Overview
The SN74HC688PW is a digital Comparator made by Texas Instruments in a TSSOP-20 package with 20 pins. -40℃~+85℃ 0.33V 1.8V 2V~6V 36ns@6V,50pF 4.2V 5.2mA 5.2mA 8 8uA A=B Active Low TSSOP-20 Digital Comparators ROHS.
PCBKit's library has its KiCad symbol (74xx:74HC688, from KiCad's library) and its footprint (Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm, from KiCad's library), ready for a KiCad board. 1,743 are in stock at JLCPCB (part C132045).
Symbol
Footprint
From the datasheet
12- Supply, least
- 2 V · VCC, recommended operating min · p. 4
- Supply, most
- 6 V · VCC, recommended operating max · p. 4
- Supply, absolute maximum
- 7 V · VCC, absolute max · p. 4
- Works from
- -40 °C · Operating free-air temperature min · p. 4
- Works up to
- 85 °C · Operating free-air temperature max · p. 4
- Junction, hottest
- 150 °C · Junction temperature absolute max · p. 4
- Takes working
- 80 µA · VCC supply current max, VCC = 6 V, VI = VCC or 0, IO = 0 · p. 5
- A pin gives at most
- 25 mA · Continuous output current absolute max magnitude, VO = 0 to VCC · p. 4
- Junction to air (PW (TSSOP))
- 131.8 K/W · Junction-to-ambient thermal resistance · p. 4
- Junction to case (PW (TSSOP))
- 72.2 K/W · Junction-to-case (top) thermal resistance · p. 4
- Junction to board (PW (TSSOP))
- 82.8 K/W · Junction-to-board thermal resistance · p. 4
- Edge
- 6 ns · Output transition time typical, VCC = 6 V, TA = 25°C, CL = 50 pF · p. 5
What it is and has
4- Comparison
- Two 8-bit words · p. 1
- Output drive
- Up to 10 LSTTL loads · p. 1
- Output drive current
- ±4 mA at 5 V · p. 1
- Package
- TSSOP (20), 6.50 mm × 4.40 mm nominal body · p. 1
Around it
2- cap 0.1-μF
- between VCC and GND; Bypass each VCC terminal; install as close to the power terminal as possible. · p. 8
- cap 1-μF
- between VCC and GND; Commonly used in parallel with the 0.1-uF bypass capacitor to reject different noise frequencies. · p. 8
Specifications
70| Parameter | Conditions | As printed | Page |
|---|---|---|---|
| Supply voltage range VCC | Over operating free-air temperature range | min -0.5 · max 7 V | 4 |
| Input clamp current(2) IIK | VI < 0 or VI > VCC; maximum magnitude, ±20 mA | max 20 mA | 4 |
| Output clamp current(2) IOK | VO < 0 or VO > VCC; maximum magnitude, ±20 mA | max 20 mA | 4 |
| Continuous output current IO | VO = 0 to VCC; maximum magnitude, ±25 mA | max 25 mA | 4 |
| Continuous current through VCC or GND | Maximum magnitude, ±50 mA | max 50 mA | 4 |
| Junction temperature TJ | max 150 ℃ | 4 | |
| Storage temperature range Tstg | min -65 · max 150 ℃ | 4 | |
| Supply voltage VCC | SN74HC688; typ field is NOM | min 2 · typ 5 · max 6 V | 4 |
| High-level input voltage VIH | SN74HC688; VCC = 2 V | min 1.5 V | 4 |
| High-level input voltage VIH | SN74HC688; VCC = 4.5 V | min 3.15 V | 4 |
| High-level input voltage VIH | SN74HC688; VCC = 6 V | min 4.2 V | 4 |
| Low-level input voltage VIL | SN74HC688; VCC = 2 V | max 0.5 V | 4 |
| Low-level input voltage VIL | SN74HC688; VCC = 4.5 V | max 1.35 V | 4 |
| Low-level input voltage VIL | SN74HC688; VCC = 6 V | max 1.8 V | 4 |
| Input voltage VI | SN74HC688; maximum is VCC | min 0 V | 4 |
| Output voltage VO | SN74HC688; maximum is VCC | min 0 V | 4 |
| Input transition (rise and fall) time tt | SN74HC688; VCC = 2 V | max 1000 ns | 4 |
| Input transition (rise and fall) time tt | SN74HC688; VCC = 4.5 V | max 500 ns | 4 |
| Input transition (rise and fall) time tt | SN74HC688; VCC = 6 V | max 400 ns | 4 |
| Operating free-air temperature TA | SN74HC688 | min -40 · max 85 °C | 4 |
| Junction-to-ambient thermal resistance(1) RθJA | PW (TSSOP), 20 PINS | typ 131.8 °C/W | 4 |
| Junction-to-case (top) thermal resistance RθJC(top) | PW (TSSOP), 20 PINS | typ 72.2 °C/W | 4 |
