HEF4541B MSI PROGRAMMABLE TIMER The HEF 45418 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 Ry and C; 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 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 2, 2', 2"? or 2'* depending on the state of the address inputs (Ap, Az). 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 2" frequency divider. |3 |2 fi 12 {13 {10 RS Ctc dire Ag {Aq |MODE cP control inputs S| AR OuTPuT |_O}8 1" BINARY +4 POWER-ON Cp COUNTER STAGE 6;MR RESET Q}PH 7Z83068.2 fra] [3] [2] fit) fro} fs] [a] Vop 41 Ag 1.c.-MODE PH 0 Fig. 1 Functional diagram. HEF4541B HEF4541BP(N): 14-lead DIL; plastic > ERAS (SOT27-1) xs HEF4541BDIF): 14-lead DIL; ceramic (cerdip) Rre Ctc RS nc AR MR Vsg (SOT73) Lt} (2) b3] L4d bs} te} 4 HEF4541BT(D): 14-lead SO; plastic (SOT108-1} Fig. 2 Pinning diagram 7283067-1 (}:; Package Designator North America FAMILY DATA see Family Specifications ipp LIMITS category MSI ( sy 1995 615HEF4541B MSI Pree be RESET cP 28 couNTER 28 p L tL Dr 3 Ltcp 28 COUNTER RESET 22 25 28 ? y ? AR > 0 POWER-ON RESET MR ->o+ PINNING Ag, Ay MODE AR MR PH RTc Ctc RS ee ee ee ee ee ee ce ee MODE [>> cnhotm tc 7 address inputs PH >o>o mode select input auto reset input master reset input phase input external resistor connection (Ry) external capacitor connection (C;) Fig. 3 Logic diagram. external resistor connection (Rg) or external clock input 72830 70.2 616 January ve ) (Programmable timer HEF 4541B MSI FREQUENCY SELECTION TABLE number of t Ag | Az | counter stages | -O5 = an n fout L L 13 8192 LI H 10 1024 HI L 8 256 H|H 16 65 536 FUNCTION TABLE inputs od AR[mR| PH | move | " HL x x auto reset disabled Lit {| x x auto reset enabled ) X 1H x x master reset active X TL Xx H norma operation selected division to output xX fu |x L single-cycle mode?) Xb L x output initially LOW, after reset X IL H x output initially HIGH, after reset H = HIGH state (the more positive voltage) L = LOW state (the less positive voltage) X = state is immaterial 1. For correct power-on reset, the supply voltage should be above 8.5 V. For Vpp < 8.5 V, disable the autoreset and connect AR to Vpp. 2. The timer is initialized on a reset pulse and the output changes state after 2-1 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. \(== 617HEF 45418 MSI RC oscillator reset from logic clock to counter Typical formula for oscillator frequency: 1 fose = === _ 7283069.2 2,3 x Ry x Cy Fig. 4 External component connection for RC oscillator; Rg ~ 2Ry. Timing component limitations The oscillator frequency is mainly determined by RyC;, provided Ry << Rg and RgC2 << RyCy. The function of Rg 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, C, must be larger than the inherent stray capacitance. R, must be larger than the LOCMOS ON resistance in series with it, which typically is 500 Q at Vop = 5 V, 300 Q at Vop = tO V and 200 2 at Vpp = 15 V. The recommended values for these components to maintain agreement with the typical oscillation formula are: C, 2 100 pF, up to any typical value, 10 kQ <A, <1 MN. ~ ==Programmabie timer HEF 4541B MSi 7282715 105 osc (Hz) 104 103 10? 