INTEGRATED CIRCUITS DATA SHEET SAA4945H LIne MEmory noise Reduction IC (LIMERIC) Preliminary specification File under Integrated Circuits, IC02 1997 Jun 10 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H FEATURES GENERAL DESCRIPTION • 2-D adaptive vertically recursive noise reduction The SAA4945H, LIMERIC (LIne MEmory noise Reduction IC) is a 2-D recursive noise reduction filter for both luminance and colour difference signals. The noise reduction is automatically adapted to the global noise level in the image. Ten different preferences of noise reduction can be set using a synchronous receiver transmitter bus; SNERT (Synchronous No parity Eight bit Receive Transmit) bus. Alternatively, the noise reduction can be switched off. The LIMERIC is generally placed directly after the ADC in the feature box and works fully in the 1fh (50/60 Hz) domain. • Noise reduction for Y, U and V signals in 4 : 1 : 1 format • Single 5 V ±10% power supply • Communication by means of serial communication protocol 83C654 (SNERT bus) • Via SNERT bus, 10 different types of noise reduction selectable; the noise reduction function can also be disabled • Phase relation write enable input/output signal simultaneously switchable over one clock period w.r.t. input/output samples • 8-bit wide data processing for Y, U and V; in unsigned format (Y signal) and in 2’s complement (U and V signals) • One fixed line locked clock operation frequency up to 16 MHz (typical) • Exactly one line delay. QUICK REFERENCE DATA SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT VDD supply voltage (pins 5, 29 and 30) 4.5 5.0 5.5 V IDD supply current − 70 − mA − 350 − mW 10 16 17.1 MHz P power dissipation fCLK clock frequency fSNERT bus clock frequency − − 1 MHz Tamb operating ambient temperature 0 − 70 °C ±7%; note 1 Note 1. Maximum number of clocks per line is 1024. ORDERING INFORMATION TYPE NUMBER SAA4945H 1997 Jun 10 PACKAGE NAME DESCRIPTION VERSION QFP44 plastic quad flat package; 44 leads (lead length 1.3 mm); body 10 × 10 × 1.75 mm SOT307-2 2 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H BLOCK DIAGRAM VDD1 handbook, full pagewidth VDD2 VDD3 29 30 5 UI0, UI1 VI0, VI1 16, 15 18, 17 REFORMATTER NOISE REDUCTION FILTER (MULTIPLEXED) 36, 37 ∆t RAM_UV FORMATTER 34, 35 UO0, UO1 VO0, VO1 N_thr_UV NOISE REDUCTION FILTER 8 N_thr_Y 8 38 to 44, 1 RAM_Y N_thr_UV SAA4945H 26 Wval TASTE NTHR NOISE ESTIMATOR TEST CONTROL internal control signals YpScale 14 to 7 YI0 to YI7 SNERT INTERFACE 25 24 31 CONTROL 33 2 SDNA 3 19 21 22 4 CLK Va WEI VRST SNCL Fig.1 Block diagram. 1997 Jun 10 3 6 20 23 27 28 YO0 to YO6, YO7 TST0 TST1 TST2 WEO n.c. 32 GND2 GND4 GND6 GND3 GND5 GND1 MGK170 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H PINNING SYMBOL PIN TYPE DESCRIPTION YO7 1 output luminance output bit 7 SNDA 2 input/output data from interface SNERT bus SNCL 3 input clock from interface SNERT bus VRST 4 input reset in the vertical blanking interval VDD1 5 supply supply voltage 1 GND1 6 ground ground 1 YI7 7 input luminance input bit 7 from analog-to-digital converter YI6 8 input luminance input bit 6 from analog-to-digital converter YI5 9 input luminance input bit 5 from analog-to-digital converter YI4 10 input luminance input bit 4 from analog-to-digital converter YI3 11 input luminance input bit 3 from analog-to-digital converter YI2 12 input luminance input bit 2 from analog-to-digital converter YI1 13 input luminance input bit 1 from analog-to-digital converter YI0 14 input luminance input bit 0 from analog-to-digital converter UI1 15 input U input bit 1 from analog-to-digital converter UI0 16 input U input bit 0 from analog-to-digital converter