| Junction-to-board thermal resistance RθJB | PW (TSSOP), 20 PINS | typ 82.8 °C/W | 4 |
| Junction-to-top characterization parameter ψJT | PW (TSSOP), 20 PINS | typ 21.5 °C/W | 4 |
| Junction-to-board characterization parameter ψJB | PW (TSSOP), 20 PINS | typ 82.4 °C/W | 4 |
| VOH VOH | SN74HC688; TA = 25°C; VI = VIH or VIL; IOH = –20 uA; VCC = 2 V | min 1.9 · typ 1.998 V | 5 |
| VOH VOH | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOH = –20 uA; VCC = 2 V | min 1.9 V | 5 |
| VOH VOH | SN74HC688; TA = 25°C; VI = VIH or VIL; IOH = –20 uA; VCC = 4.5 V | min 4.4 · typ 4.499 V | 5 |
| VOH VOH | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOH = –20 uA; VCC = 4.5 V | min 4.4 V | 5 |
| VOH VOH | SN74HC688; TA = 25°C; VI = VIH or VIL; IOH = –20 uA; VCC = 6 V | min 5.9 · typ 5.999 V | 5 |
| VOH VOH | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOH = –20 uA; VCC = 6 V | min 5.9 V | 5 |
| VOH VOH | SN74HC688; TA = 25°C; VI = VIH or VIL; IOH = –4 mA; VCC = 4.5 V | min 3.98 · typ 4.3 V | 5 |
| VOH VOH | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOH = –4 mA; VCC = 4.5 V | min 3.84 V | 5 |
| VOH VOH | SN74HC688; TA = 25°C; VI = VIH or VIL; IOH = –5.2 mA; VCC = 6 V | min 5.48 · typ 5.8 V | 5 |
| VOH VOH | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOH = –5.2 mA; VCC = 6 V | min 5.34 V | 5 |
| VOL VOL | SN74HC688; TA = 25°C; VI = VIH or VIL; IOL = 20 uA; VCC = 2 V | typ 0.002 · max 0.1 V | 5 |
| VOL VOL | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOL = 20 uA; VCC = 2 V | max 0.1 V | 5 |
| VOL VOL | SN74HC688; TA = 25°C; VI = VIH or VIL; IOL = 20 uA; VCC = 4.5 V | typ 0.001 · max 0.1 V | 5 |
| VOL VOL | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOL = 20 uA; VCC = 4.5 V | max 0.1 V | 5 |
| VOL VOL | SN74HC688; TA = 25°C; VI = VIH or VIL; IOL = 20 uA; VCC = 6 V | typ 0.001 · max 0.1 V | 5 |
| VOL VOL | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOL = 20 uA; VCC = 6 V | max 0.1 V | 5 |
| VOL VOL | SN74HC688; TA = 25°C; VI = VIH or VIL; IOL = 4 mA; VCC = 4.5 V | typ 0.17 · max 0.26 V | 5 |
| VOL VOL | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOL = 4 mA; VCC = 4.5 V | max 0.33 V | 5 |
| VOL VOL | SN74HC688; TA = 25°C; VI = VIH or VIL; IOL = 5.2 mA; VCC = 6 V | typ 0.15 · max 0.26 V | 5 |
| VOL VOL | SN74HC688; recommended operating free-air temperature range; VI = VIH or VIL; IOL = 5.2 mA; VCC = 6 V | max 0.33 V | 5 |
| II II | SN74HC688; TA = 25°C; VI = VCC or 0; VCC = 6 V; typical and maximum are magnitudes with ± signs | typ 0.1 · max 100 nA | 5 |
| II II | SN74HC688; recommended operating free-air temperature range; VI = VCC or 0; VCC = 6 V; maximum magnitude, ±1000 nA | max 1000 nA | 5 |
| ICC ICC | SN74HC688; TA = 25°C; VI = VCC or 0; IO = 0; VCC = 6 V | max 8 uA | 5 |
| ICC ICC | SN74HC688; recommended operating free-air temperature range; VI = VCC or 0; IO = 0; VCC = 6 V | max 80 uA | 5 |
| Ci Ci | SN74HC688; TA = 25°C; VCC = 2 V to 6 V | typ 3 · max 10 pF | 5 |
| Ci Ci | SN74HC688; recommended operating free-air temperature range; VCC = 2 V to 6 V | max 10 pF | 5 |
| tpd tpd | SN74HC688; TA = 25°C; CL = 50 pF; P or Q to P=Q; VCC = 2 V | typ 113 · max 210 ns | 5 |
| tpd tpd | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; P or Q to P=Q; VCC = 2 V | max 265 ns | 5 |
| tpd tpd | SN74HC688; TA = 25°C; CL = 50 pF; P or Q to P=Q; VCC = 4.5 V | typ 30 · max 42 ns | 5 |
| tpd tpd | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; P or Q to P=Q; VCC = 4.5 V | max 53 ns | 5 |
| tpd tpd | SN74HC688; TA = 25°C; CL = 50 pF; P or Q to P=Q; VCC = 6 V | typ 24 · max 36 ns | 5 |
| tpd tpd | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; P or Q to P=Q; VCC = 6 V | max 45 ns | 5 |
| tpd tpd | SN74HC688; TA = 25°C; CL = 50 pF; OE to P=Q; VCC = 2 V | typ 66 · max 120 ns | 5 |
