INTEGRATED CIRCUITS DATA SHEET For a complete data sheet, please also download: • The IC04 LOCMOS HE4000B Logic Family Specifications HEF, HEC • The IC04 LOCMOS HE4000B Logic Package Outlines/Information HEF, HEC HEF4521B MSI 24-stage frequency divider and oscillator Product specification File under Integrated Circuits, IC04 January 1995 Philips Semiconductors Product specification 24-stage frequency divider and oscillator operation as a crystal oscillator is enabled by connecting external resistors to pins 3 (VSS’) and 5 (VDD’). Each flip-flop divides the frequency of the previous flip-flop by two, consequently the HEF4521B will count up to 224 = 16777216. The counting advances on the HIGH to LOW transition of the clock (I2). The outputs of the last seven stages are available for additional flexibility. DESCRIPTION The HEF4521B consists of a chain of 24 toggle flip-flops with an overriding asynchronous master reset input (MR), and an input circuit that allows three modes of operation. The single inverting stage (I2/O2) will function as a crystal oscillator, or in combination with I1 as an RC oscillator, or as an input buffer for an external oscillator. Low-power Fig.1 Functional diagram. FAMILY DATA, IDD LIMITS category MSI See Family Specifications January 1995 HEF4521B MSI 2 Philips Semiconductors Product specification HEF4521B MSI 24-stage frequency divider and oscillator COUNT CAPACITY OUTPUT Fig.2 Pinning diagram. COUNT CAPACITY O18 218 = 262 144 O19 219 = 524 288 O20 220 = 1 048 576 O21 221 = 2 097 152 O22 222 = 4 194 304 O23 223 = 8 388 608 O24 224 = 16 777 216 HEF4521BP(N): 16-lead DIL; plastic (SOT38-1) HEF4521BD(F): 16-lead DIL; ceramic (cerdip) (SOT74) HEF4521BT(D): 16-lead SO; plastic (SOT109-1) ( ): Package Designator North America FUNCTIONAL TEST SEQUENCE CONTROL TERMINALS INPUTS OUTPUTS REMARKS MR I2 O2 VSS’ VDD’ O18 to O24 H L L VDD VSS L counter is in three 8-stage sections in parallel mode; I2 and O2 are interconnected (O2 is now input); counter is reset by MR VDD VSS H 255 pulses are clocked into I2, O2 (the counter advances on the LOW to HIGH transition) L L L L VSS VSS H VSS’ is connected to VSS L H L VSS VSS H the input I2 is made HIGH L H L VSS VDD H VDD’ is connected to VDD; O2 is now made floating and becomes an output; the device is now in the 224 mode VSS VDD L L A test function has been included for the reduction of the test time required to exercise all 24 counter stages. This test function divides the counter into three 8-stage sections by connecting VSS’ to VDD and VDD’ to VSS. Via I2 (connected to O2) 255 counts are loaded into each of the 8-stage sections in parallel. All flip-flops are now at a HIGH state. January 1995 counter ripples from an all HIGH state to an all LOW state The counter is now returned to the normal 24-stage in series configuration by connecting VSS’ to VSS and VDD’ to VDD. One more pulse is entered into input I2, which will cause the counter to ripple from an all HIGH state to an all LOW state. 3 This text is here in white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader.This text is here in _white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader.This text is here inThis text is here in white to force landscape pages to be rotated correctly when browsing through the pdf in the Acrobat reader. white to force landscape pages to be ... Philips Semiconductors 4 24-stage frequency divider and oscillator January 1995 Product specification HEF4521B MSI Fig.3 Logic diagram; for schematic diagram of clock circuit see Fig.4. Philips Semiconductors Product specification HEF4521B MSI 24-stage frequency divider and oscillator Fig.4 Schematic diagram of clock input circuitry. AC CHARACTERISTICS VSS = 0 V; Tamb = 25 °C; CL = 50 pF; input transition times ≤ 20 ns VDD V SYMBOL MIN. TYP. TYPICAL EXTRAPOLATION FORMULA MAX. Propagation delays I2 → O18 HIGH to LOW LOW to HIGH On → On + 1 HIGH to LOW LOW to HIGH MR → On HIGH to LOW I1 → O1 HIGH to LOW LOW to HIGH 5 950 ns 923 ns + (0,55 ns/pF) CL 350 700 ns 339 ns + (0,23 ns/pF) CL 15 220 440 