ICS421-05 DIGITAL VIDEO CAMERA CLOCK Description Features The ICS421-05 is a low-power, low-jitter clock synthesizer developed for digital camera applications. The device accepts a 27 MHz input clock to support common digital video camera interface frequencies including a 12 MHz for USB, 24.576 MHz for IEEE1394, and a 72 MHz CCD clock. Power consumption was minimized by lowering the voltage requirement to 1.8 V minimum. • • • • • • • Ultra-low operating voltage from 1.8 V to 2.4 V 10 mA supply current 27 MHz input clock frequency Fixed 24.576 MHz clock supports IEEE1394 Fixed 12 MHz clock supports USB Fixed 72 MHz CCD clock Packaged in 8-pin TSSOP (Pb free) The ICS421-05 utilizes a small form factor 8-pin TSSOP package. ICS is a leader in low power, consumer application clock sources. Devices are capable of supporting CCD, video, audio, USB, CPU, and other peripherals. Block Diagram VDD 2 IEEE PLL 27 MHz Input Clock 24.576M Clock Buffer CLKIN 72M CCD/ USB PLL 12M 1 OE_USB GND 1 MDS 421-05 B I nt eg ra te d C ir c uit S y s t em s ● 525 Ra ce St reet, San Jose, C A 95 126 Revision 072304 ● tel (40 8) 2 97-12 01 ● w w w. i c st . c o m ICS421-05 DIGITAL VIDEO CAMERA CLOCK Pin Assignment OE_USB Operation Table CLKIN VDD 1 2 8 7 OE_USB 12M GND 24.576M 3 4 6 5 VDD 72M OE_USB Function 0 Output tri-state 1 Output running 8 pin (173 mil) TSSOP Pin Descriptions Pin Number Pin Name Pin Type Pin Description 1 2 3 4 5 6 7 8 CLKIN VDD GND 24.576M 72M VDD 12M OE_USB Input Power Power Output Output Power Output Input 27 MHz single ended clock input. Connect to voltage supply. Connect to ground. 24.576 MHz clock output. 72 MHz clock output for CCD. Connect to voltage supply. 12 MHz clock output for USB. Output enable for 12M clock for USB. See table for functionality, internal pull-down. External Components Series Termination Resistor Clock output traces over one inch should use series termination. To series terminate a 50Ω trace (a commonly used trace impedance), place a 33Ω resistor in series with the clock line, as close to the clock output pin as possible. The nominal impedance of the clock output is 20Ω. Decoupling Capacitor As with any high-performance mixed-signal IC, the ICS421-05 must be isolated from system power supply noise to perform optimally. A decoupling capacitor of 0.01µF must be connected between VDD and the PCB ground plane. PCB Layout Recommendations For optimum device performance and lowest output phase noise, the following guidelines should be observed. 2) To minimize EMI, the 33Ω series termination resistor (if needed) should be placed close to the clock output. 3) An optimum layout is one with all components on the same side of the board, minimizing vias through other signal layers (the ferrite bead and bulk decoupling capacitor can be mounted on the back). Other signal traces should be routed away from the ICS421-05. This includes signal traces just underneath the device, or on layers adjacent to the ground plane layer used by the device. 2 MDS 421-05 B In te grated Circui t Systems 1) The 0.01µF decoupling capacitor should be mounted on the component side of the board as close to the VDD pin as possible. No vias should be used between decoupling capacitor and VDD pin. The PCB trace to VDD pin should be kept as short as possible, as should the PCB trace to the ground via. Distance of the ferrite bead and bulk decoupling from the device is less critical. ● 52 5 R ace St reet, San Jose , CA 9 5126 Revision 072304 ● te l (4 08) 297 -1 201 ● www.icst.com ICS421-05 DIGITAL VIDEO CAMERA CLOCK Absolute Maximum Ratings Stresses above the ratings listed below can cause permanent damage to the ICS421-05. These ratings, which are standard values for ICS commercially rated parts, are stress ratings only. Functional operation of the device at these or any other conditions above those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods can affect product reliability. Electrical parameters are guaranteed only over