VI1 17 input V input bit 1 from analog-to-digital converter VI0 18 input V input bit 0 from analog-to-digital converter CLK 19 input master clock GND2 20 ground ground 2 WEI 21 input write enable input Va 22 input vertical blanking pulse GND3 23 ground ground 3 TST2 24 input test pin 2 TST1 25 input test pin 1 TST0 26 input test pin 0 GND4 27 ground ground 4 GND5 28 ground ground 5 VDD2 29 supply supply voltage 2 VDD3 30 supply supply voltage 3 WEO 31 output write enable output GND6 32 ground ground 6 n.c. 33 − not connected VO0 34 output V output bit 0 VO1 35 output V output bit 1 UO0 36 output U output bit 0 UO1 37 output U output bit 1 YO0 38 output luminance output bit 0 YO1 39 output luminance output bit 1 YO2 40 output luminance output bit 2 1997 Jun 10 4 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) TYPE DESCRIPTION YO6 44 output luminance output bit 6 handbook, full pagewidth 36 UO0 luminance output bit 5 37 UO1 luminance output bit 4 output 38 YO0 output 43 39 YO1 42 YO5 40 YO2 YO4 41 YO3 luminance output bit 3 42 YO4 output 43 YO5 41 44 YO6 YO3 34 VO0 PIN 35 VO1 SYMBOL SAA4945H 33 n.c. YO7 1 SNDA 2 32 GND6 SNCL 3 31 WEO VRST 4 30 VDD3 VDD1 5 29 VDD2 GND1 6 28 GND5 SAA4945H Fig.2 Pin configuration. 1997 Jun 10 5 Va 22 WEI 21 GND2 20 CLK 19 23 GND3 VI0 18 24 TST2 VI1 17 YI4 10 YI3 11 UI0 16 25 TST1 YI0 14 26 TST0 YI5 9 UI1 15 YI6 8 YI2 12 27 GND4 YI1 13 YI7 7 MGK169 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H FUNCTIONAL DESCRIPTION LUMINANCE FILTER The digital LIMERIC is an effective low noise reduction IC for luminance and colour difference signals. Noise filtering is automatically adapted to the global noise level which is measured within the picture content. The two dimensional non-linear noise reduction (one for luminance, one for chrominance) uses only line memory to function. Furthermore, up to 10 different preferences can be set by the user. The taps structure of the luminance filter is as shown in Table 2. Table 2 As shown in Fig.1, the main components of the device are the noise reduction filter with the line memories (RAM) and the noise estimator. Other components shown are the reformatter, formatter, controller and a SNERT bus transceiver. Luminance processing X....X...X...X....X ← 5 Y samples from the filtered line (distance 4 / 5 pixel) o.O.o ← 3 Y samples from the incoming line (distance 2 pixels) A ‘weave’ function is used to reduce any smearing effect that could occur at edges. As shown in Tables 3 to 6, the ‘weave’ calculates over 4 consecutive lines. The relative position of the actual pixel changes one position every line. Noise reduction filter Both luminance and chrominance signals are filtered with vertical recursion. This is produced as the filter receives both filtered samples from the previous line, and unfiltered samples from the current line. A new replacement value is calculated for each sample read from the line memory. This in turn, is the filtered response value for the reference input pixel. The reference pixel is then placed at the centre of the delay-line into which the current (unfiltered) video line is shifted. Tables 1 to 6 show this as an ‘O’. Table 3 For line 2n X....X...X...X....X o.O.o Table 4 For line 2n + 1 X....X...X...X....X ..o.O.o Both luminance and colour difference signals are filtered using the so-called Discriminating Averaging Filter (DAF), in which filter coefficients are related to the Absolute Difference (AD) between samples. The filter uses samples from both present and previous line (using the line delay) and the result of the filter is stored back in the line memory. In this way a vertical recursive structure is