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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

HEF4541B MSI Programmable timer
Product specification File under Integrated Circuits, IC04 January 1995

Philips Semiconductors

Product specification

Programmable timer
DESCRIPTION The HEF4541B is a programmable timer which consists of a 16-stage binary counter, an integrated oscillator to be used with external timing components, an automatic power-on reset and output control logic. The frequency of the oscillator is determined by the external components Rt and Ct within the frequency range 1 Hz to 100 kHz. This oscillator may be replaced by an external clock signal at input RS, the timer advances on the positive-going transition of RS. A LOW on the auto reset input (AR) and a LOW on the master reset input (MR) enables the internal power-on reset. A HIGH level at input MR resets the counter independent on all other inputs. Resetting

HEF4541B MSI
disables the oscillator to provide no active power dissipation. A HIGH at input AR turns off the power-on reset to provide a low quiescent power dissipation of the timer. The 16-stage counter divides the oscillator frequency by 28, 210, 213 or 216 depending on the state of the address inputs (A0, A1). The divided oscillator frequency is available at output O. The phase input (PH) features a complementary output signal. If the mode select input (MODE) is LOW or HIGH the timer can be used respectively as a single transition timer or 2n frequency divider.

Fig.1 Functional diagram.

HEF4541BP(N): HEF4541BD(F): HEF4541BT(D):

14-lead DIL; plastic (SOT27-1) 14-lead DIL; ceramic (cerdip) (SOT73) 14-lead SO; plastic (SOT108-1)

( ): Package Designator North America FAMILY DATA, IDD LIMITS category MSI Fig.2 Pinning diagram. See Family Specifications

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Philips Semiconductors

Product specification

Programmable timer

HEF4541B MSI

Fig.3 Logic diagram.

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Philips Semiconductors

Product specification

Programmable timer
PINNING A0, A1 MODE AR MR PH RTC CTC RS address inputs mode select input auto reset input master reset input phase input external resistor connection (Rt) external capacitor connection (Ct) external resistor connection (RS) or external clock input AR H L X X X X FREQUENCY SELECTION TABLE X A0 L L H H A1 L H L H NUMBER OF COUNTER STAGES n 13 10 8 16 f osc n -------- = 2 f out 8 192 1 024 256 65 536 L H X FUNCTION TABLE INPUTS MODE MR L L H L L L PH X X X X X L MODE X X X H L X

HEF4541B MSI

auto reset disabled auto reset enabled (1) master reset active normal operation selected division to output single-cycle mode (2) output initially LOW, after reset output initially HIGH, after reset

Notes 1. For correct power-on reset, the supply voltage should be above 8.5 V. For VDD < 8.5 V, disable the autoreset and connect AR to VDD. 2. The timer is initialized on a reset pulse and the output changes state after 2n-1 counts and remains in that state (latched). Reset of this latch is obtained by master reset or by a LOW to HIGH transition on the MODE input. H = HIGH state (the more positive voltage) L = LOW state (the less positive voltage) X = state is immaterial

RC oscillator

Timing component limitations The oscillator frequency is mainly determined by RtCt, provided Rt << RS and RSC2 << RtCt. The function of RS is to minimize the influence of the forward voltage across the input protection diodes on the frequency. The stray capacitance C2 should be kept as small as possible. In consideration of accuracy, Ct must be larger than the inherent stray capacitance. Rt must be larger than the LOCMOS `ON' resistance in series with it, which typically is 500 at VDD = 5 V, 300 at VDD = 10 V and 200 at VDD = 15 V. The recommended values for these components to maintain agreement with the typical oscillation formula are: Ct 100 pF, up to any typical value, 10 k Rt 1 M.

Typical formula for oscillator frequency: 1 f osc = --------------------------------2, 3 × R t × C t

Fig.4

External component connection for RC oscillator; RS 2 Rt.

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Philips Semiconductors

Product specification

Programmable timer

HEF4541B MSI

Ct curve at Rt = 56 k; RS = 120 k. - - - Rt curve at Ct = 1 nF; RS = 2 Rt.

Fig.5 RC oscillator frequency as a function of Rt and Ct at VDD = 5 to 15 V; Tamb = 25 °C.

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Philips Semiconductors

Product specification

Programmable timer

HEF4541B MSI

Rt = 56 k; Ct = 1 nF; RS = 0. - - - Rt = 56 k; Ct = 1 nF; RS = 120 k.

