CF5008A1 VCXO Module IC NIPPON PRECISION CIRCUITS INC. OVERVIEW The CF5008A1 is a VCXO module IC that employs a circuit structure with low parasitic capacitance effects and a wide frequency range. Built-in components mean that few external components are required to construct a VCXO. FEATURES ■ ■ ■ ■ ■ ■ ■ ■ Up to 30 MHz operation Inverter amplifier feedback resistor built-in 8 mA (VDD = 5 V), 4 mA (VDD = 3 V) drive capability 2.7 to 5.5 V supply voltage Circuit structure with low parasitic capacitance effects • Direct connection to varicap diodes and crystal Few external components required to form a VCXO Amplitude limiting resistor Rd built-in Chip form (CF5008A1) SERIES CONFIGURATION Version Output frequency Input level Output duty level S t a n d by output state CF5008A1 fO CMOS CMOS High impedance ORDERING INFORMATION D e vice P ackag e C F 5 0 0 8 A 1 –2 Chip form NIPPON PRECISION CIRCUITS—1 CF5008A1 PAD LAYOUT (Unit : µm) UNUSED2 VDD INH XT2 UNUSED1 1 8 2 3 4 7 (1400,1300) 5 6 (0,0) VSS XT Q Chip size: 1.40 × 1.30 mm Chip thickness: 220 ± 30 µm Chip base: V D D level PAD DIMENSIONS Number Name I/O 1 UNUSED1 – 2 UNUSED2 – Description P ad dimensions [µm] X Y Not used. 153 1112 Not used. 425 1112 3 XT2 O Oscillator output pin 660 1112 4 VDD – Supply voltage 865 1112 5 INH I Output-control input pin. Q signal output enabled when HIGH or open. High-impedance output when LOW . 1202 1112 6 Q O Output pin 1245 152 7 XT I Oscillator input pin 346 188 8 VSS – Ground 155 188 NIPPON PRECISION CIRCUITS—2 CF5008A1 BLOCK DIAGRAM Rf CG VDD XT VSS CD Rd Q CC Rp XT2 Control Circuits INH RB2 OSCILLATOR ELEMENT CONSTANTS (typical values) CF5008A1 R B1 R B2 Rd Rf Rp CG CD CC 100k Ω 50k Ω 450 Ω 150k Ω 100k Ω 20pF 10pF 70pF NIPPON PRECISION CIRCUITS—3 CF5008A1 SPECIFICATIONS Absolute Maximum Ratings VSS = 0 V P arameter Symbol Condition Rating Unit Supply voltage range VDD −0.5 to 7.0 V Input voltage range V IN −0.5 to V D D + 0.5 V VOUT −0.5 to V D D + 0.5 V Operating temperature range T opr −40 to 85 °C Storage temperature range T stg −65 to 150 °C Output current IO U T 25 mA Output voltage range Recommended Operating Conditions VSS = 0 V, CL ≤ 15 pF, f ≤ 32.5 MHz Rating P arameter Symbol Condition Unit min typ max Supply voltage VDD 2.7 – 5.5 V Input voltage V IN VSS – VDD V TO P R −20 – 80 °C Operating temperature NIPPON PRECISION CIRCUITS—4 CF5008A1 Electrical Characteristics VDD = 4.5 to 5.5 V, VSS = 0 V, Ta = −20 to 80 °C unless otherwise noted. Rating P arameter Symbol Condition Unit min typ max HIGH-level output voltage VOH Q: Measurement cct 1, I O H = 8 mA, V D D = 4.5 V 4.0 4.2 – V L O W -level output voltage VOL Q: Measurement cct 1, I O L = 8 mA, V D D = 4.5 V – 0.3 0.4 V Q: Measurement cct 2, I N H = L O W , V O H = V D D – – 10 Q: Measurement cct 2, I N H = L O W , V O L = V S S – – 10 Output leakage current IZ µA HIGH-level input voltage V IH INH 0.8V D D – – V L O W -level input voltage V IL INH – – 0.2V D D V Current consumption ID D I N H = open, Measurement cct 3, load cct 1, C L = 15 p F, f = 30 M H z – 28 65 mA I N H pull-up resistance RUP Measurement cct 4 50 – 150 kΩ Feedback resistance Rf Design value, determined by the internal wafer