10 104 104 108 aR, (Q) 108 10-4 1073 10-2 Cy(uF) 107! Fig. 5 RC oscillator frequency as a function of Ry and C; at Vpp = 5 to 15 V; Tamb = 28 OC. -- Cy curve at Ry = 56k; Rg = 120 kQ. Ry curve at Cy = 1 nF; Rg = 2R,. \ (~ January 1995 619HEF 4541B MSI 10 7282714 Vv = At DoD (%) NM -10 75 -50 25 0 25 50 75 100 125 150 Tamb (C) Fig. 6 Frequency deviation (Af) as a function of ambient temperature; referenced at : fog at Tamb = 25 C and Vpp = 10 V. Ry = 56 kQ; Cy = TNF; Rg =0. Ry, = 56 kQ; Cy = TF; Rg = 120k. 620 January w=) (Programmabie timer HEF 4541B MSI D.C. CHARACTERISTICS Vsg =OV Tamb (C) Vv Vv Vi V1 et | Sl symbol! 40 +25 +85 min. max. min. typ. max, min. max. Supply current 5 _ 80 20 80 230 vA power-on reset 10 Ip - 750. 250 600 700 pA enabled (note) 15 - 1600 500 1300 1500 pA Supply voltage for automatic reset Voo ~ ~ 85 5 ~ _ - Vv initialization (note) Output current 5 4,6 0,5 ~ 04 - -~ 03 mA HIGH; Crc, Rc} 10 9.5 |-lonw | 14 ~ 1,2 _ ~ 095 - mA 15 13,5 4,8 - 40 ~ ~ 32 - mA 5 2,5 |-lon | 1,4 ~ 1,2 _ ~ 095 - mA Output current 5 0,4 0,33 ~ 0,27 _ ~ 020 - mA LOW; Croc, Rrc | 10 0,5 loL 1,00 ~ 0,85 - ~ 068 - mA 15 1,5 3,20 ~ 270 ~ 230 +- mA Note All inputs at 0 V or Vonp, except input AR = input MR = 0 V (power-on reset active}. A.C. CHARACTERISTICS Vss = 0 V: Tamb = 25 C; input transition times < 20 ns Yep typical formula for P (nW)* Dynamic power dissipation 5 1300 f, + f9CLVpp per package 10 5300 fj + f6CLVpp {P) 15 12.000 f + foCLVop Total power dissipation 5 1300 fose + foCLV pp? + 2CVDD fose + 10 Von when using the 10 5 300 fose t foCL VDD? + 2CrV DD fose + 100 Yop on-chip oscillator (P} 15 12.000 fose + foCL VpD + 2CrV Dp fose + 400 Vpp * where: f; | = input frequency (MHz) fg = output frequency (MHz} C_ = load capacitance (pF) Vop= supply voltage {V) C, = timing capacitance (pF) fosc = oscillator frequency (MHz) \== 621HEF 4541B MSI A.C. CHARACTERISTICS Vss = 0 V; Tamb = 25 C; CL = 50 pF; input transition times < 20 ns Vop typical extrapolation Vv symbol |min. typ. max. formula Propagation delays RS 0 8 i a ene Low 5 |. 375 750 ns__ | 348 ns + (0,55 ns/pF) CL LOW to HIGH 10 onl 150 300 ns) | 139 ns + (0,23 ns/pF) Cy 15 | 'PLH 110 220 ns | 102 ns + (0,16 ns/pF) Cy RS 0 10 2 ane ow 5 | a 425 850 ns | 398 ns + (0,55 ns/pF) Cy LOW to HIGH 10 Put 165 330 ns | 154 ns +(0,23 ns/pF) Cy 15 | PLH 120 240 ns_ | 112 ns + (0,16 ns/pF) Cy. RS O 13 2 ane Low 5 510 1020 ns__| 483 ns + (0,55 ns/pF) CL LOW to HIGH 10 | TPHL: 190 = 380 ns_~| 179.ns + (0,23 ns/pF) Cy 15 | tPLH 135 270 ns | 127 ns + (0,16 ns/pF) Cy RS 0 16 2 nee LOW a 575 1150 ns_ | 548 ns + (0,56 ns/pF) Cr LOW to HIGH 10 ate 210 420 ns__ | 199 ns + (0,23 ns/pF) Cy. 15 |PLH 160 300 ns-_s | 142 ns + (0,16 ns/pF) Cy Minimum clock 5 60 30 ns pulse width; LOW 10 | twrsL_ | 30 15 ns 15 24 12 ns Minimum reset 5 60 30 ns pulse width; HIGH 10 | twmrH | 30 15 ns 15 24 12 ns Maximum clock 5 8 16 MHz pulse frequency 10 | fax 15 30 MHz 15 18 36 MHz Oscillator frequency 5 90 kHz | Ry = 5k2 10 | fose 90 kHz | | Cp = 1nF 15 90 kHz | Rg = 10 k2 Oscillator frequency 5 8 kHz | Ry = 56kQ 10 | fase 8 kHz CG = Inf 15 8 kHz | Rg = 120 kQ 622 January 1995