realized. Table 5 For line 2n + 2 X....X...X...X....X o.O.o Table 6 The filter coefficients are set depending on the noise measured by the noise estimator or the NTHR (SNERT register F9). For line 2n + 3 X....X...X...X....X o.O.o.. Table 7 Weave configuration Depending on even and odd fields the ‘weave’ has the following configuration: CHROMINANCE FILTER The basic signal processing for either U or V is via the same filter. It is used to process both V and U using a multiplexed operation. ODD FIELDS EVEN FIELDS X The taps structure of the chrominance filter is as shown in Table 1. X X X X Table 1 Chrominance processing X X XXXXX ← 5 adjacent R − Y samples from the filtered line X oOo ← 3 adjacent R − Y samples from the incoming line X 1997 Jun 10 X X 6 X X X Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H Noise estimator The threshold value N_thr for the filters is calculated in the noise estimator block (see Fig.3). There are four options for producing the N_thr value: 1. Pre-filter gain setting (YpScale) 2. Wval selects the sensitivity of the noise estimator 3. TASTE (TS) scales the N_thr linear 4. NTHR is externally applied when the noise estimator is disabled by the control bit ExThr of the Status Register. handbook, full pagewidth YI PRE-FILTER NOISE ESTIMATOR × MUX N_thr ExThr MGK171 4 NTHR Wval YpScale TS0-TS3 Fig.3 Noise estimator. SIGNAL DESCRIPTION VI1 AND VI0 (PINS 17 AND 18) Input signals • Colour difference signal V YI7 TO YI0 (PINS 7 TO 14) • Data in 2’s complement; dynamic range between −128 and +127 • Eight bit wide digital luminance input bus • Unsigned data; dynamic range between 0 and 255 • Y : U : V format 4 : 1 : 1; see Table 8 for input data coding • The maximum number of input samples equals 852 active samples/line. • The maximum number of input samples equals 213 samples/line • Internal data processing of V signals in unsigned format. UI1 AND UI0 (PINS 15 AND 16) • Colour difference signal U • Data in 2’s complement; dynamic range between −128 and +127 • Y : U : V format 4 : 1 : 1; see Table 8 for input data coding • The maximum number of input samples equals 213 samples/line • Internal data processing of U signals in unsigned format. 1997 Jun 10 7 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) Table 8 SAA4945H Input /output data coding INPUT Y U V BIT INPUT DATA SEQUENCE Y7 Y07 Y17 Y27 Y37 Y6 Y06 Y16 Y26 Y36 Y5 Y05 Y15 Y25 Y35 Y4 Y04 Y14 Y24 Y34 Y3 Y03 Y13 Y23 Y33 Y2 Y02 Y12 Y22 Y32 Y1 Y01 Y11 Y21 Y31 Y0 Y00 Y10 Y20 Y30 UI1 U07 U05 U 03 U01 UI0 U06 U04 U 02 U00 VI1 V07 V05 V03 V01 VI0 V06 V04 V02 V00 • The number of input samples is a multiple of 4 (see Fig.4) WEI (PIN 21) • Write enable input • Start of new line indicated by write enable signal LOW for at least 4 consecutive clock periods (see Fig.4) • Write enable indicates the time when active input samples (Y, U and V) are present • During active line, WEI is not allowed to be LOW for more than 1 clock cycle. • Timing relation (see Fig.4) depending on the logic level of the Write Enable Select signal (WES) in status register; to adapt to different external video memories 1997 Jun 10 8 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H handbook, full pagewidth CLK WEI line n (WES = 0 status register) WEI (WES = 1 status register) YI0 to YI7 X Y0 Y1 X Y2 X Y3 UI0, UI1 X U0. 7,6 U0. 5,4 X U0. 3,2 X U0. 1,0 VI0, VI1 X V0. 7,6 V0. 5,4 X V0. 3,2 X V0. 1,0 one sequence; X: non valid data CLK WEO line n + 1 (WES = 0 status register) WEO (WES = 1 status register) YI0 to YI7 X Y0 Y1 X Y2 X Y3 UI0, UI1 X U0. 7,6 U0. 5,4 X U0. 3,2 X U0. 1,0 VI0, VI1 X V0. 7,6 V0. 5,4 X V0. 3,2 X V0. 