ns 212 ns + (0,16 ns/pF) CL 5 950 1900 ns 923 ns + (0,55 ns/pF) CL 350 700 ns 339 ns + (0,23 ns/pF) CL 15 220 440 ns 212 ns + (0,16 ns/pF) CL 5 40 80 ns 13 ns + (0,55 ns/pF) CL 15 30 ns 4 ns + (0,23 ns/pF) CL 10 10 10 tPHL tPLH tPHL 15 10 20 ns 2 ns + (0,16 ns/pF) CL 5 40 80 ns 13 ns + (0,55 ns/pF) CL 15 30 ns 4 ns + (0,23 ns/pF) CL 10 tPLH 15 10 20 ns 2 ns + (0,16 ns/pF) CL 5 120 240 ns 93 ns + (0,55 ns/pF) CL 55 110 ns 44 ns + (0,23 ns/pF) CL 10 tPHL 15 40 80 ns 32 ns + (0,16 ns/pF) CL 5 90 180 ns 63 ns + (0,55 ns/pF) CL 35 70 ns 24 ns + (0,23 ns/pF) CL 10 tPHL 15 25 50 ns 17 ns + (0,16 ns/pF) CL 5 60 120 ns 33 ns + (0,55 ns/pF) CL 30 60 ns 19 ns + (0,23 ns/pF) CL 20 40 ns 12 ns + (0,16 ns/pF) CL 10 tPLH 15 January 1995 1900 5 Philips Semiconductors Product specification HEF4521B MSI 24-stage frequency divider and oscillator VDD V Output transition times HIGH to LOW LOW to HIGH SYMBOL MIN. TYP. 5 TYPICAL EXTRAPOLATION FORMULA MAX. 60 120 ns 10 ns + (1,0 ns/pF) CL 30 60 ns 9 ns + (0,42 ns/pF) CL 15 20 40 ns 6 ns + (0,28 ns/pF) CL 5 60 120 ns 10 tTHL 10 tTLH 15 10 ns + (1,0 ns/pF) CL 30 60 ns 9 ns + (0,42 ns/pF) CL 20 40 ns 6 ns + (0,28 ns/pF) CL AC CHARACTERISTICS VSS = 0 V; Tamb = 25 °C; CL = 50 pF; input transition times ≤ 20 ns VDD V Minimum I2 pulse 5 width; HIGH 10 Minimum MR pulse width; HIGH Recovery time for MR Maximum clock pulse frequency SYMBOL TYP. MAX. 80 40 ns 40 20 ns 15 30 15 ns 5 70 35 ns 40 20 ns 15 30 15 ns 5 20 −10 ns tWI2H 10 tWMRH 15 −5 ns 15 15 0 ns 5 6 12 MHz 12 25 MHz 17 35 MHz 10 tRMR 10 fmax 15 VDD V Dynamic power MIN. 5 see also waveforms Fig.5 TYPICAL FORMULA FOR P (µW) 1 200 fi + ∑ (foCL) × VDD2 where fi = input freq. (MHz) dissipation per 10 5 100 fi + ∑ (foCL) × package (P) 15 13 050 fi + ∑ (foCL) × VDD2 VDD2 fo = output freq. (MHz) CL = load capacitance (pF) ∑ (foCL) = sum of outputs VDD = supply voltage (V) January 1995 6 Philips Semiconductors Product specification 24-stage frequency divider and oscillator HEF4521B MSI Fig.5 Waveforms showing minimum pulse widths for MR and I2, recovery time for MR. January 1995 7 Philips Semiconductors Product specification HEF4521B MSI 24-stage frequency divider and oscillator APPLICATION INFORMATION (1) Optional for low power operation. Fig.6 Crystal oscillator circuit. Typical characteristics for crystal oscillator circuit (Fig.6): 500 kHz CIRCUIT 50 kHz CIRCUIT UNIT Crystal characteristics resonance frequency 500 50 kHz crystal cut S N − equivalent resistance; RS 1 6,2 kΩ Ro 47 750 kΩ CT 82 82 pF CS 20 20 pF External resistor/capacitor values January 1995 8 Philips Semiconductors Product specification HEF4521B MSI 24-stage frequency divider and oscillator Fig.7 RC oscillator circuit; 1 f ≈ ------------------------------------ ; R S ≥ 2 R TC, in which: 2,3 × R TC × C f in Hz, R in Ω, C in F. V IL max R S + R TC < -----------------I LI ( maximum input voltage LOW ) ( input leakage current ) RTC; C = 1 nF; RS ≈ 2 RTC C; RTC = 56 kΩ; RS = 120 kΩ Fig.8 January 1995 9 Oscillator frequency as a function of RTC and C; VDD = 10 V; test circuit is Fig.7. Philips Semiconductors Product specification 24-stage frequency divider and oscillator Fig.9 HEF4521B MSI Test set-up for measuring forward transconductance gfs = dio/dvi at vo is constant (see also graph Fig.10). A: average, B: average + 2 s, C: average − 2 s, in which: ‘s’ is the observed standard deviation. Fig.10 Typical forward transconductance gfs as a function of the supply voltage at Tamb = 25 °C. January 1995 10 Philips Semiconductors Product specification HEF4521B MSI 24-stage frequency divider and oscillator Fig.11 Voltage gain VO/VI as a function of supply voltage. Fig.12 Supply current as a function of supply voltage. Fig.13 Test set-up for measuring graphs of Figs 11 and 12. January 1995 11 WWW.ALLDATASHEET.COM Copyright © Each Manufacturing Company. All Datasheets cannot be modified without permission. This datasheet has been download from : www.AllDataSheet.com 100% Free DataSheet Search Site. Free Download. No Register. Fast Search System. www.AllDataSheet.com