 657mA 940mA 7180 Flash 700mA 1000mA 7650 (=IFLASH2ISET) Notes: 1) The on-time for indicator mode is 1μs, off time 31μs (32μs = 32.25kHz) Where I ISET is:
7.2.2.1 AS3685B Singl e Wire Interface
Using the following application schematic, a single GPIO pin can be used to control the mode and current of the AS3685B: Figure 18 – AS3685B Single Wire Interface An example driving waveform can be (this uses method A as shown above in section ‘AS3685B Current Settings’): Figure 19 – AS3685B Example Single Wire Interface driving waveform IISET VISET RISET 1.3V RISET (EN2) EN1 Set current with number of pulses offoff Flash/Strobe/Indicatior function dependent on number of previous pulses ISET VBAT EN1 EN2 Vbat EN1 single GPIO Pin to set indicator/torch/flash mode CSINGLE 1nF AS3685B RSINGLE ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 14 - 24 The low time of the pulses on EN1 for setting the current should be kept short. Then the (generated) signal on pin EN2 will stay at a high level during this time ensuring correct operation. RSINGLE should be chosen to fit to the actual driving waveform on EN1.
7.2.2.2 AS3685B Two Wire Interface with Strobe Input
Using the following application schematic, the AS3685B current and mode can be set accurately and the camera can directly control the exact strobe time: Figure 20 – AS3685B Two Wire Interface with strobe input An example driving waveform can be (this uses method B as shown above in section ‘AS3685B Current Settings’): Figure 21 – AS3685B Example Two Wire Interface driving waveform EN2 EN1 off STROBE off GPIO output driving EN2 directly is tristated and 'STROBE' defines input EN2 GPIO output driving EN2 directly defines input EN2 Set current with number of pulses Enable/Disable current directly by the camera module using the 'STROBE' input Flash/Strobe/Indicatior function dependent on number of previous pulses ISET VBAT EN1 EN2 Vbat EN1 EN2 Two GPIO Pins to set current and mode STROBE Optional Strobe Input AS3685B RSTROBE ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 15 - 24
7.2.3 AS3685A and AS3685B TXMask Function
If the battery has to supply two high currents at the same time (e.g. the AS3685 flash and a RF-power amplifier) it is possible, that the total current causes a high voltage drop on the battery resulting in a shutdown of the complete system. In order to avoid this shutdown, the AS3685 (AS3685A or AS3685B) can reduce its current with the signal ‘TXMask’ using the following circuit: Figure 22 – TXMask function of the AS3685 The TXMask signal is connected to e.g. the (RF-) power amplifier enable pin (active high if the PA is enabled). This reduces the flash current if the power amplifier is enabled and avoids the unexpected shutdown of the system. Note: The internal flash timeout timer (tFLASHTIMEOUT) to limit the total flash duration, is not affected by the TXMask function (see also section ‘Flash Timeout’). The IISET current (current into the pin ISET) for TXMask = 0 can be calculated with: For TXMask = 1 the current IISET is reduced to: V(TXMask) is the actual voltage for the high level (‘1’) for the signal TXMask The maximum flash current I LEDMAX for TXMask=0 or 1 can be calculated according to the following formula using the above obtained IISET values: Choose the values for RISET and RTXMASK according to your application requirements. ISET VBAT EN1 EN2 VBAT EN1 EN2 RISET RTXMASK AS3685A AS3685B TXMask IISET , TXMask 0 VISET RISET VISET RTXMASK 1.3 V RISET 1.3V RTXMASK IISET , TXMask 1 VISET RISET VISET V TXMask RTXMASK 1.3V RISET
1.3 V V TXMask
ILEDMAX IFLASH2BIAS IISET 7650 IISET ams AG Technical content still valid
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7.3 Protection Functions
7.3.1 Overtemperature Protection
If the AS3685 junction temperature exceeds TOVTEMP, the current sink will be disabled and the charge pump forced into 1:1 mode. If the junction temperature drops below TOVTEMP – TOVTEMPHYST, the device enables the current sink again and the charge pump resumes normal operation.
7.3.1.1 LED Shortcircuit protection
If the LED is shorted (VCP to ILED), then depending on the set current and the resulting high power dissipation inside the AS3685, the overtemperature protection will trigger. This protects the AS3685 and the system against damage. If the AS3685 is in off-mode, then shorting of the diode will have no influence on the system. Note: Do not short VCP to VSS if the supply is not current limited (e.g. by an internal protection inside the battery), as there is an internal diode between VBAT (anode) and VCP (cathode).
7.3.2 Flash Timeout
The flash duration of a single flash is limited automatically to tFLASHTIMEOUT (applies only for ‘Flash’ mode(s)). This protects the flash LED against thermal damage.