1,0 one sequence; X: non valid data MGK172 Fig.4 Write enable timing. Va (PIN 22) CLK (PIN 19) • Vertical synchronization signal, active HIGH • Line locked system clock, up to 16 MHz typical • Minimum HIGH period equals one line period • All clock related signals act on the rising edge of the system clock. • Vertical synchronization signals converted to system clock domain internally. So the Va pulse can be asynchronous. TST0, TST1 AND TST2 (PINS 26, 25 AND 24) • Test mode inputs • See timing diagram Fig.6 and Table 11 for timing specification. 1997 Jun 10 • Active HIGH, with internal pull-down resistors. 9 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) Table 9 SAA4945H Test settings TST2 0 TST1 TST0 MODE 0 0 application mode X(1) 1 X(1) test mode 1 X(1) X(1) test mode X(1) X(1) 1 test mode Note 1. X = don’t care. SNDA, SNCL AND VRST (PINS 2, 3 AND 4) • Serial interface signals • SNERT bus protocol (Synchronous No parity 8-bit receiver and Transmission bus) • SNDA is a bidirectional signal with 8-bit wide data and address (LSB first) • Serial interface signals converted (internally) to system clock domain. To avoid set-up violations these signals are clocked two times by the system clock before further processing is performed. • Synchronization of serial address (every even byte) and data (every odd byte) by VRST. Tcy(SNCL) handbook, full pagewidth SNCL tsu(i)(D) SNDA (receiver mode) th(D) LSB th(Q) SNDA (transmitter mode) data valid data valid data valid data valid data valid data valid data valid MGK173 td(D) Fig.5 Timing diagram of serial interface. Table 10 Timing characteristics (see Fig.5) SYMBOL PARAMETER MIN. MAX. UNIT tcy(SNCL) SNCL cycle time 1 − µs tsu(i)(D) input set-up time 90 − ns th(D) input hold time 50 − ns th(Q) output data hold time 0 − ns td(D) output data delay time − 700 ns 1997 Jun 10 10 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H Output signals WEO (PIN 31) YO0 TO YO7 (PINS 38 TO 44 AND 1) • Write enable output • 8-bit wide digital luminance output bus • Write enable indicates the time when active samples (Y, U and V) are present • Data format: unsigned, dynamic range between 0 and 255. • Timing relation (see Fig.6) depending on write enable select signal (WES) in status register; to adapt to different external video memories UO1 AND UO0 (PINS 37 AND 36) • The number of output samples is a multiple of 4 • Colour difference signal U • The write enable output sequence is a copy of the write enable input sequence of the previous line (see Fig.6) with a shift of one line • Data format: 2’s complement, dynamic range between −128 and +127 • Y : U : V format 4 : 1 : 1; see Table 8. • The last line in field is not processed. VO1 AND VO0 (PINS 35 AND 34) • Colour difference signal V • Data format: 2’s complement, dynamic range between −128 and +127 • Y : U : V format 4 : 1 : 1; see Table 8. t(Va-WE)LH tVa(min)H handbook, full pagewidth Va t(Va-VRST)LH tsu(Va) VRST t(WE-VRST)LH WEI L(n−1) L(n) WEO L(n−2) L(n−1) L(0) L(1) L(2) L(0) L(1) 1 clk cycle internal flag to mask WEO MGK174 Fig.6 Timing diagram for WEO blanking and Va. 1997 Jun 10 11 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H Table 11 Va versus VRST SYMBOL PARAMETER MIN. UNIT tVa(min)H minimum Va HIGH time 64 µs tsu(Va) set-up Va to negative edge of WEI 0 µs t(Va-WE)LH Va LOW to WEI HIGH time 0 µs t(Va-VRST)LH Va LOW to VRST HIGH time 0 µs t(WE-VRST)LH WEI LOW to VRST HIGH time 64 µs LIST OF SNERT BUS ADDRESSES USED IN LIMERIC TASTE register Table 12 TASTE register usage USE ACTION Purpose to set 4 different types of noise reduction Address F3 Read/write write Range 0 to 4; 0 = noise filtering disabled Table 13 TASTE register content MSB 0 