Fig.6

Frequency deviation (f) as a function of ambient temperature; referenced at : fosc at Tamb = 25 °C and VDD = 10 V.

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Philips Semiconductors

Product specification

Programmable timer
DC CHARACTERISTICS VSS = 0 V Tamb (°C) VDD V Supply current power-on reset enabled (note) Supply voltage for automatic reset initialization (note) Output current HIGH; CTC, RTC 5 10 15 5 Output current LOW; CTC, RTC 5 10 15 Note 1. All inputs at 0 V or VDD; except input AR = input MR = 0 V (power-on reset active). AC CHARACTERISTICS VSS = 0 V; Tamb = 25 °C; input transition times 20 ns VDD V Dynamic power dissipation per package (P) Total power dissipation when using the on-chip oscillator (P) Notes 1. where: fi fo CL Ct fosc = input frequency (MHz) = output frequency (MHz) = load capacitance (pF) = timing capacitance (pF) = oscillator frequency (MHz) 5 10 15 5 10 15 1 300 5 300 12 000 fi + fi + fi + 0,4 0,5 1,5 IOL 4,6 9,5 -IOH 13,5 2,5 -IOH VDD - 0,5 1,4 4,8 1,4 0,33 1,00 3,20 - - - - - - - - 8,5 0,4 1,2 4,0 1,2 0,27 0,85 2,70 5 - - - - - - - - - - - - - - - 5 10 15 ID VOL V VOH SYMBOL V - - - -40 MIN. MAX. MIN. 80 750 1600 - - - + 25

HEF4541B MSI

+ 85 80 - 600 - 1300 - - 0,3 0,95 3,2 0,95 0,20 0,68 2,30 230 µA 700 µA 1500 µA - - - - - - - - V mA mA mA mA mA mA mA

TYP. MAX. MIN. MAX. 20 250 500

TYPICAL FORMULA FOR P (µW)(1) foCLVDD2 foCLVDD2 foCLVDD2 foCLVDD2 foCLVDD
2

1 300 fosc + 5 300 fosc + 12 000 fosc +

+ 2CtVDD2 fosc + + 2CtVDD2 fosc 2CtVDD2 fosc

+ 10 VDD + 100 VDD + 400 VDD

foCLVDD2

VDD = supply voltage (V)

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Philips Semiconductors

Product specification

Programmable timer
AC CHARACTERISTICS VSS = 0 V; Tamb = 25 °C; CL = 50 pF; input transition times 20 ns VDD V Propagation delays RS O 28 selected HIGH to LOW LOW to HIGH RS O 210 selected HIGH to LOW LOW to HIGH RS O 213 selected HIGH to LOW LOW to HIGH RS O 216 selected HIGH to LOW LOW to HIGH Minimum clock pulse width; LOW Minimum reset pulse width; HIGH Maximum clock pulse frequency Oscillator frequency 5 10 15 5 10 15 5 10 15 5 10 15 5 10 15 Oscillator frequency 5 10 15 fosc fosc fmax tWMRH tWRSL tPHL; tPLH 60 30 24 60 30 24 8 15 18 575 210 150 30 15 12 30 15 12 16 30 36 90 90 90 8 8 8 1150 ns 420 ns 300 ns ns ns ns ns ns ns MHz MHz MHz kHz kHz kHz kHz kHz kHz Rt = 5 k Ct = 1 nF RS = 10 k Rt = 56 k Ct = 1 nF RS = 120 k 5 10 15 tPHL; tPLH 510 190 135 1020 ns 380 ns 270 ns 5 10 15 tPHL; tPLH 425 165 120 850 ns 330 ns 240 ns 5 10 15 tPHL; tPLH 375 150 110 750 ns 300 ns 220 ns SYMBOL MIN. TYP. MAX.

HEF4541B MSI

TYPICAL EXTRAPOLATION FORMULA

348 ns + (0,55 ns/pF) CL 139 ns + (0,23 ns/pF) CL 102 ns + (0,16 ns/pF) CL 398 ns + (0,55 ns/pF) CL 154 ns + (0,23 ns/pF) CL 112 ns + (0,16 ns/pF) CL 483 ns + (0,55 ns/pF) CL 179 ns + (0,23 ns/pF) CL 127 ns + (0,16 ns/pF) CL 548 ns + (0,55 ns/pF) CL 199 ns + (0,23 ns/pF) CL 142 ns + (0,16 ns/pF) CL

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