7.4 Layout Recommendations
To improve the heat dissipation, use a massive ground plane. Figure 23 – AS3685 DFN10 3x3mm Layout Recommendation Figure 24 – AS3685 WL-CSP 2x1.5mm Layout Recommendation AS3685 CVCP CBAT CFLY1 CFLY2 RISET VBAT VSS ILED VCP EN1 EN2 VIA, which is connected to the ground plane, too 'Normal' VIA Bottom Layer Top Layer Use ground place connected to VSS Use ground plane connected to VSS CFLY2 RISETA1 CBAT CVCP CFLY1 VSS VBAT EN1 VCP EN2 ILED VIA, which is connected to the ground plane, too 'Normal' VIA Micro VIA between AS3685 Bottom Layer Top Layer Inner Layer A1 A2 A3 B1 B2 B3 C1 C2 C3 D1 D2 D3 ams AG Technical content still valid
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8 External Components
8.1 Capacitor and Resistor Selection
Use low-ESR ceramic capacitors with X7R or X5R dielectric. These capacitors allow good filtering and have a wide temperature range. The connections of all external capacitors should be kept as short as possible. All resistors should have a tolerance of ±1%.
8.2 Usage of PCB Wire Inductance
The inductance between the battery and pin VBAT can be used as a filter to reduce disturbance on the battery. Instead of using one capacitor (CBAT) it is recommended to split CBAT into CBAT1 and CBAT2 with the capacitance of CBAT1 = CBAT2 = CBAT It is recommended to apply a minimum of 20nH (maximum 200nH) with low impedance. This inductance can be realized on the PCB without any discrete coil. Assuming that a 1mm signal line corresponds to approximately 1nH (valid if the length (L) is significantly bigger than the width (W) of the line (L/W <10)), a line length of 20mm < L < 200mm is recommended. The shape of the line is not important. Figure 25 – PCB Wire Inductance Example1 Figure 26 – PCB Wire Inductance Example2
8.3 External Component Specifications
Table 10 – External Components List Part Min Value Typ Max Tol (Min) Rating (Max) Notes Package (min) CBAT 1 2.2μF +/-20% 6.3V Ceramic, X5R e.g. Murata GRM21BR71A225KA01L 0603 CFLY1, CFLY2 1.0μF +/-20% 6.3V Ceramic, X5R e.g. Murata GRM188R60J105K 0603 (0402, 0405) CVCP 2.2μF +/-20% 6.3V Ceramic, X5R e.g. Murata GRM21BR71A225KA01L 0603 RISET 10kΩ 130kΩ +/-1% Current Set Resistor 0201 RTXMASK See section ‘TXMask function’ +/ -1% TXMask Set Resistor 0201 DLED Flash Led Notes: 1. See section ‘Usage of PCB Wire Inductance’ Battery Connector VSS VSS AS3685 Pin VBAT L CBAT1 CBAT2 LTOTAL = L Battery Connector VSS VSS AS3685 Pin VBAT CBAT1 CBAT2 LTOTAL = L1 + 10*L2 ams AG Technical content still valid
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9 Pinout and Packaging
9.1 DFN10 3x3mm
9.1.1 Pin Assignments DFN10 3x3mm
Figure 27 –Pin Assignments DFN10 3x3mm
9.1.2 Pin Descriptions DFN10 3x3mm
Table 11 – Pin Type Descriptions DFN10 3x3mm Pin Type Description AI/O Analog Pin DI Digital Input S Supply Pin Table 12 – Pin Descriptions DFN10 3x3mm Pin Number Pin Name Type Description
1 C2- AI/O Flying Capacitor 2 connection – connect 1μF ceramic
capacitor CFLY2 between C2- and C2+
2 VBAT S Battery Supply Voltage
3 C1+ AI/O Flying Capacitor 1 connection – connect 1μF ceramic
capacitor CFLY1 between C1- and C1+
4 VCP AI/O Charge Pump Output voltage – connect flash LED anode
to this pin and add CVCP capacitor with 2.2μF to VSS
5 EN1 DI Digital Control Signal EN1
6 ISET AI/O Current Generator input pin – connect current set resistor
RISET between this pin and VSS (and optional RTXMASK)
7 EN2 DI Digital Control Signal EN2
8 C2+ AI/O Flying Capacitor 2 connection – connect 1μF ceramic
capacitor CFLY2 between C2- and C2+
9 ILED AI/O Current Source input pin – connect flash LED cathode to
10 C1- AI/O Flying capacitor 1 connection – connect 1μF ceramic
capacitor CFLY1 between C1- and C1+ Exposed Pad VSS S Ground Connection – a proper thermal connection with several vias to the ground plane is recommended C1+ C1- C2+ C2- VCP ILED AS3685A AS3685B ISET VBAT EN1 EN2 VSS Exposed Pad ams AG Technical content still valid
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9.1.3 Package Drawings and Marking DFN10 3x3