pattern – 150 – kΩ – 450 – Ω – 0 – Ω Rd Design value, determined by the internal wafer pattern Rc Built-in resistance R B1 Measurement cct 5 – 100 – kΩ R B2 Measurement cct 6 – 50 – kΩ – 20 – pF – 10 – pF – 70 – pF CG Built-in capacitance CD Design value, determined by the internal wafer pattern CC Switching Characteristics VDD = 2.7 to 5.5 V, VSS = 0 V, Ta = −20 to 80 °C unless otherwise noted. Rating P arameter Symbol Output rise time Output fall time Output duty cycle 1 Condition tr1 Measurement cct 3, load cct 1, 0.1V D D to 0.9V D D , C L = 15 p F tf1 Measurement cct 3, load cct 1, 0.9V D D to 0.1V D D , C L = 15 p F Duty Output disable delay time tP L Z Output enable delay time tP Z L Measurement cct 3, load cct 1, Ta = 25 °C , C L = 15 p F, f = 3 2 M H z Unit min typ max V D D = 2.7 to 3.6 V – 3 8 V D D = 4.5 to 5.5 V – 2.5 6 V D D = 2.7 to 3.6 V – 3 8 V D D = 4.5 to 5.5 V – 2.5 6 V D D = 3.0 V 42 – 58 V D D = 5.0 V 42 – 58 – – 100 ns – – 100 ns ns ns % Measurement cct 7, load cct 1, Ta = 25 °C , C L ≤ 15 p F 1. Determined by the lot monitor. Current consumption and Output waveform with NPC’s standard crystal Cb L Ca f (MHz) R (Ω) L (mH) Ca (fF) Cb (pF) 30 17.2 4.36 6.46 2.26 R NIPPON PRECISION CIRCUITS—5 CF5008A1 FUNCTIONAL DESCRIPTION Standby Function The oscillator output on Q changes as shown in the following table when INH goes LOW. INH Q Oscillator HIGH (or open) fO Nor mal operation LOW High impedance Nor mal operation TYPICAL APPLICATION CIRCUIT Typical circuit structures (CG and CD) that use a varicap device have a reduced frequency range due to the effects of parasitic capacitance. The CF5008A1, however, has built-in components CC and RB2 that are connected in series with the varicap device, increasing the frequency output range. VCXO Module Rf VDD CG XT VSS X'tal CD VCC GND Rd Control Input Q Output CC VARI−CAP Rp XT2 Control Circuits RB2 INH Output Enable CF5008 PARASITIC CAPACITANCE Parasitic capacitance are unwanted capacitance effects that occur due to the junction capacitance where the protection diodes and transistor drains are connected to the substrate. The following equivalent circuit figure shows the calculated parasitic capacitances. The surface area for each component is calculated from the IC layout pattern, and the capacitance calculated per unit area. Rf 150k XT 5.01p CG 20p 2.4p Divider (1/1) VDD Rd VSS CD 10p CC 70p XT2 4.7p RB2 50k Q Control Circuits Rp 100k INHN NIPPON PRECISION CIRCUITS—6 CF5008A1 VARICAP (Variable Capacitance Diodes) SELECTION The CF5008A1 forms a VCXO with addition of an external varicap (variable capacitance diode) device. This section examines the results using various varicap devices. When the equivalent circuit in figure 1 is used, the load capacitance CL must be changed by a factor of 4 to 5 (10 to 40pF) to affect a ±100ppm frequency change. Varicap devices that can change the capacitance by a factor of 5 require a maximum capacitance in the range approximately 20 to 50pF. Devices matching this criteria are listed in the following table. L 4.08673mH Ca 7.56439fF R 17.7068Ω Cb 2.05389pF Frequency:28.633MHz C L :20pF Figure 1. Crystal oscillator element equivalent circuit Company