LSB 0 0 0 ts3 ts2 ts1 ts0 REMARK see Table 14 Table 14 TASTE setting TS3 TS2 TS1 TS0 0 0 0 0 noise filtering disabled 0 0 0 1 not applicable 0 0 1 0 noise reduction; TASTE 1 0 0 1 1 not applicable 0 1 0 0 noise reduction; TASTE 2 0 1 0 1 not applicable 0 1 1 0 noise reduction; TASTE 3 0 1 1 1 not applicable 1 0 0 0 noise reduction; TASTE 4 1 0 0 1 not applicable 1 0 1 0 not applicable 1 0 1 1 not defined 1 1 0 0 not defined 1 1 0 1 not defined 1 1 1 0 not defined 1 1 1 1 not defined 1997 Jun 10 FUNCTION 12 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H Status register Table 15 Status register usage USE ACTION Purpose internal settings Address F4 Read/write write Table 16 Status register content MSB Tctrl3 LSB Tctrl2 Tctrl1 X ExThr Wv DEM WES Table 17 Status register description BIT 0 NAME WES DESCRIPTION Write Enable Select 0: data coincides with write enable (both input and output) 1: data is delayed over one clock period with respect to the write enable (both input and output) see Fig.4 1 DEM Demo Mode 0: demo mode disabled 1: demo mode on; the noise reduction circuit is switched on for the left half of the screen - the noise reduction is disabled (split screen function) for the right half of the screen 2 Wv Weave 0: enable weave 1: disable weave 3 ExThr External Threshold control bit 0: N_thr calculated by noise estimator 1: value of N_thr from register F9 is used 4 X don’t care 5 Tctrl1 Test control 1 0: normal operation 1: test mode 6 Tctrl2 Test control 2 0: normal operation 1: test mode 5 Tctrl3 Test control 3 0: normal operation 1: test mode 1997 Jun 10 13 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H Wval register (wanted value) Table 18 Wval register usage USE ACTION Purpose register for setting up noise estimator Address F5 Read/write write Range 0 to 255 Table 19 Wval register MSB LSB Wval6 Wval7 Wval5 Wval4 Wval3 Wval2 Wval1 Wval0 CONDITIONS Tctrl2 = 0 Noise threshold register Table 20 Noise threshold register usage USE ACTION Purpose register for setting the NTHR value for the noise filter externally Address F9 Read/write write Range 0 to 255 Table 21 Noise threshold register content MSB NTHR[7] LSB NTHR[6] NTHR[5] NTHR[4] NTHR[3] NTHR[2] NTHR[1] NTHR[0] Noise estimator setting register Table 22 Noise estimator setting register usage USE ACTION Purpose register for general setting of the noise estimator Address FA Read/write write Table 23 Noise estimator setting register MSB YpScale1 LSB YpScale0 0 0 0 0 Table 24 Noise estimator setting description YpScale1 YpScale0 0 0 noise estimator pre-filter gain setting = 1 0 1 noise estimator pre-filter gain setting = 0.5 1 0 noise estimator pre-filter gain setting = 0.25 1 1 noise estimator pre-filter bypassed 1997 Jun 10 DESCRIPTION 14 0 0 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H LIMITING VALUES In accordance with the Absolute Maximum Rating System (IEC 134). SYMBOL PARAMETER MIN. MAX. UNIT VDD1 supply voltage 1 −0.5 +6.5 V VDD2 supply voltage 2 −0.5 +6.5 V VI input voltage −0.5 +6.5 V Tstg storage temperature −55 +150 °C Tamb operating ambient temperature −40 +85 °C Ptot total power dissipation − 150 mW PO(pin) output power dissipation per output pin − 100 mW THERMAL CHARACTERISTICS SYMBOL Rth(j-a) 1997 Jun 10 PARAMETER CONDITIONS thermal resistance from junction to ambient 15 in free air VALUE UNIT 65 K/W Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H CHARACTERISTICS VDD = 5 V; Tamb = 25 °C; unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT Supply VDD supply voltage (pins 5, 29 and 30) 4.5 5.0 5.5 V IDD supply current − 70 − mA Tamb operating ambient temperature 0 − 70 °C Tstg storage temperature −50 − +150 °C P power dissipation − 350 − mW CLK ±7%; note 1 fCLK clock frequency 10 16 17.1 MHz δ duty cycle 40 − 60 % VIL LOW-level input voltage − − 0.8 V VIH HIGH-level input voltage 2 − − V CL load capacitance 10 − − pF − − 0.8 V YI7 to YI0, UI1, UI2, VI1, VI0, WEI and Va VIL LOW-level input voltage 2.0 − − V − − ±20 µA set-up time 6 − − ns hold time 7 − − ns VIH HIGH-level input voltage II input current tsu(i)(D) th(D) VI = 0 to 5 V YO7 to YO0, UO1, UO2, VO1, VO0 and WEO VOL LOW-level output voltage IOL = 1.6 mA − − 0.4 V VOH HIGH-level output voltage IOH = 0.4 mA 2.4 − − V th(Q) output hold CL = 15 pF 7 − − ns td(D) output delay CL = 15 pF − − 32 ns SNDA and SNCL fSNERT bus clock frequency − − 1 MHz VIL LOW-level input voltage − − 0.8 V VIH HIGH-level input voltage 2.0 − − V VOL LOW-level output voltage − − 0.4 V VOH HIGH-level output voltage 2.4 − − V TST0, TST1 and TST2 VIL LOW-level input voltage − − 0.8 V VIH HIGH-level input voltage 2.0 − − V Note 1. Maximum number of clocks per line is 1024. 1997 Jun 10 16 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H PACKAGE OUTLINE QFP44: plastic quad flat package; 44 leads (lead length 1.3 mm); body 10 x 10 x 1.75 mm SOT307-2 c y X A 33 23 34 22 ZE e Q E HE A A2 wM (A 3) A1 θ bp Lp pin 1 index L 12 44 1 detail X 11 wM bp e ZD v M A D B HD v M B 0 2.5 5 mm scale DIMENSIONS (mm are the original dimensions) UNIT A max. A1 A2 A3 bp c D (1) E (1) e HD HE L Lp Q v w y mm 2.10 0.25 0.05 1.85 1.65 0.25 0.40 0.20 0.25 0.14 10.1 9.9 10.1 9.9 0.8 12.9 12.3 12.9 12.3 1.3 0.95 0.55 0.85 0.75 0.15 0.15 0.1 Z D (1) Z E (1) 1.2 0.8 1.2 0.8 θ Note 1. Plastic or metal protrusions of 0.25 mm maximum per side are not included. OUTLINE VERSION REFERENCES IEC JEDEC EIAJ ISSUE DATE 92-11-17 95-02-04 SOT307-2 1997 Jun 10 EUROPEAN PROJECTION 17 o 10 0o Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H SOLDERING Wave soldering Introduction Wave soldering is not recommended for QFP packages. This is because of the likelihood of solder bridging due to closely-spaced leads and the possibility of incomplete solder penetration in multi-lead devices. There is no soldering method that is ideal for all IC packages. Wave soldering is often preferred when through-hole and surface mounted components are mixed on one printed-circuit board. However, wave soldering is not always suitable for surface mounted ICs, or for printed-circuits with high population densities. In these situations reflow soldering is often used. If wave soldering cannot be avoided, the following conditions must be observed: • A double-wave (a turbulent wave with high upward pressure followed by a smooth laminar wave) soldering technique should be used. This text gives a very brief insight to a complex technology. A more in-depth account of soldering ICs can be found in our “IC Package Databook” (order code 9398 652 90011). • The footprint must be at an angle of 45° to the board direction and must incorporate solder thieves downstream and at the side corners. Reflow soldering Even with these conditions, do not consider wave soldering the following packages: QFP52 (SOT379-1), QFP100 (SOT317-1), QFP100 (SOT317-2), QFP100 (SOT382-1) or QFP160 (SOT322-1). Reflow soldering techniques are suitable for all QFP packages. The choice of heating method may be influenced by larger plastic QFP packages (44 leads, or more). If infrared or vapour phase heating is used and the large packages are not absolutely dry (less than 0.1% moisture content by weight), vaporization of the small amount of moisture in them can cause cracking of the plastic body. For more information, refer to the Drypack chapter in our “Quality Reference