the recommended operating temperature range. Item Rating Supply Voltage, VDD -0.5 V to 7 V All Inputs and Outputs -0.5 V to VDD +0.5 V Ambient Operating Temperature 0 to +70 °C Storage Temperature -65 to +150 °C Junction Temperature 125 °C Soldering Temperature 260 °C Recommended Operating Conditions Parameter Min. Typ. Max. Units 0 – +70 °C +2.4 V Ambient Operating Temperature Power Supply Voltage (measured in respect to GND) +1.8 DC Electrical Characteristics VDD = 1.8 V to 2.4 V, Ambient Temperature 0 to +70°C, unless stated otherwise Parameter Symbol Conditions Operating Voltage VDD Input High Voltage VIH CLKIN Input Low Voltage VIL CLKIN Input High Voltage VIH OE_USB pin Input Low Voltage VIL OE_USB pin Output High Voltage VOH VDD = 2.4 V, IOH = -4 mA Output Low Voltage VOL VDD = 2.4 V, IOL = 4 mA Output High Voltage VOH VDD = 1.8 V IOH = -4 mA Output Low Voltage VOL VDD = 1.8 V IOL = 4 mA Operating Supply Current IDD No load, 3 out Typ. 1.80 ● 52 5 R ace St reet, San Jose , CA 9 5126 Max. Units 2.40 V VDD/2+0.5 V VDD/2-0.5 TBD V V TBD 1.9 V V 0.4 1.4 V V 0.4 10 V mA 3 MDS 421-05 B In te grated Circui t Systems Min. Revision 072304 ● te l (4 08) 297 -1 201 ● www.icst.com ICS421-05 DIGITAL VIDEO CAMERA CLOCK Parameter Symbol Short Circuit Current IOS Nominal Output Impedance Zo Conditions Min. Typ. Each output On-chip Pull-down Resistor OE_USB Notes: 1. Nominal switching threshold is VDD/2 Max. Units 50 mA 20 W 150 kΩ AC Electrical Characteristics VDD = 1.8 V to 2.4 V, Ambient Temperature 0 to +70°C, unless stated otherwise Parameter Symbol Input Frequency Conditions Min. Typ. Max. Units Clock Input 27 MHz Output Rise Time tOR VDD=2.4 V, 20% to 80%, CL=10 pF 1.8 ns Output Fall Time tOF VDD=2.4 V, 80% to 20%, CL=10 pF 1.8 ns Output Rise Time tOR VDD=1.8 V, 20% to 80%, CL=10 pF 2.5 ns Output Fall Time tOF VDD=1.8 V, 80% to 20%, CL=10 pF 2.5 ns Output Clock Duty Cycle at VDD/2 50 % Absolute Pk-Pk Jitter 72 MHz output clock ±200 ps PLL Lock Time within 1% Power OFF to lock 10 ms Thermal Characteristics Parameter Symbol Conditions Min. Typ. Max. Units Thermal Resistance Junction to Ambient θJA Still air 110 °C/W θJA 1 m/s air flow 100 °C/W θJA 3 m/s air flow 80 °C/W Thermal Resistance Junction to Case θJC 35 °C/W Marking Diagram 8 Notes: 5 1. ###### is the lot code. YYWW 21G5L ###### 1 3. “L” designates Pb (lead) free package. 4 4 MDS 421-05 B In te grated Circui t Systems 2. YYWW is the last two digits of the year, and the week number that the part was assembled. ● 52 5 R ace St reet, San Jose , CA 9 5126 Revision 072304 ● te l (4 08) 297 -1 201 ● www.icst.com ICS421-05 DIGITAL VIDEO CAMERA CLOCK Package Outline and Package Dimensions (8-pin TSSOP, 173 Mil. Body) Package dimensions are kept current with JEDEC Publication No. 95 Millimeters 8 Symbol E1 INDEX AREA Min A A1 A2 b C D E E1 e L α aaa E 1 D Inches Max Min -1.20 0.05 0.15 0.80 1.05 0.19 0.30 0.09 0.20 2.90 3.10 6.40 BASIC 4.30 4.50 0.65 Basic 0.45 0.75 0° 8° -0.10 Max -0.047 0.002 0.006 0.032 0.041 0.007 0.012 0.0035 0.008 0.114 0.122 0.252 BASIC 0.169 0.177 0.0256 Basic 0.018 0.030 0° 8° -0.004 A A2 A1 c - Ce SEATING PLANE b L aaa C Ordering Information Part / Order Number ICS421G-05LF ICS421G-05LFT Marking Shipping Packaging Package Temperature 21G5L Tubes Tape & Reel 8-pin TSSOP 8-pin TSSOP 0 to +70 °C 0 to +70 °C “LF” denotes Pb (lead) free package. While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems (ICS) assumes no responsibility for either its use or for the infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial applications. Any other applications such as those requiring extended temperature range, high reliability, or other extraordinary environmental requirements are not recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for use in life support devices or critical medical instruments. 5 MDS 421-05 B In te grated Circui t Systems ● 52 5 R ace St reet, San Jose , CA 9 5126 Revision 072304 ● te l (4 08) 297 -1 201 ● www.icst.com