Product Capacitance 1 Capacitance 2 HITA C H I HVU17 50.0 to 85.0pF (VR = 1V) 5.23 to 8.84pF (VR = 4.5V) HITA C H I HVU359 24.8 to 29.8pF (VR = 1V) 6.00 to 8.30pF (VR = 4V) HITA C H I HVU362 41.6 to 49.9pF (VR = 1V) 10.1 to 14.8pF (VR = 4V) HITA C H I HVC374B 21.5 to 24.0pF (VR = 1V) 12.5 to 14.5pF (VR = 2V) HITA C H I HVC375B 15.5 to 17.0pF (VR = 1V) 4.0pF typ (VR = 4V) P anasonic MA304 24.8 to 29.8pF (VR = 1V) 6.00 to 8.30pF (VR = 4V) P anasonic MA2S304 24.8 to 29.8pF (VR = 1V) 6.00 to 8.30pF (VR = 4V) P anasonic MA2ZV05 18.5 to 20.5pF (VR = 1V) 3.60 to 4.10pF (VR = 4V) TO K O KV1811E 21.5pF typ (VR = 1V) 4.00pF typ (VR = 4V) TO K O KV1812 16.0pF typ (VR = 1V) 3.00pF typ (VR = 4V) NIPPON PRECISION CIRCUITS—7 CF5008A1 MEASUREMENT CIRCUITS Measurement cct 1 Measurement cct 4 When measuring VOL Signal Generator XT INH Q R1 VSS When measuring VOH R2 A RUP = VDD IRUP RB1 = VDD IRB1 RB2 = VDD IRB2 VSS IRUP VDD XT input waveform (10MHz) 0V Q output VDD VOH 0V Q output VDD VOL 0V C1 R1 R2 R3 VDD R3 VDD C1 Measurement cct 5 A IRB1 : 0.001µF : 50Ω : 500Ω : 512.5Ω VDD XT1 VCNOT VSS Measurement cct 2 IZ IZ VDD Measurement cct 6 A Q INH VSS V VDD A IRB2 XT2 VSS Measurement cct 3 Measurement cct 7 IDD A XT VDD X'tal VDD Q C3 XT2 INH VSS C1 Signal Generator XT R1 Q VSS INH C3 : 15pF C1 : 0.001µF R1 : 50Ω NIPPON PRECISION CIRCUITS—8 CF5008A1 Load cct 1 Q output CL (Including probe capacity) C L = 15pF : ID D , DUTY, tr1 , tf1 Switching Time Measurement Waveform Output duty level (CMOS) Q output 0.9VDD 0.9VDD 0.1VDD DUTY measuring voltage (0.5V DD) 0.1VDD TW tr tf Output duty cycle (CMOS) DUTY measuring voltage (0.5V DD) Q output TW DUTY= TW/ T T 100 (%) Output Enable/Disable Delay INH VIH VIL tPZL tPLZ Q output INH inputwaveform tr = tf 10ns NIPPON PRECISION CIRCUITS—9 CF5008A1 NIPPON PRECISION CIRCUITS INC. reserves the right to make changes to the products described in this data sheet in order to improve the design or performance and to supply the best possible products. Nippon Precision Circuits Inc. assumes no responsibility fo r the use of any circuits shown in this data sheet, conveys no license under any patent or other rights, and makes no claim that the circuits are free from patent infringement. Applications for any devices shown in this data sheet are for illustration only and Nippon Precision Circuits Inc. makes no claim or warranty that such applications will be suitable for the use specified without further testing or modification. The products described in this data sheet are not intended to use for the apparatus which influence human lives due to the failure or malfunction of the products. Customers are requested to comply with applicable laws and regulations in effect now and hereinafter, including compliance with expor t controls on the distribution or dissemination of the products. Customers shall not expor t, directly or indirectly, any products without first obtaining required licenses and approvals from appropriate government agencies. NIPPON PRECISION CIRCUITS INC. NIPPON PRECISION CIRCUITS INC. 4-3, Fukuzumi 2-chome Koto-ku, Tokyo 135-8430, Japan Telephone: 03-3642-6661 Facsimile: 03-3642-6698 NC9816AE 1999.09 NIPPON PRECISION CIRCUITS—10