Handbook” (order code 9398 510 63011). During placement and before soldering, the package must be fixed with a droplet of adhesive. The adhesive can be applied by screen printing, pin transfer or syringe dispensing. The package can be soldered after the adhesive is cured. Maximum permissible solder temperature is 260 °C, and maximum duration of package immersion in solder is 10 seconds, if cooled to less than 150 °C within 6 seconds. Typical dwell time is 4 seconds at 250 °C. Reflow soldering requires solder paste (a suspension of fine solder particles, flux and binding agent) to be applied to the printed-circuit board by screen printing, stencilling or pressure-syringe dispensing before package placement. A mildly-activated flux will eliminate the need for removal of corrosive residues in most applications. Several techniques exist for reflowing; for example, thermal conduction by heated belt. Dwell times vary between 50 and 300 seconds depending on heating method. Typical reflow temperatures range from 215 to 250 °C. Repairing soldered joints Fix the component by first soldering two diagonallyopposite end leads. Use only a low voltage soldering iron (less than 24 V) applied to the flat part of the lead. Contact time must be limited to 10 seconds at up to 300 °C. When using a dedicated tool, all other leads can be soldered in one operation within 2 to 5 seconds between 270 and 320 °C. Preheating is necessary to dry the paste and evaporate the binding agent. Preheating duration: 45 minutes at 45 °C. 1997 Jun 10 18 Philips Semiconductors Preliminary specification LIne MEmory noise Reduction IC (LIMERIC) SAA4945H DEFINITIONS Data sheet status Objective specification This data sheet contains target or goal specifications for product development. Preliminary specification This data sheet contains preliminary data; supplementary data may be published later. Product specification This data sheet contains final product specifications. Limiting values Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability. Application information Where application information is given, it is advisory and does not form part of the specification. LIFE SUPPORT APPLICATIONS These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Philips customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such improper use or sale. 1997 Jun 10 19 Philips Semiconductors – a worldwide company Argentina: see South America Australia: 34 Waterloo Road, NORTH RYDE, NSW 2113, Tel. +61 2 9805 4455, Fax. +61 2 9805 4466 Austria: Computerstr. 6, A-1101 WIEN, P.O. Box 213, Tel. +43 1 60 101, Fax. +43 1 60 101 1210 Belarus: Hotel Minsk Business Center, Bld. 3, r. 1211, Volodarski Str. 6, 220050 MINSK, Tel. +375 172 200 733, Fax. +375 172 200 773 Belgium: see The Netherlands Brazil: see South America Bulgaria: Philips Bulgaria Ltd., Energoproject, 15th floor, 51 James Bourchier Blvd., 1407 SOFIA, Tel. +359 2 689 211, Fax. +359 2 689 102 Canada: PHILIPS SEMICONDUCTORS/COMPONENTS, Tel. +1 800 234 7381 China/Hong Kong: 501 Hong Kong Industrial Technology Centre, 72 Tat Chee Avenue, Kowloon Tong, HONG KONG, Tel. +852 2319 7888, Fax. +852 2319 7700 Colombia: see South America Czech Republic: see Austria Denmark: Prags Boulevard 80, PB 1919, DK-2300 COPENHAGEN S, Tel. +45 32 88 2636, Fax. +45 31 57 0044 Finland: Sinikalliontie 3, FIN-02630 ESPOO, Tel. +358 9 615800, Fax. +358 9 61580920 France: 4 Rue du Port-aux-Vins, BP317, 92156 SURESNES Cedex, Tel. +33 1 40 99 6161, Fax. +33 1 40 99 6427 Germany: Hammerbrookstraße 69, D-20097 HAMBURG, Tel. +49 40 23 53 60, Fax. +49 40 23 536 300 Greece: No. 15, 25th March Street, GR 17778 TAVROS/ATHENS, Tel. +30 1 4894 