Figure 28 – DFN10 – 3x3mm Pacakge Drawing Marking: Line 1: AYWW A = Pb-Free Identifier Y = Year WW = Week Line 2: XZZ X = Plant Identifier ZZ = Letters of Free Choice Line 3: AS8A for AS3685A or AS8B for AS3685B AYWW XZZ AS8x Bottom View (rotated) Top View ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 20 - 24 Figure 29 – DFN10 – 3x3mm Detail Dimensions ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 21 - 24 9.2 WL-CSP 2x1.5mm (Wafer Level Chip Scale Package) 9.2.1 Pin Assignments WL-CSP 2x1.5mm Figure 30 – WL-CSP 2x1.5mm Pin Assignments 9.2.2 Pin Descriptions WL-CSP 2x1.5mm Table 13 – Pin Type Descriptions WL-CSP 2x1.5mm Pin Type Description AI/O Analog Pin DI Digital Input S Supply Pin Table 14 – Pin Descriptions WL-CSP 2x1.5mm Pin Number Pin Name Type Description A1 EN1 DI Digital Control Signal EN1 A2 VSS S Ground Connection – a proper thermal connection to the ground plane is recommended A3 ISET AI/O Current Generator input pin – connect current set resistor R ISET between this pin and VSS (and optional RTXMASK) B1 C1+ AI/O Flying Capacitor 1 connection – connect 1μF ceramic capacitor CFLY1 between C1- and C1+ B2 VCP AI/O Charge Pump Output voltage – connect flash LED anode to this pin and add CVCP capacitor with 2.2μF to VSS B3 EN2 DI Digital Control Signal EN2 C1 VBAT S Battery Supply Voltage C2 C2+ AI/O Flying Capacitor 2 connection – connect 1μF ceramic capacitor CFLY2 between C2- and C2+ C3 ILED AI/O Current Source input pin – connect flash LED cathode to this pin D1 C2- AI/O Flying Capacitor 2 connection – connect 1μF ceramic capacitor CFLY2 between C2- and C2+ D2 C1- AI/O Flying capacitor 1 connection – connect 1μF ceramic capacitor CFLY1 between C1- and C1+ D3 VSS S Ground Connection – a proper thermal connection to the ground plane is recommended C1+ C1- C2+ C2- VCP ILED AS3685A AS3685B ISET VBAT EN1 EN2 VSS D1D2 A2,D3 ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 23 - 24 Table 15 – Delivery Information Part Number Marking Package Type Delivery Form Description AS3685A-ZWLT- 2N80 AS3685A WL-CSP 2x1.5mm Tape&Reel AS3685A Interface Wafer Level Chip Scale Package, Size 2x1.5mm, 4x3 balls, 0.5mm pitch, RoHS compliant / Pb-free, 800ms flash timeout, 1:2 mode locked AS3685A-ZWLT- 2Y80 AS3685A2 WL-CSP 2x1.5mm Tape&Reel AS3685A Interface Wafer Level Chip Scale Package, Size 2x1.5mm, 4x3 balls, 0.5mm pitch, RoHS compliant / Pb-free, 800ms flash timeout, 1:2 mode enabled1 AS3685A-ZDFT- 2Y80 AS8A DFN 10 3x3mm Tape&Reel AS3685A Interface pitch, RoHS compliant / Pb-free, 800ms flash timeout, 1:2 mode enabled1 AS3685B-ZDFT- 2Y80 AS8B DFN 10 3x3mm Tape&Reel AS3685B Interface pitch, Pb-Free, 800ms flash timeout, 1:2 mode enabled Description: AS3685V-ZPPT-2X80 AS3685 V … AS3685 Interface Version: A = AS3685A: Direct control to select three different currents B = AS3685B: Single or Two pin interface with strobe; 17 different current settings Z … Temperature range: Z = -30°C – 85°C PP … Package: WL = Wafer Level Chip Scale Package DF = DFN10 T … Delivery Form: T = Tape&Reel 2X … Charge Pump Mode Locking: 2N = 1:2 mode locked (device can only use 1:1 and 1:1.5 mode) 2Y = 1:2 mode available (device can use 1:1, 1:1.5 and 1:2 mode) 80 … Flash Timeout time programming 80 = 800ms flash timeout time
1 If 1000mA flash LED current is used it is usually required to allow 1:2 mode (due to the high forward
voltage of the LED). ams AG Technical content still valid
www.austriamicrosystems.com/AS3685 (ptr) Revision 2.2 24 - 24 Copyright Copyright © 1997-2010, austriamicrosystems AG, Tobelbaderstrasse 30, 8141 Unterpremstaetten, Austria- Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. All products and companies mentioned are trademarks or registered trademarks of their respective companies. Diclaimer Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for each application. For shipments of less than 100 parts the manufacturing flow might show deviations from the standard production flow, such as test flow or test location. The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However, austriamicrosystems AG shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of austriamicrosystems AG rendering of technical or other services Contact Information Headquarters austriamicrosystems AG Tobelbaderstrasse 30 Schloss Premstätten A-8141 Austria Tel: +43 (0) 3136 500 0 Fax: +43 (0) 3136 525 01 For Sales Offices, Distributors and Representatives, please visit: http://www.austriamicrosystems.com/contact ams AG Technical content still valid