| tpd tpd | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; OE to P=Q; VCC = 2 V | max 151 ns | 5 |
| tpd tpd | SN74HC688; TA = 25°C; CL = 50 pF; OE to P=Q; VCC = 4.5 V | typ 16 · max 24 ns | 5 |
| tpd tpd | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; OE to P=Q; VCC = 4.5 V | max 30 ns | 5 |
| tpd tpd | SN74HC688; TA = 25°C; CL = 50 pF; OE to P=Q; VCC = 6 V | typ 14 · max 20 ns | 5 |
| tpd tpd | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; OE to P=Q; VCC = 6 V | max 26 ns | 5 |
| tt tt | SN74HC688; TA = 25°C; CL = 50 pF; output Any; VCC = 2 V | typ 38 · max 75 ns | 5 |
| tt tt | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; output Any; VCC = 2 V | max 95 ns | 5 |
| tt tt | SN74HC688; TA = 25°C; CL = 50 pF; output Any; VCC = 4.5 V | typ 8 · max 15 ns | 5 |
| tt tt | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; output Any; VCC = 4.5 V | max 19 ns | 5 |
| tt tt | SN74HC688; TA = 25°C; CL = 50 pF; output Any; VCC = 6 V | typ 6 · max 13 ns | 5 |
| tt tt | SN74HC688; recommended operating free-air temperature range; CL = 50 pF; output Any; VCC = 6 V | max 16 ns | 5 |
| Power dissipation capacitance Cpd | TA = 25℃; No load | typ 40 pF | 5 |
Parameters
20- Current - Output High(IOH)
- 5.2mA
- Current - Output Low(IOL)
- 5.2mA
- Current - Supply
- 80uA
- Input Logic Level - High
- 4.2V
- Input Logic Level - Low
- 1.8V
- Junction Temperature(Max)
- 150℃
- Number of Channels
- 8
- Operating Temperature
- -40℃~+85℃
- Output
- Active Low
- Output Current per Pin(Max)
- 25mA
- Output Function
- A=B
- Output Logic Level - Low
- 0.33V
- Propagation Delay
- 36ns@6V,50pF
- Quiescent Current
- 8uA
- Rise Time
- 6ns
- Thermal Resistance(Junction to Ambient)
- 131.8℃/W
- Thermal Resistance(Junction to Board)
- 82.8℃/W
- Thermal Resistance(Junction to Case)
- 72.2℃/W
- Voltage - Supply
- 2V~6V
- Voltage - Supply(Absolute Max)
- 7V
Order codes
4- SN74HC688PWRLCSC C132045
- SN74HC688PWTLCSC C2653318
- SN74HC688PWRG4LCSC C2653325
- SN74HC688PWTG4LCSC C2653344
Pinout
20| Pin | Name | Type |
|---|---|---|
| 1 | G | Input |
| 2 | P0 | Input |
| 3 | R0 | Input |
| 4 | P1 | Input |
| 5 | R1 | Input |
| 6 | P2 | Input |
| 7 | R2 | Input |
| 8 | P3 | Input |
| 9 | R3 | Input |
| 10 | GND | Power in |
| 11 | P4 | Input |
| 12 | R4 | Input |
| 13 | P5 | Input |
| 14 | R5 | Input |
| 15 | P6 | Input |
| 16 | R6 | Input |
| 17 | P7 | Input |
| 18 | R7 | Input |
| 19 | P=R | Output |
| 20 | VCC | Power in |
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Is there a KiCad symbol and footprint for the SN74HC688PW?
Yes. The symbol is 74xx:74HC688 and the footprint Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm, both drawn on this page. PCBKit places them on a board for you when you design with it.
What package is the SN74HC688PW?
TSSOP-20, with 20 pins. Its footprint is drawn on this page.
Where is the SN74HC688PW datasheet?
Texas Instruments publishes it: the Datasheet link on this page opens it.
Where can I order the SN74HC688PW?
JLCPCB lists it as part C132045, with 1,743 in stock; the sellers' links on this page open their listings.
What can replace the SN74HC688PW?
Parts like it in the library: the CD74HC688PW by Texas Instruments, the 74ACT521MTCX by onsemi and the MM74HC688MTC by onsemi. Check their datasheets: a part that fits the footprint may still differ in its ratings.
Parts like it
3
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TSSOP-20-40℃~+85℃ 10ns@5V,50pF 24mA 24mA 4.5V~5.5V 4uA 8 A=B Active Low Multi-device cascading TSSOP-20 Digital Comparators ROHSonsemiDigital ComparatorsMM74HC688MTC
TSSOP-20-40℃~+85℃ 2V~6V 30ns@6V,50pF 5.2mA 5.2mA 8 8uA A=B Active Low Multi-device cascading、ESD Protection TSSOP-20 Digital Comparators ROHSonsemiDigital Comparators