339/239, Fax. +30 1 4814 240 Hungary: see Austria India: Philips INDIA Ltd, Shivsagar Estate, A Block, Dr. Annie Besant Rd. Worli, MUMBAI 400 018, Tel. +91 22 4938 541, Fax. +91 22 4938 722 Indonesia: see Singapore Ireland: Newstead, Clonskeagh, DUBLIN 14, Tel. +353 1 7640 000, Fax. +353 1 7640 200 Israel: RAPAC Electronics, 7 Kehilat Saloniki St, PO Box 18053, TEL AVIV 61180, Tel. +972 3 645 0444, Fax. +972 3 649 1007 Italy: PHILIPS SEMICONDUCTORS, Piazza IV Novembre 3, 20124 MILANO, Tel. +39 2 6752 2531, Fax. +39 2 6752 2557 Japan: Philips Bldg 13-37, Kohnan 2-chome, Minato-ku, TOKYO 108, Tel. +81 3 3740 5130, Fax. +81 3 3740 5077 Korea: Philips House, 260-199 Itaewon-dong, Yongsan-ku, SEOUL, Tel. +82 2 709 1412, Fax. +82 2 709 1415 Malaysia: No. 76 Jalan Universiti, 46200 PETALING JAYA, SELANGOR, Tel. +60 3 750 5214, Fax. +60 3 757 4880 Mexico: 5900 Gateway East, Suite 200, EL PASO, TEXAS 79905, Tel. +9-5 800 234 7381 Middle East: see Italy Netherlands: Postbus 90050, 5600 PB EINDHOVEN, Bldg. VB, Tel. +31 40 27 82785, Fax. +31 40 27 88399 New Zealand: 2 Wagener Place, C.P.O. Box 1041, AUCKLAND, Tel. +64 9 849 4160, Fax. +64 9 849 7811 Norway: Box 1, Manglerud 0612, OSLO, Tel. +47 22 74 8000, Fax. +47 22 74 8341 Philippines: Philips Semiconductors Philippines Inc., 106 Valero St. Salcedo Village, P.O. Box 2108 MCC, MAKATI, Metro MANILA, Tel. +63 2 816 6380, Fax. +63 2 817 3474 Poland: Ul. Lukiska 10, PL 04-123 WARSZAWA, Tel. +48 22 612 2831, Fax. +48 22 612 2327 Portugal: see Spain Romania: see Italy Russia: Philips Russia, Ul. Usatcheva 35A, 119048 MOSCOW, Tel. +7 095 755 6918, Fax. +7 095 755 6919 Singapore: Lorong 1, Toa Payoh, SINGAPORE 1231, Tel. +65 350 2538, Fax. +65 251 6500 Slovakia: see Austria Slovenia: see Italy South Africa: S.A. PHILIPS Pty Ltd., 195-215 Main Road Martindale, 2092 JOHANNESBURG, P.O. Box 7430 Johannesburg 2000, Tel. +27 11 470 5911, Fax. +27 11 470 5494 South America: Rua do Rocio 220, 5th floor, Suite 51, 04552-903 São Paulo, SÃO PAULO - SP, Brazil, Tel. +55 11 821 2333, Fax. +55 11 829 1849 Spain: Balmes 22, 08007 BARCELONA, Tel. +34 3 301 6312, Fax. +34 3 301 4107 Sweden: Kottbygatan 7, Akalla, S-16485 STOCKHOLM, Tel. +46 8 632 2000, Fax. +46 8 632 2745 Switzerland: Allmendstrasse 140, CH-8027 ZÜRICH, Tel. +41 1 488 2686, Fax. +41 1 481 7730 Taiwan: Philips Semiconductors, 6F, No. 96, Chien Kuo N. Rd., Sec. 1, TAIPEI, Taiwan Tel. +886 2 2134 2865, Fax. +886 2 2134 2874 Thailand: PHILIPS ELECTRONICS (THAILAND) Ltd., 209/2 Sanpavuth-Bangna Road Prakanong, BANGKOK 10260, Tel. +66 2 745 4090, Fax. +66 2 398 0793 Turkey: Talatpasa Cad. No. 5, 80640 GÜLTEPE/ISTANBUL, Tel. +90 212 279 2770, Fax. +90 212 282 6707 Ukraine: PHILIPS UKRAINE, 4 Patrice Lumumba str., Building B, Floor 7, 252042 KIEV, Tel. +380 44 264 2776, Fax. +380 44 268 0461 United Kingdom: Philips Semiconductors Ltd., 276 Bath Road, Hayes, MIDDLESEX UB3 5BX, Tel. +44 181 730 5000, Fax. +44 181 754 8421 United States: 811 East Arques Avenue, SUNNYVALE, CA 94088-3409, Tel. +1 800 234 7381 Uruguay: see South America Vietnam: see Singapore Yugoslavia: PHILIPS, Trg N. Pasica 5/v, 11000 BEOGRAD, Tel. +381 11 625 344, Fax.+381 11 635 777 For all other countries apply to: Philips Semiconductors, Marketing & Sales Communications, Building BE-p, P.O. Box 218, 5600 MD EINDHOVEN, The Netherlands, Fax. +31 40 27 24825 Internet: http://www.semiconductors.philips.com © Philips Electronics N.V. 1997 SCA54 All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent- or other industrial or intellectual property rights. Printed in The Netherlands 547047/20/01/pp20 Date of release: 1997 Jun 10 Document order number: 9397 750 01608